Enzyme-containing granules for manufacturing animal feed compositions are prepared using a carrier containing at least about 15% (w/w) carbohydrate such as starch and less than 5% (w/w) protein. A mixture is formed containing an enzyme, the carrier and water, with or without prior kneading to improve plasticity, the mixture is mechanically processed such as by extrusion with a basket or dome extruder while not allowing the temperature of the mixture to rise above about 40xc2x0 C., and drying the resultant enzyme-containing granules. The granules may be spheronised prior to drying, and drying may be in a fluid bed agglomerator. The water and enzyme may be provided as an enzyme-containing aqueous liquid such as an enzyme-containing filtrate from a fermentation process. Enzymes include phytase, endo-xylanase and xcex2-glucanase. Other components that may be in the granules include divalent cations, cellulose, polyvinyl alcohol and an edible oil. Animal feed compositions may be prepared by mixing the granules with feed ingredients, sterilizing or treating with steam, and pelleting. The compositions show improved enzyme stability during pelleting.

The present invention relates to the formulation of enzymes, preferably feed-enzymes, into carbohydrate (e.g., starch-) containing granulates, and to processes for the preparation of such enzyme-containing granulates. These (edible) granulates can then be used in animal feeds.
The use of various enzymes in animal, e.g., livestock, feed has become almost common practice. These enzymes are usually produced by culturing microorganisms in large. scale fermenters operated by industrial enzyme producers. At the end of the fermentation the resulting xe2x80x9cbrothxe2x80x9d is usually subjected to a series of filtration steps to separate the biomass (the microorganisms) from the desired enzyme (in solution). The enzyme solution is either then sold as a liquid (often after addition of various stabilizers) or processed to a dry formulation.
Enzyme liquid and dry formulations are used on a commercial scale by the feed industry. Liquid formulations may be added to the feed after pelleting in order to avoid heat inactivation of the enzyme(s) which would occur during the pelleting process. However the amounts of enzyme in the final feed preparations are usually very small which makes it difficult to achieve a homogenous distribution of the enzyme in the feed, and liquids are notoriously more difficult to mix evenly than dry ingredients. In addition one needs specialised (expensive) equipment to add liquids to the feed after pelleting which is not currently available at most feed mills (due to the extra cost).
Dry formulations of enzyme(s), on the other hand, have the disadvantage of heat-inactivation of the enzymes during pelleting. Preferred manufacturing protocols in the feed industry involve steam pelleting where the feed is subjected to steam injection(s) prior to pelleting. In the subsequent pelleting step the feed is forced through a matrix or die and the resulting strips are cut into suitable pellets of variable length. The moisture content immediately before pelleting is generally between 18% and 19%. During this process temperatures may rise to 60-95xc2x0 C. The combined effect of high moisture content and high temperature is detrimental to most enzymes. These disadvantages are also encountered in other types of thermomechanical treatments such as extrusion and expansion.
In order to try and overcome these problems EP-A-0,257,996 (Cultor Ltd.) suggests that the stability of enzymes in feed processing could be increased by the preparation of an enzyme xe2x80x9cpremixxe2x80x9d where an enzyme-containing solution is absorbed onto a grain-based carrier consisting of flour, and the premix is subsequently pelleted and dried. However, these flour-based premixes are not suitable for gentler methods of processing (of the dough-like premix) into granulates, such as low-pressure extrusion or high shear granulation, because of the gluey character of the flour-based premixes.
Various enzyme manufacturers have developed alternative formulation methods to try to improve the stability of dry enzyme products during pelleting and storage.
EP-A-0,569,468 (Novo Nordisk) refers to a formulation consisting of a enzyme-containing xe2x80x9cT-granulatexe2x80x9d that is coated with a high melting wax or fat alleged to improve resistance to pelleting conditions. The granulate is prepared by mixing a dry inorganic (e.g., sodium sulphate) filler with the enzyme solution in a high shear granulator. EP-A-0,569,468 teaches that any beneficial effect of the coating with respect to pelleting stability is specific for the type of granulate coated, which in this case is based on a sodium sulphate filler. However, the absorption capacity of these (sodium sulphate) fillers is much less than that of carriers such as flour, which is undesirable if one wishes to produce more concentrated enzyme-containing granulates.
In addition, the granulates have a wide particle size distribution which makes it difficult to obtain a homogeneous enzyme concentration throughout. Moreover the bioavailability of the enzyme to the animal is decreased by the wax or fat coating.
WO-A-97/16076 (Novo Nordisk) also refers to the use of waxes and other water-insoluble substances in particulates, but here they are employed as a matrix material.
There is thus a need for stable formulations of enzymes that are based on a carrier that is suitable for granulation methods other than pelleting and that can have a high absorption capacity. Further objects and advantages of the invention will be apparent from the description herein.
The present invention provides carbohydrate-based enzyme granulates and methods for the preparation of same. The granulates can be employed inter alia in animal feed compositions.
In a first preferred aspect of the present invention there is provided a process for the preparation of an enzyme-containing granulate suitable for use in an animal feed, the process preferably comprising processing an enzyme, a solid carrier comprising at least about 15% (w/w) of an edible carbohydrate polymer, and water in appropriate relative amounts to obtain enzyme-containing granules, and subsequently drying the granules. The enzyme-containing granulate produceable by this process (which forms the second preferred aspect of the invention that preferably covers a granulate comprising dried granules formed from an enzyme and a solid carrier which comprises at least about 15% (w/w) of an edible carbohydrate polymer) seeks to solve or at least mitigates the problems encountered in the prior art.
The invention can thus preferably provide processes for the preparation of enzyme formulations in the form of granulates that use the carbohydrate as a carrier. The carrier desirably can be in particulate or powder form. The enzyme and water are preferably provided as an enzyme-containing (preferably aqueous) liquid, such as a solution or a slurry, which can be mixed with the solid carrier and allowed to absorb onto the carrier. During or after the mixing, the enzyme-containing liquid and the carrier are processed into a granulate, which optionally can then subsequently be dried. The use of the carbohydrate carrier can allow the absorption of large amounts of enzyme-containing liquid (and therefore enzyme). The mixture desirably can be used to form a plastic paste or non-elastic dough that can readily be processed into granules, for example it is extrudable. Suitably the carrier is non-fibrous which allows for easier granulation: fibrous materials can prevent granulation by extrusion.
A number of prior art documents refer to pellets containing various enzymes, but these find use as detergents, often in washing compositions. In contrast, the present invention finds use in animal feeds and, for that reason, the granulates of the invention are edible (by animals) and preferably also digestible. It therefore is a surprising and unexpected aspect of the present invention that the granulates, granules and compositions of the invention are free of soap, detergents and bleach or bleaching compounds, zeolites, binders, fillers (TiO2, kaolin, silicates, talc, etc.) to name but a few.
The edible carbohydrate polymer should be chosen so that it is edible by the animal for whom the feed is intended, and preferably is digestible as well. The polymer preferably comprises glucose (e.g., a glucose-containing polymer), or (C6H105)n, units. Preferably the carbohydrate polymer comprises xcex1-D-glucopyranose units, amylose (a linear (1xe2x86x924) xcex1-D-glucan polymer) and/or amylopectin (a branched D-glucan with xcex1-D-(1xe2x86x924) and xcex1-D-(1xe2x86x926) linkages). Starch is the preferred carbohydrate polymer. Other suitable glucose-containing polymers that can be used instead of, or in addition to starch, include xcex1-glucans, xcex2-glucans, pectin (such as proto-pectin), and glycogen. Derivatives of these carbohydrate polymers, such as ethers and/or esters thereof, are also contemplated although gelatinised starch is best avoided and thus may not be present. Suitably the carbohydrate polymer is water-insoluble.
In the examples described herein corn-, potato- and rice-starch is used. However, starch obtained from other (e.g., plant, such as vegetable or crop) sources such as tapioca, cassava, wheat, maize, sago, rye, oat, barley, yam, sorghum, or arrowroot is equally applicable. Similarly both native or modified (e.g., dextrin) types of starch can be used in the invention. Preferably the carbohydrate (e.g., starch) contains little or no protein, e.g., less than about 5% (w/w), such as less than about 2% (w/w), preferably less than about 1% (w/w). Even more desirably, the carbohydrate contains from about 0.005% (w/w) to about 1% (w/w). Regardless of the type of starch (or other carbohydrate polymer) it should be in a form that allows it to be used in an animal feed, in other words an edible or digestible form.
At least about 15% (w/w) of the solid carrier desirably can comprise the carbohydrate polymer (such as starch). Preferably, however, at least about 30% (w/w) of the solid carrier comprises the carbohydrate, optimally at least about 40% (w/w). Advantageously the major component of the solid carrier is the carbohydrate (e.g., starch), for example more than about 50% (w/w), preferably at least about 60% (w/w), suitably.: at least about 70% (w/w), and optimally at least about 80% (w/w). Thus, desirably the carbohydrate comprises from about 40% to about 100% (w/w), particularly from about 70% to about 90% (w/w) of the solid carrier. These weight percentages are based on the total weight of the non-enzymatic components in the final dry granulate.
In the process of the invention the enzyme and water can be present in the same composition before contacting the solid carrier. In this respect, one preferably can provide an enzyme-containing aqueous liquid. This liquid preferably can be a solution or a slurry that is from, or derived from, a fermentation process. This fermentation process will usually be one in which the enzyme is produced. The fermentation process desirably can result in a broth which contains the microorganisms (which produce the desired enzyme) and an aqueous solution. This aqueous solution, once separated from the microorganisms (for example, by filtration) desirably can be the enzyme-containing aqueous liquid used in the invention. Thus, in preferred embodiments the enzyme-containing aqueous liquid is a filtrate.
The amount of enzyme-containing liquid (and so enzyme) that can be absorbed onto the carrier is usually limited by the amount of water that can be absorbed. For natural, granular, starch this can vary between from about 25% (w/w) to about 30% (w/w), without using elevated temperatures (that cause the starch to swell). In practice the percentage of enzyme liquid to be added to the carbohydrate will often be much larger than this because the enzyme containing liquid will usually contain a significant amount of solids. The enzyme solution can contain about 25% (w/w) solids (optimally from about 15% to about 40% (w/w)), as a result of which the carbohydrate (e.g., starch) and enzyme solution can be mixed at a ratio of carbohydrate:enzyme solution of from about 0.5:1 to about 2:1, e.g., from about 1.2:1 to about 1.6:1, such as at a ratio of about 60% (w/w):40% (w/w), respectively. Preferably the amount of liquid added to the solid carrier is such that (substantially) all the water in the (aqueous) liquid is absorbed by the carbohydrate present in the solid carrier.
At elevated temperatures starch and other carbohydrate polymers can absorb much larger amounts of water under swelling. For this reason the carbohydrate polymer is desirably able to absorb water (or enzyme-containing aqueous liquids). For example, corn starch can absorb up to three times its weight of water at 60xc2x0 C. and up to ten times at 70xc2x0 C. The use of higher temperatures in order to absorb a greater amount enzyme-containing liquid is thus contemplated by the present invention, and indeed is preferable especially when dealing with thermostable enzymes. For these enzymes therefore the mixing of the solid carrier and liquid (or enzyme and water) can be conducted at elevated temperatures (e.g., above ambient temperature), such as above about 30xc2x0 C., preferably above about 40xc2x0 C., and optimally above about 50xc2x0 C. In particular, depending on the thermostability of the enzymes employed, desirably mixing can be done at temperatures from about 30xc2x0 C. to about 80xc2x0 C. Alternatively or in addition, the liquid can be provided at this temperature.
However, in general, non-swelling conditions at lower (e.g., ambient) temperatures are preferred. This can minimise activity loss arising from instability of (heat sensitive) enzymes at higher temperatures. Suitably the temperature during the mixing of the enzyme and water is from about 20xc2x0 C. to about 35xc2x0 C., and more preferably at from about 20xc2x0 C. to about 25xc2x0 C.
The mechanical processing used in the present invention for making the mixture of the enzyme, water (e.g., an enzyme-containing liquid) and the solid carrier into granules (in other words granulating) can employ known techniques frequently used in food, feed and enzyme formulation processes. This can comprise expansion, extrusion, spheronisation, pelleting, high shear granulation, drum granulation, fluid bed agglomeration or a combination thereof. These processes are usually characterised by an input of mechanical energy, such as the drive of a screw, the rotation of a mixing mechanism, the pressure of a rolling mechanism of a pelleting apparatus, the movement of particles by a rotating bottom plate of a fluid bed agglomerator or the movement of the particles by a gas stream, or a combination thereof. These processes allow the solid carrier (e.g., in the form of a powder), to be mixed with the enzyme and water, for example an enzyme-containing liquid (an aqueous solution or slurry), and so subsequently granulated.
