BACKGROUND 
       [0001]    In the drilling and completion industry, the formation of boreholes for the purpose of recovering hydrocarbons necessarily is accompanied by sand. Sand control therefore is a significant concern for operators and must be addressed in the downhole environment prior to its production with target fluids. This is because flowing sand is damaging to production equipment from the standpoint of erosion and further because it can adversely affect other equipment such as pumps, etc. Also notable is that the production of sand from the formation in which a borehole exists will tend to enlarge the borehole and increase the probability of cave ins, wash outs, etc., that would require remedial activity at not insignificant cost both in actual dollars and in lost production time. 
         [0002]    The art is therefore very concerned with sand control and has developed a plethora of types of sand screen and such to mitigate the problem. In view of ever changing conditions and techniques however, the art is always in need of and receptive to alternative arrangements. 
       BRIEF DESCRIPTION 
       [0003]    A sand screen includes a base pipe; a plurality of individual segments having complementary perimetrically interlocking shapes configured to be nested together so as to limit relative movement among the elements and to form a tubular filtration media about the base pipe; end rings engaging the filtration media and the base pipe. 
         [0004]    A building component for a sand screen including a segment; a plurality of merlons and a plurality of crenels at one longitudinal end of the segment; a plurality of merlons and a plurality of crenels at an opposite longitudinal end of the segment, the merlons being configured and dimensioned to be received in a crenel of a mating segment such that adjacent side surfaces of each mated merlon will form a passageway therebetween. 
         [0005]    A sand screen cartridge includes a plurality of individual segments having complementary perimetrically interlocking shapes configured to be nested together so as to limit relative movement among the elements and to form a tubular filtration media; end rings engaging the filtration media and the base pipe; and a shroud spanning the filtration media and affixed to the end rings. 
         [0006]    A sand screen including a base pipe; a plurality of individual segments having complementary perimetrically interlocking shapes configured to be nested together so as to limit relative movement among the elements and to form a first tubular filtration media about the base pipe; another plurality of individual segments having complementary perimetrically interlocking shapes configured to be nested together so as to limit relative movement among the elements and to form a second tubular filtration media about the base pipe stacked adjacent the first tubular filtration media; end rings engaging the first and second filtration media and the base pipe; and a shroud spanning the first and second filtration medias. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike: 
           [0008]      FIG. 1  is a perspective view of a segment for a sand screen as disclosed herein; 
           [0009]      FIG. 2  is a schematic view of the segment of  FIG. 1  illustrating side surface angles of merlons; 
           [0010]      FIG. 3  is another schematic view of the segment of  FIG. 1  illustrating side surface angles of merlons; 
           [0011]      FIG. 4  is a schematic view of a passageway through side surfaces of adjacent merlons; 
           [0012]      FIG. 5  is a schematic perspective view of a sand screen as disclosed herein; and 
           [0013]      FIG. 6  is a schematic perspective view of a sand screen having multiple sand screen cartridges thereon. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures. 
         [0015]    Referring to  FIG. 1 , a single segment  10  is illustrated. In this embodiment, the segment is a closed annular form (e.g. a ring) but part annular forms are also contemplated. In some embodiments the segments are constructed of hard erosion resistant material and may be a ceramic material. Other hard metal or plastic is also contemplated. If indeed a ceramic material is selected, the material may comprise for example Sintered Boron Carbide, Silicon Carbide, etc. 
         [0016]    Still referring to  FIG. 1 , segment  10  is castellated on both longitudinal ends  12  and  14 , the axis defining longitudinal in this case. The castellation in direction  12  is a mirror image longitudinally from the castellation in direction  14 . It is to be understood however, that it is not required that the castellations be mirrored end to end but to be appreciated that the castellation may be different in shape, different in register relative to castellations on the opposite end, etc. Rather what is important is that a plurality of the segments need to nest together to form a tubular structure that presents pathways for fluid to move therethrough. This can be accomplished with mirror imaged configuration as illustrated or with more complexity with other configurations. An advantage of the segments being mirror images on each end or at least mirrored shapes on both ends is that the plurality of segments may be identical to each other allowing for easy assembly into the tubular form without need to ensure the right segments are nesting with the right other segments. Rather each will nest identically with the next. It should also be appreciated that although a cylindrical shape of the segments is illustrated, other tubular shapes are also contemplated. 
         [0017]    Still referring to  FIG. 1 , standoffs  16  are illustrated at an inside surface  18  of the segment  10 . These may be of any number but likely not fewer than three and function to provide a drainage gap between the plurality of segments and a basepipe around which they will be positioned when the sand screen is assembled (see  FIG. 4 ). In other words, the standoffs  16  will abut an outside surface of the basepipe and ensure that the inside surface  18  of the plurality of segments  10  will not contact the outside surface of the basepipe. 