Alternatively the solid carrier desirably can be mixed with the enzyme (e.g., in a powder form) to which water, such as a liquid (or slurry) is then added (which can act as granulating liquid).
In yet a further preferred embodiment of the invention the granulate (e.g., an agglomerate) is formed by spraying or coating the enzyme-containing liquid onto the carrier, such as in a fluid bed agglomerator. Here the resulting granules can include an agglomerate as can be produced in a fluid bed agglomerator.
Preferably the mixing of the enzyme-containing liquid and the solid carrier additionally comprises kneading of the mixture. This can improve the plasticity of the mixture in order to facilitate granulation (e.g., extrusion).
If the granulate is formed by extrusion this is preferably performed at low pressure. This can offer the advantage that the temperature of the mixture being extruded will not increase, or increases only slightly. Low-pressure extrusion includes; extrusion for example in a Fuji Paudal basket- or dome- extruder. Preferably extrusion does not result in the temperature of the material being extruded to rise above about 40xc2x0 C. The extrusion can naturally produce granules (the granules can break off after passage through a die) or a cutter can be employed.
Suitably the granules will have a water content of from about 30% to about 40%, such as from about 33% to about 37%. The enzyme content is preferably from about 3% to about 15%, such as from about 5% to about 12% (e.g., at least about 50,000 ppm).
The granules obtained desirably can be subjected to rounding off (e.g., spheronisation), such as in a spheromiser,.e.g., a MARUMERISER(trademark) machine and/or compaction. The granules preferably can be spheronised prior to drying since this can reduce dust formation in the final granulate and/or can facilitate any coating of the granulate.
The granules preferably can then be dried, such as in a fluid bed drier or, in case of the fluid bed agglomeration, desirably can be immediately dried (in the agglomerator) to obtain (solid dry) granulates. Other known methods for drying granules in the food, feed or enzyme industry can be used by the skilled person. Suitably the granulate is flowable.
The drying preferably takes place at a temperature of from about 25xc2x0 C. to about 60xc2x0 C., such as from about 30xc2x0 C. to about 50xc2x0 C. Here the drying can last from about 10 minutes to about several hours, such as from about 15 minutes to about 10 hours, preferably from about 15 minutes to about 3 hours, or desirably from about 15 minutes to about 30 minutes. The length of time required will of course depend on the amount of granules to be dried, but as a guide this is from about 1 to about 2 seconds per kg of granules.
After drying the granules, the resulting granulate preferably has a water content of from about 3% to about 10%, such as from about 5% to about 9%.
A coating preferably can be applied to the granulate to give additional (e.g., flavoured) characteristics or properties, like low dust content, colour, protection of the enzyme from the surrounding environment, different enzyme activities in one granulate, or a combination thereof. The granules can be coated with a fat, wax, polymer, salt, unguent and/or ointment or a coating (e.g., liquid) containing a (second) enzyme or a combination thereof. It will be apparent that if desired several layers of (different) coatings can be applied. To apply the coating(s) onto the granulates a number of known methods are available which include the use of a fluidised bed, a high shear granulator, a mixer granulator, or a Nauta-mixer.
In other embodiments additional ingredients can be incorporated into the granulate where desirable, e.g., as processing aids, for further improvement of the pelleting stability and/or the storage stability of the granulate. A number of such preferred additives are discussed below.
Salts preferably can be included in the granulate, (e.g., with the solid carrier or water). Preferably (as suggested in EP-A-0,758,018) inorganic salt(s) can be added, which can improve the processing and storage stability of the dry enzyme preparation. Preferred inorganic salts are water soluble. They can comprise a divalent cation, such as zinc (in particular), magnesium, and calcium. Sulphate is the most favoured anion although other anions resulting in water solubility can be used. The salts optionally can be added (e.g., to the mixture) in solid form. However, the salt(s) also desirably can be dissolved in the water or enzyme-containing liquid prior to mixing with the solid carrier. Suitably the salt is provided at an amount that is at least about 15% (w/w based on the enzyme), such as at least about 30%. However, it can be as high as at least about 60%, or even about 70%, for a maximum range of from about 15% to about 70% (again, w/w based on the enzyme). These amounts can apply either to the granules or to the granulate. The granulate therefore can comprise less than about 12% (w/w) of the salt, for example from about 2.5% to about 7.5% (w/w), e.g., from about 4% to about 6% (w/w).
If the salt is provided in the water then it can be in an amount of from about 5% to about 30% (w/w), such as from about 15% to about 25% (w/w).
Further improvement of the pelleting stability can be obtained where desirable by the incorporation of hydrophobic, gel-forming-or-slow dissolving (e.g., in water) compounds. These can be provided at from about 1% to about 10%, such as from about 2% to about 8%, and preferably from about 4% to about 6% by weight (based on the weight of water and solid carrier ingredients). Suitable substances include but are not limited to derivatised celluloses, such as HPMC (hydroxy-propyl-methyl-cellulose), CMC (carboxy-methyl-cellulose), HEC (hydroxy-ethyl-cellulose); polyvinyl alcohols (PVA); and/or edible oils. Edible oils, such as soy oil or canola oil or other appropriate oil, can be added (e.g., to the mixture to be granulated) as a processing aid, although often it will be preferred that the granulate does not contain any hydrophobic substances (e.g., palm oil).
Preferably the granules have a relatively narrow size distribution (e.g., they are monodisperse). This can facilitate a homogeneous distribution of the enzyme in the granules and/or the enzyme granulate in the animal feed. The process of the invention tends to produce granulates with a narrow size distribution. However, if necessary, an additional step can be included in the process to further narrow the size distribution of the granules, such as screening. The size distribution of the granulate is suitably between about 100 xcexcm and about 2000 xcexcm, preferably between about 200 xcexcm and 25 about 800 xcexcm, and optimally between about 300 xcexcm and about 1600 xcexcm. The granules can be of irregular (but preferably are regular) shape, for example, approximately spherical.
The water or enzyme-containing liquid can comprise one or more enzyme(s) and are usually of microbial origin, e.g., obtained from a microbial fermentation. Usually the enzyme will be in an active form (for example it may have catalytic or physiological activity). Preferably the liquid is in a concentrated form, such as an ultra-filtrate (UF), which can allow the production of a granulate with a desired activity level.
Suitable enzyme(s) are those to be included in animal feed which includes pet food. The function of these enzymes is often to improve the feed conversion rate, e.g., by reducing the viscosity or by reducing the anti-nutritional effect of certain feed compounds. Feed enzymes (such as phytase) can also be used, such as to reduce the amount of compounds which are harmful to the environment in the manure. Preferred enzymes for these purposes include but are not limited to: phosphatases, such as phytases (both 3-phytases and 6-phytases) and/or acid phosphatases; carbohydrases, such as amylolytic enzymes and plant cell wall degrading enzymes of which include cellulases such as xcex2-glucanases, hemicelluloses such as xylanases, or galactanases; peptidases, galactosidases, pectinases, esterases; proteases, preferably with a neutral and/or acidic pH optimum; and lipases, preferably phospholipases such as the mammalian pancreatic phospholipases A2.
Preferably, the enzyme does not include starch degrading enzymes (for example amylases). In some embodiments proteases desirably can be excluded as these may cause harm if ingested.
If the enzyme is a phosphatase, such as a phytase, then preferably the final granulate can have an activity of from about 5,000 to about 10,000 such as from about 6,000 to about 8,000, FTU/g. If the enzyme is a plant cell wall degrading enzyme, for example a cellulose, and in particular a hemicellulose such as xylanase, then the final granulate preferably can have an activity of the enzyme ranging from about 3,000 to about 100,000, preferably from about 5,000 to about 80,000, and optimally from about 8,000 to about 70,000, EXU/g. If the enzyme is a cellulose, such as xcex2-gluconase, then the final granulate desirably can have an enzyme activity of from about 500 to about 15,000, preferably from about 1,000 to about 10,000, and optimally from about 1,500 to about 7,000, BGU/g.
One FTU(phytase unit) is the amount of enzyme which liberates 1 micromole of inorganic phosphorus per minute from 0.0051 Mol/L of sodium-phytate at pH 5.5 and 37xc2x0 C. FTU can be calculated using any standard means, and, desirably, using the method of Engelen et al., Journal of AOAC International, 77 (3), 760-764 (xe2x80x9cSimple and Rapid Determination of Phytase Activityxe2x80x9d). One EXU (endoxylanase unit) is the amount of enzyme which liberates 1 micromole of reducing sugars (measured as xylose equivalents) per minute from a 1% xylan solution at pH 3.5 and 40xc2x0 C. One BGU (Betaglucanase unit) is the amount of enzyme which liberates 0.278 micromole reducing sugars (measured as glucose equivalents) per minute at pH 3.5 and 40xc2x0 C. at a substrate concentration of 0.5% betaglucan from barley. EXU and BGU can be calculated using any standard means, and desirably, using the method of Engelen et al., Journal of AOAC International, 79 (5); xe2x80x9cViscosimetric determination of xcex2-glucanase and endoxylanase activity in feedxe2x80x9d (1996). Even more preferably, FTU, EXU, and BGU are measured and determined as described in the Examples which follow (xe2x80x9cGeneral Materials and Methodsxe2x80x9d).
The granules desirably can comprise from about 5% to about 20%, e.g., from about 7% to about 15% of the enzyme(s). The enzyme can be naturally occurring or recombinant (i.e., including synthetic).
In addition to these enzymes the invention is equally applicable to polypeptides with other biological activities, such as antigenic determinants, for example, that find use in vaccines and/or polypeptides engineered to have an increased content of essential amino acids, of which the biological activity may be sensitive to thermal inactivation, and the term xe2x80x9cenzymexe2x80x9d as used herein is to be construed accordingly.
A preferred process according to the invention therefore comprises:
a. mixing the water, enzyme and solid carrier comprising at least about 15% (w/w) or an edible carbohydrate polymer, for example mixing the solid carrier with an aqueous enzyme-containing liquid;
b. optionally kneading the resulting mixture;
c. granulating, for example by mechanical processing, the mixture in order to obtain enzyme-containing granules, for example by using a granulator or by extrusion;
d. optionally spheronising the granules;
e. drying the resultant granules to obtain an enzyme-containing granulate.
During the entire process one desirably will aim to keep the maximum temperature to which the enzyme(s) are exposed to below about 80xc2x0 C. In particular, preferably mixing can be done at temperatures of from about 30xc2x0 C. to about 800xc2x0 C., and drying can be done at temperatures of from about 25xc2x0 C. to about 60xc2x0 C.
The granulates of the invention are suitable for use in the preparation of an animal feed. In such processes, the granulates desirably are mixed with feed substances, either as such, or as part of a premix. The characteristics of the granulates according to the invention allows their use as a component of a mixture which is well suited as an animal feed, especially if the mixture is steam treated and subsequently pelleted. The dried granules desirably can be visible or distinguishable in such pellets.
Thus a third preferred aspect of the present invention relates to a process for the preparation of animal feed, or a premix or precursor to an animal feed, the process preferably comprising mixing a granulate of the second aspect with one or more animal feed substances (e.g., seeds) or ingredients. This desirably can then be sterilised, e.g., subjected to heat treatment. The resulting composition is then suitably processed into pellets.
A fourth preferred aspect of the invention relates to a composition comprising a granulate of the second preferred aspect, which composition is preferably an edible feed composition such as an animal feed. This composition is preferably in the form of pellets (there can be from about 1 to about 5, e.g., from about 2 to about 4, dried granules per pellet).
The composition desirably can have a water content of from about 10% to about 20%, e.g., from about 12% to about 15%. The amount of enzyme(s) is suitably from about 0.0005% to about 0.0012%, such as at least about 5ppm.
Suitably the composition comprises from about 0.05 to about 2.0, such as from about 0.3 to about 1.0, optimally from about 0.4 to about 0.6 FTU/g of a phosphatase, e.g., a phytase. A xylanase can be present at from about 0.5 to about 50, e.g., from about 1 to about 40 EXU/g. Alternatively, or in addition, a cellulase can be present at from about 0.1 to about 1.0, e.g., from about 0.2 to about 0.4 BGU/g.
A fifth preferred aspect relates to a process for promoting the growth of an animal, the process comprising feeding an animal with a diet that comprises a granulate of the second aspect or a composition of the fourth aspect. Here, the animal diet can include either the granulate itself, or the granulate present in a feed.
A sixth preferred aspect of the present invention relates to the use of the granulate of the second preferred aspect in, or as a component of, an animal feed or for use in an animal diet.
A seventh preferred aspect of the present invention relates to the use of a composition comprising at least about 15% (w/w) of an edible carbohydrate polymer as a carrier for an enzyme to improve the pelleting stability of the enzyme.
Suitable animals include farm animals (e.g., pigs, poultry, livestock and the like), non-ruminants or monogastric animals (e.g., pigs, fowl, poultry, marine animals such as fish and the like), ruminants (e.g., bovine or ovine, such as cows, sheep, goats, deer, calves, lambs and the like). Poultry includes but is not limited to chickens, hens and turkeys.
Preferred features and characteristics of one aspect of the invention are equally applicable to another mutatis mutandis.

Carbohydrate-based enzyme-containing granules for use in animal feed


Data is stored on a tag unit. The tag unit provides for alert monitoring capabilities and monitoring of events, these capabilities allow for supply chain plans to be restructured and for events to be rescheduled. The tag unit is attached to an item for tracking purposes. The tag unit monitors and stores a status of the item. Then the item is sent to a destination. The tag unit is scanned when the item has been sent to a destination. The data on the tag unit is updated as a function of scanning. The data is updated when the tag unit is scanned at a destination. Then the data on the tag unit is validated. The data is validated for security purposes. The data on the tag unit is scanned to identify conditions to trigger actions. The system recovers from failure to read data on the tag unit by reconstructing the expected data from a history of the tag unit. Failure may be a result of identified or unidentified tempering of tag units, failure of the tag unit mechanism, or violation of the tag unit access limitations.

Pervasive and secure real-time supply chain situation awareness (i.e., where things are and when activities happen) maximizes the value of supply chain event response and adaptive supply chain management solutions.
Automatic identification and data collection (AIDC) systems may be used to track and identify items in batch or real-time. AIDC systems may allow for data collection through passive and active approaches. Passive approaches include bar codes and magnetic strips. Active approaches include global positioning systems (GPS) and real-time location systems (RTLS). Radio-frequency identification tag (RFID) systems may be active and/or passive.
RFID tags may be small tags that may be placed on containers, pallets, or even individual items. The ubiquity of RFID tags may allow for measurement of supply chain effectiveness to a very fine degree. RFID tags may allow for enhanced security and the ability to securely track and verify shipments.
Users of AIDC technologies have chosen a variety of different but complementary forms of AIDC to identify and collect data on items everywhere. Users have done this in an attempt to incorporate legacy systems into their AIDC efforts and to implement AIDC systems that are flexible and are not locked into a particular AIDC hardware platform. While the varying AIDC technologies are complementary in theory, in actual practice it may be incredibly difficult and costly to make such AIDC systems work seamlessly together.
It is an object of the method and system of the present invention to provide for a standard manner in which to deal with the myriad of devices and protocols that fall under AIDC technologies.

Method and system for collaborative and fail-tolerant deployment of automatic identification and data collection (AIDC) devices


Apparatus for handling hollow core rolls of different core diameters, by picking up a roll disposed with its axis vertical, relating the same to a horizontal position, and sliding it onto a horizontally extending spindle. A stepped diameter holder having sets of gripper elements is supported on an angled arm driven by a rotary actuator. After insertion of the stepped diameter into a roll core and outward movement of the gripper elements, the core can be moved to a horizontal orientation by oscillation of the actuator. The stepped diameter holder has a ball locking assembly which is inserted into a receptacle attached to the projecting end of the spindle. After full insertion sensed by blockage of air flow out of a hole in the end of an actuator rod caused by contact with a compressible insert, the actuator rod is moved axially to dock the spindle to the stepped holder by operation of the ball locking assembly and the gripper elements are released, allowing powered push off of the roll onto the spindle.

This invention concerns roll handling apparatus for hollow core rolls of a type disclosed in U.S. Pat. Nos. 4,708,574; 5,468,116; and 4,226,567.
In such apparatus, an internal gripper is inserted in the roll hollow core and gripper elements are expanded to engage the core. The roll can then be lifted by a hoist, and reoriented by a manual adjustment of an angled support arm.
Such apparatus is often used to load heavy rolls onto spindles of textile equipment or other similar machines. It has heretofore been considered desirable to have a xe2x80x9cdockingxe2x80x9d feature, in which the gripper is coupled to a receiving spindle prior to pushing the roll onto the spindle with a pusher cylinder.
The docking feature insures that the spindle and roll core are held together properly aligned and to prevent separation of the spindle and a roll holder when the roll is pushed onto the spindle.
In such prior art devices, the gripper has been comprised of a stepped diameter holder xe2x80x9cnosexe2x80x9d, adapted to be used with two different inside diameter roll cores, i.e., a three inch and six inch inside diameter core, each stepped diameter having a set of expanding fingers pushed out by axial movement of an actuator rod stroked by an air cylinder to grip the core.
The docking feature as previously practiced involved operating the three inch fingers to grip a spindle receptacle, when six inch rolls were being handled. This precluded xe2x80x9cdockingxe2x80x9d when only six inch core rolls were being handled.
In U.S. Pat. No. 4,708,574, the orientation of a roll has been carried out with an arm having an angled joint, the roll manually rotated about the joint to be reoriented. Powered reorientation using robots or complex and bulky linkages and power cylinders has been practiced.
It is also desirable to insure that docking and loading has been successfully completed during the process without relying solely on careful observations by an operator.
Accordingly, it is the object of the present invention to provide apparatus for handling rolls of the type described which allows docking with both size roll cores with stepped diameters.
It is a further object to provide an arrangement for insuring that docking and loading has taken place prior to releasing a gripped roll for transfer onto a spindle.
It is a still further object to make handling to reorient the rolls quicker and easier then with the manual methods previously practiced, without requiring bulky or complex equipment.
The above objects as well as others which will be understood upon a reading of the following specification and claims are accomplished by adding a locking ball assembly of smaller diameter than the smaller diameter of a stepped diameter holder for receiving roll cores to be handled, the ball locking assembly projecting from the end of the smallest diameter of the holder.
An actuator rod and air cylinder is used to spread and retract two sets of gripper elements by axial motion of the rod, each set actuated by the rod, which also passes within the ball sleeve assembly. When the stepped diameter holder is maneuvered towards the spindle, the actuator rod end is inserted into a receptacle fixed to the end of the spindle. A compressible insert is contacted when the rod end is fully inserted, blocking air flow out of an internal passage through the end of the rod. The resulting increase in pressure in the passage enables activation of the air cylinder to retract the rod, which releases the gripper elements and also forces the locking balls outwardly to engage the receptacle bore wall. Retraction of grippers releases the roll on the holder to allow the roll to be pushed onto the spindle with a pusher cylinder. Either diameter of the stepped holder may use these docking features.
An angled arm supports the stepped diameter holder, and a rotary actuator has an output shaft extending at the same angle and enables powered rotation of the angled arm to reorient a roll held on the stepped diameter holder.