         [0018]    Also to be noted though relatively small in  FIG. 1  (more easily seen in  FIGS. 2 and 3 ) is a keying feature such as an offset  20 , of which there are two in each crenel  22  of the segment  10  as illustrated. It is to be understood that this is but one embodiment of a configuration to ensure that the nested segments  10  (creating a filtration media  11 ) register properly with one another to ensure that the intended fluid passageways will be substantially uniformly distributed. Other offset or key and keyway type arrangements may be substituted while achieving the same results. Barring a configuration providing for this registration function, the segments might turn relative to one another thereby creating a larger passageway on one side of a castellation that intended and a smaller one on the other side of the same castellation. This would reduce functionality of the sand screen. 
         [0019]    Referring to  FIGS. 1, 2 and 3  together enlarged views will improve understanding of the features mentioned and facilitate description of the shape of the castellations themselves. In one embodiment of the segment  10  the castellations comprise a number of trapezoidal merlons  24  interspaced by crenels  22 . In some embodiments, like the one illustrated, the merlons and crenels are sized to fit within each other or nest. Specifically, a crown surface  26  is configured to fit with crenel base surface  28 , between the offsets  20 . During construction of the sand screen, the crown surfaces  26  of each of the segments  10  to be used are coated with a resilient sealer such as a rubber or similar and will seal with surface  28 . At the sides of the merlons however, the surfaces  30 , it is intended that passageways  32  be formed, see  FIG. 4 . For this purpose, the side surfaces  30  are dimensioned and configured to be spaced apart from an adjacent merlon when the segments are nested together. This is accomplished in part by the offsets  20  and in part by the dimensions of the merlon itself relative to the dimensions of the crenel. The crenel  22  is slightly wider than the merlon that extends thereinto when nested. Further, in some embodiments it is desirable to have surfaces  30  when nested be parallel to each other, although it is certainly possible and in some cases could be desirable to have diverging or converging passageways simply by adjusting the angle of the surfaces  30 . In order to effect a parallel result, the actual radial angle of the surface  30  relative to a radial line drawn from the axis of the segment is about 1 degree different than the radial line resulting in a narrower merlon toward the inner surface of the segment than at the outer surface of the segment. A longitudinal angle of surface  30  of the trapezoid of merlon  24  is selectable as desired and in some embodiments ranges from about 0.5 degrees to about 10 degrees. The greater the angle, the longer the particular flow passageway. For some iterations of the segments  10 , the greater angle may provide for more flow area but it is also to be appreciated that a smaller angle coupled with more merlons  24  may provide an even greater total flow area even though the individual flow passageways would be shorter in length. 
         [0020]    Referring to  FIG. 5 , an assembled sand screen comprising a plurality of segments nested together (the filtration media  11 ) is illustrated. End rings  34  are also illustrated that in some embodiments are rubbery type material and configured to mate with a last of a plurality of segments on an axial end of a stack of such segments (filtration media  11 ) as shown. The end rings  34  have an inside diameter that is close to an outside diameter of a base pipe  36  to which they are mated. In some embodiments there will also be a metal backup  38  that may be welded to the base pipe  36  to help retain the other components in place. And finally, an optional shroud  40  is shown radially outwardly placed of the stacked segments and welded to the metal backups  38  and/or affixed to the end rings  34  by for example swaging. In the first instance, because a base pipe  36  is included, the welding of the shroud to the backups  38  will keep it in place. In the second instance however, while the affixation to the end rings  34  may be used with a basepipe, it further facilitates the construction of a sand screen cartridge  39  comprising the plurality of segments  10  (filtration media  11 ), the end rings  34  and the shroud  40  but without the base pipe. Embodiments directed to cartridges may optionally also contain backups  38  welded to the shroud  40 . The cartridge embodiments allow for an additional marketing opportunity as the sand screen cartridge may be sold and transported without a basepipe and thence may be installed on a base pipe at the well site or some other location that is convenient. 
         [0021]    In another embodiment, referring to  FIG. 6 , the shroud  40  is a unifying component for a number of individual cartridges  39 . More specifically, the filtration media  11  and end rings may be assembled in, for example only, 18 inch increments and then other of that same construction (or even other lengths) stacked adjacent each other on a base pipe, all of which are spanned by a single shroud. This would provide a more flexible sand screen and may simplify shipping since the sand screen cartridges would be small and relatively light weight when compared to a complete sand screen including the base pipe. It also would allow an operator to make a sand screen as long as is needed for the specific application by stacking cartridge segments to the desired length and cutting or extending the shroud to span them. 
         [0022]    The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should further be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity). 
         [0023]    The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a wellbore, and/or equipment in the wellbore, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc. 
         [0024]    While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited.
A sand screen including a base pipe. A plurality of individual segments having complementary perimetrically interlocking shapes configured to be nested together so as to limit relative movement among the elements and to form a tubular filtration media about the base pipe. End rings engaging the filtration media and the base pipe.