The shear ram assembly 10 for shearing an oil well tubular T includes a first ram 16 axially moveable along the first axis 66 for moving an upper blade 17, and an opposing second ram 18 axially moveable along the second ram axis 68 for moving a lower blade 19. An upper planar surface 40 of the lower blade passes closely adjacent a lower planar surface 42 of the upper blade as the blades move towards each other to shear the tubular. The sealing system 24 is positioned within a recess 26 in the upper surface of the lower blade, and includes an elastomeric seal 28 for sealing engagement with the lower planar surface of the upper blade and a rigid actuator 30 moveable relative to the lower blade to energize the elastomeric seal.

The present invention relates to ram assemblies of the type used in the oil and gas industry and, more particularly, to a shear ram assembly which provides more reliable sealing between an upper blade and a lower blade.
Ram assemblies referred to as blowout preventers (xe2x80x9cBOPsxe2x80x9d) are commonly used in the oil and gas industry while exploring for and extracting hydrocarbons, such as oil and gas. One or more commonly two ram assemblies are used in series to cut off the flow from the well in an emergency. Some ram assemblies are intended to seal off an annulus surrounding a tubular, while other ram assemblies have the ability to both severe the tubular and seal in the well. Blades fixed to opposing shear rams may thus be driven together to completely shear the tubular. The lower portion of the severed tubular typically remains in the well beneath the shear rams, and the upper severed portion may be removed. The cut edge of the upper and lower tubular portions are sometimes referred to, respectively, as the upper and lower xe2x80x9cfish,xe2x80x9d and xe2x80x9cfishing toolsxe2x80x9d are used to retrieve the lower fish. A sealing element acting between the upper and lower shear blades or between each blade and the shear ram housing prevent fluid from escaping through the closed shear ram assembly.
Blade configurations and corresponding sealing elements for shear ram assemblies are numerous in the prior art. One general type of seal may be described as a face seal, in which a face or a leading edge of one or both rams comes to rest forcefully against a seal element after shearing. U.S. Pat. No. 3,561,526 describes a shear ram assembly which is intended to reduce the likelihood of damage to the sealing elements as a result of the shearing process. After the two rams sever the tubular, the rams continue to slide past one another until each ram presses against an opposing seal element. This creates two vertically spaced pressure seals, with a greater combined likelihood of reliable sealing than might be possible with just one seal.
In other shear rams, the sealing element is instead carried in the sliding face of the upper blade to seal between the blades after shearing. Although the cutting edge of the blade passes over the sealing element, which can damage the seal, this arrangement is preferred for many applications since the seal does not depend on a known final position for the blades. Numerous patents propose minimizing the risk of seal damage with this type of shear ram assembly. U.S. Pat. No. 4,540,046 is one example of a shear ram assembly comprising a seal actuator which actuates the seal into compressive engagement with the opposing blade only after the cutting edge of the blade has passed over the seal. U.S. Pat. No. 5,713,581 discloses a seal configuration designed to resist the damaging rollover of the seal element that may occur when one blade slides over the seal element. U.S. Pat. No. 4,347,898 discloses a shear ram assembly intended to withstand high forces tending to separate the blades without damage to the seal. U.S. Pat. No. 5,515,916 discloses shear rams in which a cross seal strip on one blade face is constructed and arranged to avoid being damaged by the other blade. Avoiding damage to the sealing element is clearly a fundamental concern for shear ram assemblies that seal between the blades.
Prior art shear ram assemblies thus include a seal element carried in the lower face of the upper blade. U.S. Pat. Nos. 4,540,046, 5,713,581, and 4,537,250 are examples of this type of configuration. One reason for this preference is the lower surface of the upper blade and thus the seal element is protected by the upper blade from dirt and debris. Furthermore, fluid pressure from the well beneath the rams helps energize the seal in those assemblies having an actuator bar, since fluid pressure from below acts on the actuator bar to further activate the seal.
In addition to protecting the sealing element, another primary concern associated with shear ram assemblies is the time and expense involved with maintenance. Millions of dollars are routinely spent in the operation of a wellhead, and downtime results in loss of revenues and profitability. The oil and gas industry is therefore interested in equipment that is less expensive and time consuming to operate. U.S. Pat. No. 5,360,061 discloses shearing rams which shear a tubing string in such a manner that a separate trip may not be required to prepare the upper fish left in the well bore prior to lowering an overshot to engage the upper end of the sheared tubing string. U.S. Pat. No. 5,400,857 discloses a shear ram assembly intended to minimize equipment costs and operating expenses. Other patents of interest include U.S. Pat. Nos. 4,341,264, 4,240,503, and 5,906,375.
The present invention surpasses the prior art, offering a shear ram assembly with an improved sealing system. The sealing system avoids the drawbacks of the prior art, particularly for those shear ram assemblies having a sealing element between the sliding blades.
The present invention relates to improvements in a shear ram assembly, which is commonly part of a BOP which contains an upper shear ram assembly and a lower pipe ram assembly. The tool joint of the oilfield tubular is conventionally hung off on the lower pipe rams once the upper shear ram assembly is actuated to shear the tubular. More particularly, the present invention relates to improvements in the location of the sealing system which seals between an upper shear blade and a lower shear blade of the shear ram assembly.
The shear ram assembly may thus be actuated to shear a tubular extending into a well and seal fluid pressure within the well. The assembly comprises a first ram axially moveable along a first axis for moving an upper blade, and an opposing second ram axially moveable along a second axis for moving a lower blade, with the first and second axes preferably being substantially coaxial and perpendicular to a centerline of the shear ram assembly, which coincides with a centerline of the tubular being sheared. The upper blade and the lower blade are each slidably moveable toward the centerline of the tubular, and at least one and optionally both of the upper blade and the lower blade include a shearing edge for shearing the tubular. An upper planar surface of the lower blade thus passes closely below a lower planar surface of the upper blade as the blades move toward each other in response to actuation of the first and second rams to shear the tubular. The sealing system is positioned substantially within a recess in the upper surface of the lower blade, and includes an elastomeric seal for sealing engagement with the lower planar surface of the upper blade and a rigid actuator moveable relative to the lower blade to energize the elastomeric seal.
In a preferred embodiment, the actuator includes an energization ramp for engagement with the upper blade as the blades move toward each other, such that the upper blade urges the actuator downward to compress the elastomeric seal, thereby energizing the elastomeric seal. The actuator preferably comprises an elongate actuator bar having a bar axis generally perpendicular to the centerline of the shear ram assembly. A retainer bar supported on the lower blade overlaps a portion of the actuator bar to restrict upward movement of the actuator bar.
It is an object of the present invention to provide an improved shear ram assembly wherein the sealing system is positioned substantially within a recess in the upper surface of the lower blade, such that the top edge of a lower fish does not contact and damage the elastomeric seal when the shear ram assembly is subsequently opened, thereby extending the useful life of the sealing system compared to a shear ram assembly wherein the elastomeric seal is provided in a lower surface of the upper blade.
It is a feature of the present invention that the lower surface of the upper blade may be hardened, preferably by a laser hardening process, to resist damage by the sheared tubular after the shearing operation, specifically when the shear ram assembly is opened.
A further feature of the invention is that the sealing system includes a leading anti-extrusion insert and a trailing anti-extrusion insert each adjacent an upper surface of the elastomeric seal to prevent pressurized extrusion of the elastomeric seal into a gap between the upper surface of the lower blade and the lower surface of the upper blade.
A related feature of the invention is that the upper blade includes a leading edge surface sloping upward from the lower surface of the upper blade to an upper blade edge for initially engaging the sealing system, thereby minimizing the likelihood of the upper blades damaging the sealing system.


A system and method for anchoring a tree is disclosed. A free end of an anchored guyline is looped around a tree. The guyline has been received through openings in the tension bar such that the tension bar is located between the anchored end of the guyline and tree. Tension is created within the guyline by pulling the tension bar. The tension bar and guyline are squeezed together and the guyline tied off at the tension bar.

This invention relates to anchoring a tree, and more particularly, this invention relates to a tree anchoring system and method using a guyline that can be tensioned and tied with minimal tools, complexity, and cost.
New trees that are recently planted must be anchored or staked. The trees are often tied by cables, ropes, and other guyline systems, such as disclosed in U.S. Pat. Nos. 6,301,830; 6,299,125; 6,237,289; 5,950,359; 5,649,788; 5,031,370; 4,802,317; and 4,222,198. Some of these systems have required a tensioning process using cables and turnbuckles similar to an aircraft cable system. Turnbuckle and similar tree anchoring systems require extensive manipulation with a tool or involve inordinate worker time to set up and maintain.
For example, U.S. Pat. No. 6,301,830 discloses a method for stabilizing trees by using a number of guylines and tension bars, which each have a tension adjustment opening having a diameter slightly greater than the diameter of the guyline and a keyhole opening. As the guylines are passed through the various openings in the tension bars, the ends of each tension bar are slid with the tension adjustment opening that bears along the respective guylines to place in compression a respective spring positioned in a limited spring extension assembly. Afterward, the tension bar is released. This is a complicated system requiring complicated use of a tension bar and spring. It is also time consuming.
Other prior art tree anchoring systems take as long as 30 minutes to anchor and tie down a tree. It is, therefore, desirable to tie down and anchor trees in an inexpensive manner that can be accomplished in a short period of time, such as in less than 10 minutes. This is important when hourly billing rates, including workmen""s compensation, can cost as much as $12.00 an hour and as high as $35.00 an hour in certain geographical areas of the country. These high billing rates can be billed to a customer at even higher rates, for example, up to about $65.00 an hour in some cases.
It is therefore an object of the present invention to provide a system and method for anchoring a tree that overcomes the disadvantages as noted above.
In accordance with the present invention, a system and method for anchoring a tree is disclosed. At least one ground anchor is driven into the ground at a selected location from the tree. A guyline has been secured to the ground anchor and has a free end. A tension bar, having two openings, has been received over the guyline through one opening such that the free end of the guyline is passed through the other opening after having been looped around the tree. In this manner, the tension bar is located between the ground anchor and tree. The tension bar is configured to be squeezed with the guyline and tied off using the free end of the guyline.
In one aspect of the present invention, the tension bar comprises a longitudinally extending bar member having opposing ends, each end having a hole through which the guyline passes. The bar member is configured to be grasped manually and pulled to create tension. The ground anchor preferably comprises a triangular shaped ground anchor and a drive rod is removably engaged to the ground anchor such that the drive rod is hammered for driving the ground anchor into the ground. It can be removed after the ground anchor is secured within the ground.
In yet another aspect of the present invention, the guyline is formed from a mesh material. At least three ground anchors have an attached guyline and tension bar for anchoring a tree by the three guylines. A protective collar on the guyline can protect the tree.
A method of the present invention is disclosed and comprises the step of looping a free end of an anchored guyline that also passes through an opening in a tension bar around a tree and through an open hole in the tension bar such that the tension bar is located between the anchored end of the guyline and the tree. The guyline is pulled to create tension within the guyline. This tension bar and guyline are squeezed together and the guyline is tied off with the anchor.
In another aspect of the present invention, tension is created within the guyline by pulling downward on the tension bar. In yet another aspect of the present invention, tension can be created within the guyline by pulling upward on the tension bar.
A stop knot can be tied with the free end of the guyline at the tension bar to allow pulling of the tension bar and adding tension to the guyline. The guyline can also be pulled after having passed the free end of the guyline through the open hole of the tension bar to take up initial slack within the guyline.
In yet another aspect of the present invention, the step of tying off the guyline with the anchor can further comprise the step of grabbing the tension bar with one hand and wrapping the loose end of the guyline around the two guyline sections above the tension bar. A knot can be tied such that the guyline sections do not separate for maintaining tension.
In yet another aspect of the present invention, the ground anchor is driven into the ground with the guyline is attached thereto to anchor the guyline. The ground anchor can be driven into the ground by hammering a removable drive rod against the ground anchor such that when the ground anchor has been driven to a desired depth into the ground, the drive rod is removed.
In another aspect of the present invention, a stop knot can be tied after having looped the guyline around the tree and tying at least one knot below the stop knot. The tension bar is pulled upward to create tension. The tension bar can also have opposing ends and opposing holes at each end through which the guyline is passed.


A leg supporting device for use behind a head rest for air and vehicular travel has a head rest support portion that fits over a head rest of a forwardly positioned seat and supports a back flap portion that hangs down behind the forwardly positioned seat. A pair of adjustment straps adjustably attach to the back flap portion and supports a foot support portion. A user slips one or both of their feet into the foot support portion and then adjusts the adjustment straps to support their feet at a desired height and position. The foot support portion handles to carry it. In use, the leg supporting device can be folded and placed within the foot support portion and carried using the handles until needed. One embodiment includes pockets for holding drinks, computer, and other carry-on items. A leg massage unit may be built in for additional relief.

Long distance travel by air and motor vehicle as a passenger without exercise and movement of the leg is associated with serious health risks. They are related to lower extremities which are the dependent lowest part of the body during these travels. Gravity and lack of exercise or movement of dependent legs during long air travel and vehicular travel are associated with ankle edema, venous blood pooling in dependent legs, deep vein thrombosis (DVT) of the leg veins, and pulmonary emboli (PE) if thrombus is dislodged from the leg vein, which can threaten the life.
All over the world especially in US, commercial air travel is one of the safest, reliable, dependable methods of transportation; short and long distances from one place to another. Millions of people of all ages take to the air every day. Due to super highways, the long travel in automobiles, passenger buses, SUVs, and recreation vehicles, traveling is part of our lives without breaking to exercise the leg and where the leg rests on the floor of the vehicle with untold discomfort to the passenger and with the leg swelling with or without deep vein thrombosis.
The environment within the aircraft and seating with hardly any space to move the lower limbs in the cabin may have adverse pathological effects on passengers, especially in the elderly and those with underlying medical problems (Voss M W. Air travel for the chronically ill and elderly. Am Fam Physician 1983; 27: 235-43).
The cramped up, overcrowded, confined, restricted conditions, prolonged immobility (particularly in long-air flights), constant noise and vibration, and intermittent air turbulence may be disturbing to the air (and surface vehicular as well: Bus rides, cars, SUVs and RVs) travelers. It can cause edema of the lower limbs (jet flight leg) which is the commonest complication of air travel; deep vein thrombosis (DVT) ('economy class syndrome') as a result of venous stasis in the dependent leg and Pulmonary Embolism (PE) if the thrombus gets loose and travels to the lungs through the venous highway of our body. There is a detailed review on the "air travel in older people" by James A. Low, Daniel K, Y. Chan in Age and Ageing 2002; 31: 17-22).
Physiological Effects of the Air Cabin on the Traveler
Air plane cabin pressure varies according to the altitude. Most commercial planes travel between 28,000 and 45,000 feet (flight altitude) above sea level with cabin pressures maintained between the equivalents of 6000 to 8000 feet (cabin altitude) above sea level. Cabin oxygen starts decreasing at altitude above 22,500 feet. At a cabin pressure of 6,000 feet, the alveolar oxygen tension is 71 mm Hg while at 8,000 feet it is 59 mm Hg (AMA Commission on Emergency Medical Services. Medical aspects of transportation aboard commercial aircraft. J Am Med Assoc. 1982; 247: 1007-11). At cruising altitude, cabin oxygenation is diminished and may pose a health risk to passengers with anemia, cardiopulmonary illnesses, emphysema, COPD, and other vascular conditions. This can result in carbon dioxide build up and acid metabolites accumulation due hypoxic metabolism (lactic acidosis) in the body further contributing to the pathology of leg edema and DVT.
Further, the low cabin pressure leads to expansion of gases in accordance with Boyle's law. If gas is trapped in body cavities such as the sinuses, middle ear, gut, pleural cavity, emphysematous bullae, eyes, tooth fillings, and skull, this can be hazardous to health due to difficulty equalizing air pressures within these enclosed areas of the body with the external environment. It can cause aerotitis media, barosinusitis, aerodontalgia, pneumothorax, transient ischemic attacks, nausea, and vomiting.
The air in the cabin has low humidity. The low humidity (usually below 25%) within the cabin may lead to dryness of exposed membranes (oropharynx and eye), which leads to dehydration, if the traveler is on a diuretic and the ingestion of many alcoholic drinks during the flight.
The overcrowded, confined, restricted conditions, prolonged immobility in long flights and surface travel, constant noise, and vibration of the plane; and intermittent air turbulence due to weather and altitude changes may be disturbing to travelers specially if the person is elderly (Rayman R E. Passenger safety, health and comfort: a review. Aviation Space Environ. Med. 1997; 68: 432-40). To top it all, prolonged air travel can cause edema of the lower limbs (jet flight leg) (Shuster S. Jet flight leg. Lancet 1996; 347: 832-3. James P B. 'Jet leg', pulmonary embolism and hypoxia. Lancet 1996; 347: 1697.), or deep vein thrombosis ('economy class syndrome') (Cruickshank J M, Gorlin R, Jennett B. Air travel and thrombotic episodes: the economy class syndrome. Lancet 1988; ii: 497-8.), as a result of venous stasis due to lack of leg muscle exercise which literally pumps blood towards the heart during contraction in the unidirectional valves of the leg veins.
Pulmonary embolism is now a well-recognized complication of long-haul air travel (Black J. Deep vein thrombosis and pulmonary embolism. Lancet 1993; 342: 352-3. Milne R. Venous thromboembolism and travel: is there an association. J R Coll Physicians Lond 1992; 1: 47-9. Lederman J A, Keshavarzian A. Acute pulmonary embolism following air travel. Postgrad Med J 1983; 59: 104-5).
A study of 56 victims of pulmonary embolism at Charles de Gaulle Airport found a direct correlation between the distance traveled and the likelihood of PE. About 85% of air travel thrombosis victims (DVT) are athletic, usually endurance-type athletes like marathoners. People with slower resting blood flow are at greater risk of stasis, stagnant blood subject to clotting. Also, they are more likely to have bruises and sore muscles during their athletic activities that can trigger clotting in the stagnated blood in the blood vessels of the lower extremities. It is estimated that chances of blood clotting in the leg veins is fifty times more in fliers compared to non-flying population.
Development of acute ischemia due to arterial thrombosis of the lower limbs from prolonged sitting is one the complications cannot be ignored (Teenan R P, McKay A J. Peripheral arterial thrombosis related to commercial airline flights. Br J Clin Pract 1992; 46: 165-166).
Hypoxia during flying can induce ischemic conditions of the heart, leading to acute myocardial infarction or stroke, or change in cognition. Older people may suffer the harmful effects of prolonged hypoxia without presenting overtly initially. The cardiac consequences of in-flight hypoxia include angina, acute myocardial infarction, and congestive cardiac failure (Anon. Illness in the clouds (editorial). Br Med J 1975; 1: 295). Cardiac conditions constitute the most common cause of in-flight deaths (Cummins R O, Chapman P J C, Chamberlain D A el al. In-Air flight deaths during commercial air travel. J Am Med Assoc. 1988; 258: 1983-8.).
PE deaths each year are numbered about 200,000. Several studies, such as a 4-year study at Tripler Army Medical Center in Hawaii, have concluded that 50% of DVT/PE cases are attributable to air travel. Of 200,000 PE deaths the 50% are due to air travel would be 100,000. This is a conservative estimate because it doesn't include stroke and heart attack deaths caused by air travel DVT. About 48% DVT victims later develop so called Postthromoteic syndrome (PTS) resulting in swelling and pain of the lower leg. Due to these lingering health risks due to air travel, precautions should be taken to prevent the leg swelling, and venous stasis in leg veins.
One of the most common in-flight medical emergencies is syncope (fainting fit) from a variety of causes (Cottrell J, Callaghan J, Kohn G el al. In-flight emergencies: one year of experience with the enhanced medical kit. J Am Med Assoc 1989; 262: 1653-6. Donaldson E, Pearn J. First aid in the air. Aust N Z J Med 1996; 66: 431-4. Schoken V, Lederer L. Unscheduled landings for medical reasons: a five year survey of the experience at American Airlines. In Busby D edited. Recent Advances in Aerospace Medicine. Dordrecht: Reidel, 1970; 126-9.).
Aircraft passengers, especially elderly travelers, are more prone to syncope because of prolonged sitting with pooling of the blood in dependent leg, dehydration and alcohol use if there is any which can lead to postural hypotension and syncope (Jagoda A, Pietrzak M. Medical emergencies in commercial air travel. Emerg Med Clin North Am 1997; 15: 251-60).
Economy Class Syndrome and Jet Leg Syndrome
The term 'economy class syndrome' refers to the development of deep vein thrombosis with subsequent pulmonary embolism in passengers travelling long distances in the cramped economy class seats. Unfortunately, the business class and first class travelers, pilots and air hostesses are not exempt from these risks. This term can be applied to the long distance bus rides, SUV, and car travel.
Those with predisposing medical conditions such as venous system disease (Varicose veins), advanced cancers, heart failure, atrial fibrillation, nephrotic syndrome, abnormally high hemoglobin (hematocrit) levels, hemochromatosis, liver cirrhosis, high platelet levels, leukemia, hypercoagulable disorders, women on hormonal therapy, history of recent surgery, and those with a history of thrombo-embolic illnesses are at a risk of developing this complication (Symington I A, Stack BHR. Pulmonary thromboembolism after travel. Br J Dis Chest 1977; 71: 138-40. Sarvesvaran R. Sudden natural deaths associated with commercial air travel. Med Sci Law 1986; 26: 35-8. Thomas J E P, Abson C P, Cairns N J W Pulmonary embolism: a hazard of air travel. Centr Afr J Med 1981; 27: 85-7).
Dependent leg with edema, pooling of venous blood in the legs, and DVT can result in pulmonary embolism (PE) due to air travel and journeys as short as 4 hours. DVT may present 1-2 weeks after the flight or long vehicular travel and is not necessarily preceded by a pain in the calf. Preventive Measures suggested include the use of pressure-graded elastic stockings (not elastic panty hose, they won't help), periodic muscle contracting exercises while seated using our invention, regular walks from the aisle seat (avoiding the window seat if possible), restrict excessive alcohol intake, and adequate (non-alcoholic) electrolyte fluid intake (Landgraff A. Economy class syndrome: theology, balance and lower leg edema during a simulated 12 hour long distance flight. Aviat Space Environ Med 1994; 65: 930-5).
Travelers with predisposing conditions who are at a high risk for thrombo-embolism; low-molecular-weight heparins, warfarin or low-dose aspirin may be taken prophylactically (The Pulmonary Embolism Prevention (PEP) (Trial Investigators. Prevention of pulmonary embolism and deep vein thrombosis with low dose aspirin. Lancet 2000; 355: 1295-302. Kay S. Safe air travel. Preventing in-flight medical problems. Nursing Pract 1994; 19: 43-6.). Leg edema ('Jet flight leg'), may mimic deep vein thrombosis, is more common in women, usually benign, resolves spontaneously and can be prevented by the use of appropriate elastic stockings, which should be worn before take-off to be effective as soon as you are seated in the plane and using our invention. They can be worn during long bus, car, and other vehicular rides also.
Air Cabin Effects on Body Gases of Passenger
The expansion of body gases within the low-pressure environment of the aircraft cabin can cause serious harm to health. Expansion of gases within the stomach and duodenum may lead to pain, discomfort, nausea, vomiting, splinting of the diaphragm, breathing difficulties, and even intestinal perforations. Hence, avoid gas-producing foods before travel and carbonated drinks during the flight. Those with recent abdominal (gastrointestinal and urological) surgery, gastrointestinal hemorrhage, or bowel obstruction should refrain from flying till health is restored (2-3 weeks after the event). For those with a colostomy, a larger bag should be used and carry a spare bag to the cabin. The trapped air in defective teeth fillings, apical abscesses and carious teeth can expand to cause toothache (aerodontalgia).
Cardiac conditions constitute the most common cause of in-flight deaths (Cummins R O, Chapman P J C, Chamberlain D A el al. In-Air flight deaths during commercial air travel. J Am Med Assoc 1988; 258: 1983-8.). Air travel should be avoided in those with new or unstable angina, history of recent myocardial infarct (within 3 months), poorly controlled congestive heart failure, malignant hypertension or severe anemia<8 g/dl), advanced COPD, severe lung fibrosis and cardiac asthenia.
Ear and Sinus Problems During Air Travel
Ear and sinus problems are the recurring complaints of the travelers during ascent and descent of the air plane. Earache can be serious and annoying in toddlers (crying due to pain). Otic barotrauma occurs in up to 9% of air travelers. It can present as acute ear pain, tinnitus, vertigo, or temporary hearing loss (Csortan E, Jones J, Haan M Brown M. Efficacy of pseudoephedrine for the prevention of barotraumas during air travel. Ann Emerg Med 1994; 23: 1324-7.).
Cabin pressure changes can be deleterious to passengers with middle ear and sinus problems. Failure to equalize pressure within the middle ear and the environment can cause otic barotrauma and potentially even tympanic membrane rupture with slight bleeding to external ear canal. A patent Eustachian tube is of paramount importance in equilibrating middle-ear pressure with the external environment. Individuals with acute otitis media, Eustachian blockage, and severe sinus problems; recently eye or brain surgery, lung surgery or laparascopic procedures are advised not to fly until the conditions are cleared. Passengers are advised to perform a Valsalva maneuver or to swallow repeatedly to prevent damage to the ear drum and open up the connection to the middle ear through the Eustachian tube.
Neurological Conditions and Effects of Air Travel
Seizures patients should be on medications and patients who have had strokes, after brain surgery or concussion within 4 weeks of occurrence should not travel to prevent further brain swelling and or recurrence during flight. Passengers (especially aged), due to prolonged sitting, dehydration and alcohol use, can lead to postural hypotension and develop Syncope (fainting).
Motion Sickness of Air Travelers
Air turbulence due to a linear vertical motion (during takeoff and landing descent) on the vestibular organ, psychological factors, and alcohol consumption can cause motion sickness, which can be incapacitating. Measures that can be used to reduce this problem include flying at night to reduce visual stimulation, sitting in a reclining position, seated away from the engines and toward the center of gravity of the aircraft, and taking prophylactic anti-motion medication during the flight such as anti-histamines and scopolamine patches.
Precautions for the Older Air Traveler
Due to aging of the population, the increased old age group travelling is increasing with resulting in multiple health-related medical emergencies in flight. In-flight medical emergencies can be reduced or averted with careful pre-flight planning and medical evaluation of those with many medical problems who are on multiple medications, those recently discharged from hospital, those with advanced chronic illness (such as heart failure or chronic airflow limitation) and those who are frail (Gong H Jr, Lee J A, Cowan M N.
Pre-flight medical screenings of patients. Analysis of health and flight characteristics. Chest 1993; 104: 788-94). All passengers over 65 who intend to fly for more than 6 hour should be screened for any health problems as a precautionary measure. Screening of patients susceptible to the adverse effects of hypoxia might include arterial blood gasses, an electrocardiogram, lung function tests, and measurement of serum hemoglobin concentration. All elderly people with memory or cognitive deficits are screened with the Mini-Mental State Examination. Those with early dementia may be more prone to developing delirium in flight.
The physician who deals with older patients should be able to offer advice, counseling, and screen those who are at risk and advice against travelling in certain situations (Table 1). Some recommendations are given in Table 2 if one has to travel.
There is a detailed review on the "air travel in older people" by JAMES A. Low, DANIEL K, Y. CHAN in Age and Ageing 2002; 31: 17-22; and has information for those who have to travel on long distance bus rides, recreation vehicles, SUV, and cars. The following tables are modified from this publication which acts as helpful guide lines for safe trip and to prevent leg swelling and deep vein thrombosis associated pulmonary emboli. Table I and Table II describe the health related contraindications and precautions to be taken if the travel is planned by the aged.
TABLE IContraindications to long-distance air travel speciallyfor the agedCARDIOVASCULAR SYSTEM1Heart attack within last 3 months2Chest pain due to unstable angina3Heart disease with uncontrolled congestive cardiac failure4Uninhibited cardiac dysrhythmias5and very high blood pressure (Malignant hypertension)RESPIRATORY SYSTEM1Air between the chest wall and lungs (pneumothorax)2Severe Emphysema with bullous (Air bubble pockets) disease3Vital capacity of <50%4Arterial P02 of <60 mmHg with oxygen at ground levelNEUROPSYCHIATRIC DISORDERS1stroke within last 4 weeks on anti-coagulants2Epilepsy - uncontrolled3Severe dementia with deliriumOTHERS HEALTH CONDITIONS1Severe anemia <8 g/dl)2Recent eye, abdominal or brain surgery (within last 2 weeks)3Serious sinus and middle ear infection
TABLE 2Recommendations for air travel specially to the agedBEFORE THE TRIP PREPARATIONS1Start preparations early - one to two weeks ahead2Consider travelling with family and groups3Foreign travel should include appropriate vaccinations3Take out adequate travel health and life insurance4Those with cardiopulmonary conditions, recent acute medical5Ask your doctor to prescribe anxiolytics for anxiety and6antihistamines for motion sickness to be taken before the Right7Involve in exercise program such as walking, swimming, cycling,tread mill etc.DURING THE FLIGHT OBSERVATIONS1Carry physical health aids2Carry medications in separate bag packed for easy accesses3If old, try to be seated along the aisle, away from the engines4Do not drink alcohol5Avoid gas-producing food such as beans you already know.6Avoid plain water, colas and drink electrolytes (Gatorade)containing fluids throughout the flight7Stop smoking a week or two ahead if you are habitual smoker8Once seated, take regular walks in the aisle and engage in legmuscle contracting movement exercises
If a blood clot dislodges from the leg veins due to movement of the leg after air flight and vehicular travel trek to the lung, which can cause pain, fainting, and even death. A clot in the leg is called deep vein thrombosis (DVT) and a clot in the lung is called pulmonary embolism (PE). Clots form in the arterial system and in the heart, leading to heart failure, and stroke about 2-3 weeks after travel.
DVT is usually mistaken for a cramp. Correct diagnosis and treatment is usually delayed which aggravates the injury and increases the risk of permanent vein damage and further injury or death when a clot travels to the lungs, brain, or heart. Airhealth.org says, "About 85 percent of air travel thrombosis victims are athletic, usually endurance-type athletes like marathoners. People with slower resting blood flow are at greater risk of stasis, stagnant blood subject to clotting. They are more likely to have bruises and sore muscles that can trigger clotting. Long bus and vehicular riders are not immune from this medical complication.
During air travel, blood coagulability (blood clotting) rises steadily and blood flow slows down, especially in the lower dependent part of the legs. Most of these clots are painless which some clots do cause pain and swelling. Blood clotting factors during a 9 hour flight (or vehicular rides) show noteworthy changes in blood chemistry.
Coagulation involves a complicated interplay between factors that produce fibrin versus factors that dissolve fibrin. DVT may appear during flight and vehicular travel or in the next few days. After 30 days you are probably safe. Watch for the following leg symptoms: 1. A little swelling in both leg is normal in flight but a sudden swelling in one lower leg is dangerous; 2. Cramp or tenderness in one of the calf muscles; 3. Bruise or swelling behind knee. Suspect PE if one develops the following: 1. Shortness of breath, 2. Rapid breathing, 3. Cramp in the side of chest wall, chest pain, sometimes accompanied by shoulder pain, painful breathing, 4. Fever, 5. Coughing up blood 6. Fainting (especially in older people).
Aspirin and clopidogrel (Plavix), are effective for arterial clotting and aggregation of platelets. They are not as effective for venous pooling and clotting. Low molecular weight heparin (Lovenox and Pinokinase) a new pharmacologic compounds effectively prevents blood clots during air travel.
Preventive Measures for Leg Swelling, DVT and PE
Frequent leg flexing and movement with contraction of the all the leg muscles is the best preventive for Air and long surface travels. The blood needs to be pressed through the one-way valve veins system by contractions of the thigh and calf muscle every 30 minutes and more often if you have RISK FACTORS.
Exercises:
1. Extend your leg and flex your ankles, pulling up and spreading your toes, then pushing down and curling the toes. If your shoes limit toe movement, make the effort and don't worry, or remove the shoes. Alternative: rotate the ankles, making circles in the air with your toes.
2. If there isn't room to extend your leg, start with your feet flat on the floor and push down and curl your toes while lifting your heels from the floor. Then, with your heels back on the floor, lift and spread your toes. Repeat this heel-toe cycle five times or more.
3. Exercise your thigh muscles by sitting with your feet flat on the floor and slide your feet forward a few inches, then slide back and repeat and extend the leg (if you have enough room), and isometrically flex thigh muscles.
Compression Stockings: Compression stockings have proven effective in controlled studies. Studies using ultrasound scans before and after air travel found 5% of air travelers without stockings developed clots. Matched groups wearing compression stockings did not develop clots. Compression stockings are not recommended for people with poor leg circulation caused by arterial insufficiency. Avoid elasticity along the entire length elastic "support" hose and use special graduated compression stockings which are tight at the ankle. The compression stockings helps keep fluids in circulation instead of collecting in the lower leg, causing the swelling that can make it difficult to get your shoes back on after a flight.
Hydration: In a study by Hamada, twenty test subjects drank plenty of water, one cup per hour, during a nine-hour flight. They developed significant increases in blood thickness and urine output. Blood samples from arms and lower leg were taken. Viscosity (thickness) increased in the lower leg, exactly where clots are likely to form. Twenty other people drinking an electrolytic beverage did not have increased blood viscosity and urine output.
According to Medline Plus "Electrolytes exist in the blood like acids, bases, and salts (such as sodium, calcium, potassium, chlorine, magnesium, and bicarbonate) and can be measured by laboratory studies of the blood serum." Glucose is a carbohydrate; not an electrolyte. Apparently drinking an electrolytic beverage is a much better choice for staying hydrated during air travel (Hamada, Koichiro et al—Effects of Hydration on Fluid Balance and Lower-Extremity Blood Viscosity during Long Airplane Flights. JAMA. 2002; 287:844-845. February 20). Airlines don't serve electrolytic beverages which you may have to bring your own. Drink one cup per hour, for an eight-hour flight you need 64 ounces.
Tips to Reduce Lower-leg Swelling during Travel
1. Prevent wearing tight stretched, unyielding, skin-tight.
2. Drink adequate fluid to keep your urine light in color.
3. Include an isotonic drink such as Gatorade, Snapple etc. Isotonic means a solution that has the same salt concentration as the normal cells of the body and the blood as opposed to a hypertonic solution or a hypotonic solution.
4. Attempt to move your leg and stretch your ankles every 30 minutes by a short walk if possible or moving the leg while sitting. Draw circles with your toes to rotate your ankles if you are stuck in one position and cannot walk.
5. Elevate your feet and leg when possible. This is where our inventions play a major role in preventing the leg swelling and its associated complications such as DVT, and pulmonary emboli. You can elevate the leg any level you want using the present invention during any long travel.
6. Stay away from alcohol and sedatives because they both promote inactivity.
7. Consider wearing proper compression stockings. Do not confuse compression stockings with support stockings.
8. Avoid sleeping with crossed leg on the seat.
Many, who travel regularly, do not take the above precautions. We made a survey and observation at the airport and bus ports, which we found hardly anyone wearing compression stockings or taking any other measures enumerated here. Drinking alcohol was common in the first and business class. Only one time, we found a lady exercising her body from head to toe in the economy class. Majority of the people who walked out after flying had swelling of the ankles especially the elderly and females. Many of them had difficulty in walking (limping) due to increased tightness of the shoes at the ankle and leg due to swelling.
There is a need for an device that positions and suspends the leg above the floor in a vehicle passenger seat that is positioned behind a head rest to allow free movements of the leg (i.e. muscle contractions) that are bent at the hip, knee, and ankle resulting in prevention of venous blood pooling responsible edema and for deep vein thrombosis.

Leg supporting device for use behind a head rest for air and vehicular travel


A combination x digital subscriber line (xDSL) and analog modem including a computer bus interface, codecs, an analog front end (AFE) for xDSL communications coupled to a plain old telephone service (POTS) line and a direct access arrangement (DAA) for analog communications also coupled to the POTS line. The modem is designed on a peripheral component interconnect (PCI) card. Generally, .+-.12, 5 and 3.3 volts are available for PCI components. Traditionally, the AFEs for non-PCI modems were designed to operate on .+-.12 volts for differential POTS line driving. For differential POTS line driving, the AFE typically requires a regulated voltage. However, .+-.12 volts supplied to PCI cards are typically not as well regulated as the 5 and 3.3 volts, and therefore the .+-.12 volts is generally unsuitable for PCI modem AFE design. Furthermore, in computers that operate in different power management modes, .+-.12 volts may not be available to the PCI card while 5 and/or 3.3 volts may be available to the PCI card in certain power management modes. In one embodiment, the AFE operates on 5 volts. Power for the modem is made available from other parts of the computer supply in these power management modes.

1. Field of the Invention
The present invention relates to modems in a computer system, and more specifically to an analog front end of a x Digital Subscriber Line (xDSL) modem.
2. Description of the Related Art
Improvements in computer hardware price/performance ratios during the last decade have caused major shifts in both home and office computing environments. Advances in semiconductor technology have enabled the appearance of personal computers with a computing power equivalent to supercomputers available a decade ago. Further, the advent of high performance audio and graphics subsystems have turned the personal computer into a multimedia device capable of delivering multimedia entertainment to the computer user.
Multimedia is a relatively new capability for computer systems. Multimedia refers to the delivery of information that combines different content formats. For example, these different formats may include a motion video, audio, still images, graphics, animation and text. Historically, magnetic media, such as floppy disk, was the medium of choice for providing multimedia content. Due to the limited storage capabilities of floppy disks, multimedia on floppy disks were limited to small programs such as unsophisticated games, with little graphics details and low quality sound.
Newer multimedia mediums such as compact disk-read only memory (CD-ROM) provide greater storage capabilities. In addition to games, CD-ROMs in the form of digital video disks (DVDs) contain full-length movies. While DVDs continue to exist, other means for providing multimedia to computer systems have become available and newer methods are being developed.
Another multimedia medium called the Internet, and more specifically the World Wide Web (WWW) has gained rapid acceptance among computer users. The WWW is a system of documents and multimedia files that can be retrieved and viewed by any person who has access to the Internet.
The WWW is simply a series a communications and protocols representative of information and documents that could be linked to other documents and stored on computers throughout the Internet. The users of the Internet can access documents or pages via program called a browser. Although earlier browsers were text-only, today's browsers offer windows-based icons, pull-down menus, bit-map graphics and telephone links to display hypertext documents. Furthermore, the web standard presents a system independent graphical user interface for users.
Due to its ability to tie together many disparate sources in its unified, easy to access interface, the WWW is rapidly gaining acceptance as an information delivery media. The accessibility of audio and image files such as video over the WWW is also enabling the Internet to become a central depository suitable for entertainment as well.
Historically, users accessed the Internet via a modem which coupled the computer to an Internet Service Provider (ISP) over a standard plain old telephone service (POTS) line. Originally designed for voice communications, the POTS lines include twisted copper wire pairs, amplifiers and filters. The copper wire pairs were strung from a telephone central office (CO) to various customer premises.
The CO is considered to be a first level switching facility. The COs are then connected to a higher level switching facility and these higher level switching facilities are connected to even higher level switching facilities. The connection of all of these switching facilities form a public switched telephone network (PSTN).
Besides the Internet, other multimedia sources are available to the computer user, such as video on demand, and live broadcasts. Video on demand typically refers to the ability to retrieve various video entertainment programming at the touch of a button. For example, such programming may include movies. Video on demand provides the user the convenience of watching a program at home at their own leisure. Live broadcasts are similar to video on demand, except the programs are live, e.g., a sporting event.
Historically, video on demand and live broadcast services, were provided to customers over the air or by video cables. Transmission over the air or via cable was needed because of the high band width requirements for such services. Typically, for instance, to obtain video on demand services, a customer would have to install a satellite dish for reception. Although satellite dish sizes have decreased over the years (0.3 meters), some customers may not be able to install the satellite dish due to city ordinances or neighborhood covenants. In addition, weather conditions such as snow and rain may affect satellite dish reception. Furthermore, satellite dish users require a clear line of sight between the satellite dish and satellite. Structures, such as trees or other buildings, may affect signal reception. Although not typically affected by weather conditions or line of sight requirements, video on demand via cable TV may not be available to the customer due to the high cost of running a cable to their premise, especially for customers living in rural areas.
An emerging standard known as x digital subscriber line (xDSL) is a modem technology that transforms ordinary POTS lines into high speed digital lines for ultra-fast data access. xDSL also enables access to the Internet, reception of video on demand, video catalogs, and live broadcasts, as well as exciting new interactive multimedia applications such as multi-player gaming.
The xDSL modem has, so far as is known, include an analog front end (AFE) for interfacing the modem to the POTS lines. The AFEs are traditionally powered by .+-.12 volt power supplies. The AFEs typically used .+-.12 volts for efficient differential POTS line driving. For xDSL modems designed on a peripheral component interconnect (PCI) card, operating on .+-.12 volts may not be desirable. For instance, although .+-.12, 5 and 3.3 volts are normally made available to the components on the PCI card, in certain computer modes, such as sleeping or low power modes, .+-.12 volts may not be available.
It is often desirable to have the modem operate even when the computer is in the sleeping mode or low power modes. In these modes, it might be desirable to have a fully operable modem to maintain a communications link with the other modem, else the communications link may drop out or fail. In addition, when the computer is operating in these modes, the modem may be able to receive data, such as electronic mail.
Furthermore, POTS line drivers typically require regulated voltages. Some voltages are not well regulated for PCI cards, e.g., .+-.12 volts might not be as well regulated as the 5 and 3.3 volt supplies. It might be possible to regulate the .+-.12 voltages on the PCI card, however, this would increase cost, and be subject to space constraints from already limited board real estate. In addition, .+-.12 voltages on the PCI card typically require additional power planes, which may result in additional board layers and subsequent introduction of additional noise.

5 volts single power supply ADSL analog front end design


An assembly for rotating and axially directing a high pressure spray hose and spray head to clean residue from the bores of thermal transfer tubes. The assembly includes a number of subassemblies that are concentrically aligned and mounted to rotate in synchrony and direct a high-pressure hose and spray head. A hose cleaning subassembly washes and/or brushes the hose exterior with a low-pressure spray. A hose drive assembly controls axial hose movement via driven gears and chains and four polyurethane pinch wheels that abut the hose. Spring tensioners control the wheel-to-hose pressure. A layering arm extends from a driven reel axle and stacks the hose in uniform layer onto an adjustable hub at a driven reel. The diameter of the reel hub can adjusted relative to an outer cage. The hose reel, axial hose drive and hose cleaner assemblies can be operated at speeds rotational speeds of 60 rpm to 650 rpm and whereby tubes from xc2xd to 6-inch diameters can be cleaned at rates of 1 to 80 feet per minute.

The present invention relates to cleaning equipment for tubes and piping and, in particular, to high-pressure water spray systems for cleaning the bores of tubes mounted in a variety of equipment, such as heat exchangers, falling pressure evaporators and the like.
Industrial piping systems of all types frequently require cleaning. A problem especially common to heat exchangers and evaporators is that over time the bore and exterior walls of the heat exchange tubes develop corrosion, scale and other undesired residue. The buildup of residue decreases and/or generally adversely effects the heat transfer efficiencies. Operating costs for fuel, in turn, increase.
Periodic maintenance is thus required to clean the tubes. Frequently the equipment must be taken off-line during maintenance. Such maintenance can be performed by plant personnel or outside contractors who are specially trained and use special purpose equipment to perform such tasks. It is desirable that any down time be minimized. The task is typically performed manually and is therefore costly and time consuming, especially for large heating and cooling plants.
A variety of techniques and types of equipment have been developed to clean the interior and exterior surfaces of pipes and particularly heat transfer tubes. Soot blowing and chemical shocking are two techniques. Another technique is to individually direct equipment into each tube to mechanically dislodge the residue from the tube walls. Some of the latter equipment uses rigid lances that either rotate and/or have rotating blades. U.S. Pat. No. 5,579,726 discloses a lance-based assembly that directs streams of high-pressure water to effect the cleaning. The latter system supports a rotating and axially directed lance from a frame that can be aligned to each tube.
High-pressure spray systems are also known that direct streams of water from a spray hose into each tube. Jetting Systems and Accessories, Inc. sells one such system under the brand name xe2x80x9cFLEX LANCERxe2x80x9d. Another system is sold by Gardner Denver Water Jetting Systems, Inc., Houston, Tex. under the name xe2x80x9cVxe2x80x9d Drum Rotary Line Cleaner. The latter system provides a high-pressure hose and spray nozzle that are rotated and axially directed under power. Hose movement is directed with a hand-operated air controller and a pinch roller assembly that controls axial hose movement. Rotational movement is controlled via a separate motor. The hose is collected and dispensed from a rotating V-shaped spool or drum. Although offering advantages, the efficiency of the latter system is severely restricted by vibrations that occur due to unbalanced conditions that can occur at the equipment during typical use. Extreme vibrations have particularly been experienced at speeds approaching 60 rpm, which severely limits the utility of the equipment.
The present invention was developed to provide a more efficient high-pressure spray system. The assembly provides a hose mounted spray head that can be operated at rotational speeds in the range of 60 rpm to 850 rpm. Axial speeds in the ranges of 1 foot per minute to 80 feet per minute are also possible. At a nominal rotary speed of 300 rpm and an axial speed of 60 feet per minute the assembly is able to clean a typical 36-foot tube in one-fourth the time as the foregoing equipment.
The assembly is constructed to provide optimal balance along the entire drive train. The assembly also cleans the exterior surface of the spray hose as it is dispensed and collected from a driven spool or reel assembly. The reel assembly stacks the hosing in a tapered coil that is balanced to the longitudinal drive axis of the hose drive train. The hub of the reel assembly can be adjusted to accommodate different lengths and diameters of hose.
It is accordingly a primary object of the invention to provide a high-pressure tube cleaning assembly wherein a spray hose and spray nozzle can be directed at high rotational and axial rates by the assembly as the nozzle is directed through each tube being cleaned.
It is a further object of the invention to provide an assembly that includes a rotationally driven hose reel that arranges the spray hose in a fashion that avoids unbalancing the equipment relative to a longitudinal, rotational drive axis.
It is a further object of the invention to provide a hose reel having a conically tapered, hose collection hub mounted adjacent to a concentric outer cage and on which hub the hose is stacked in coils concentrically aligned to the longitudinal drive axis.
It is a further object of the invention to provide a hose cleaning assembly that cleans the hose as it is dispensed and collected.
It is a further object of the invention to provide a rotary mounted, air-controlled hose drive assembly having four polyurethane pinch-type drive wheels that axially direct the hose along the assembly""s longitudinal drive axis and that is rotationally balanced relative to a hose reel.
It is a further object of the invention to provide a drive axle at the hose reel that is coupled to the hose drive assembly and from which axle a layering arm extends that aligns the hose relative to an adjustable hub at the hose reel.
It is a further object of the invention to provide a hose collection hub wherein the diameter and taper of the hose collection hub can be adjusted relative to the outer cage and center drive axle.
The foregoing objects, advantages and distinctions of the invention, among others, are obtained in the following disclosed tube cleaning assembly that has been particularly adapted for use in cleaning heat exchangers and falling tube evaporators. The invention can be adapted to other applications wherein the tool head is coupled to a high-speed, rotationally and axially directed supply conduit.
The subject tube cleaning assembly provides a mobile framework that attaches to on-site air and water supplies. The assembly includes a number of subassemblies that are concentrically aligned along a longitudinal drive axis to direct a high-pressure hose and spray head. The subassemblies are mounted to rotate in controlled synchrony at a number of pillow block bearings.
At a fore end, the hose and orifice containing spray head are directed through a hose cleaning subassembly that washes the hose with a low-pressure spray. The hose is axially directed to and fro with an air-controlled hose drive assembly. A hand-operated valve directs air to an air swivel and a pair of drive motors. Drive power is applied to a pair of driven gears and chains to follower gears attached to four polyurethane pinch wheels that abut the hose. Spring tensioners control the wheel-to-hose pressure and are able to axially direct the hose at speeds of 1 to 80 feet per minute.
The hose drive is coupled to a hose collection reel via a motor driven reel axle. A layering arm extends from the axle and directs the hose onto an adjustable hub at the reel. The hose is preferably stacked in a single layer. A swivel at the opposite end of the reel axle supplies high-pressure water in the range of 3,000 psi to 50,000 psi to the hose.
The diameter of the hub at the hose reel can adjusted relative to an outer cage. The layering arm and hub cooperate to stack the hose in concentric layers relative to the longitudinal drive axis of the assembly to assure a balanced loading. The reel, axial hose drive and hose cleaner assemblies can be operated at rotational speeds in the range of 60 rpm to 650 rpm. The assembly is thereby able to clean tubes from xc2xd to 6-inch diameters at rates of 1 to 80 feet per minute.
Still other objects, advantages, distinctions and constructions of the invention will become more apparent from the following description with respect to the appended drawings. Similar components and assemblies are referred to in the various drawings with similar alphanumeric reference characters. Various features of the invention may also be configured with other features in different combinations. The description should therefore not be literally construed in limitation of the invention. Rather, the invention should be interpreted within the broad scope of the further appended claims.