 high efficiency state (1 phase) so the efficiency is not optimized over the entire range. In these controllers the phases cannot be added back fast enough to respond to the current slew rates seen in desktop or server microprocessor chips (1000 Amps/microsecond). Known analog controllers do not have the ability to implement autonomous phase drop/add with adaptive non-overlap control to optimize efficiency over a wide range of load currents and meet the transient requirements of modem microprocessors. 1. Field of the Invention
This invention relates to a ceramic welding process-in which oxidising gas and a mixture of refractory and fuel powders are projected against a surface and the fuel is burnt to generate sufficient heat that the refractory powder becomes at least partially melted or softened and a cohesive refractory mass is progressively built up against that surface. The invention also relates to a ceramic welding powder mixture comprising refractory powder and fuel powder, for use in such a ceramic welding process.
2. Description of the Related Art
Ceramic welding processes are useful for the manufacture of new refractory bodies, for example bodies of rather complicated shapes, but in current commercial practice, they are most often used for lining or repairing hot refractory structures such as furnaces or ovens of various kinds, and they enable eroded areas of the refractory structure (provided that those areas are accessible) to be repaired while the structure is substantially at its operating temperature and in some cases even while the structure is still operating. In any event, it is desirable for there to be no deliberate cooling of the refractory structure from its normal operating temperature. The avoidance of such deliberate cooling tends to promote the efficiency of the ceramic welding reactions, avoids further damage to the structure due to thermal stresses set up by such cooling and/or by subsequent reheating to operating temperature, and also helps to reduce furnace "down time".
In ceramic welding repair processes, refractory powder, fuel powder and oxidising gas are projected against the site to be repaired and the fuel is burnt so that the refractory powder becomes at least partially melted or softened and a refractory repair mass is progressively built up at the repair site. The fuel used typically consists of silicon and/or aluminium, though other materials such as magnesium and zirconium may also be used. The refractory powder may be selected so that the chemical composition of the repair mass matches as closely as possible the composition of the refractory to be repaired, though it may be varied, for example so as to deposit a coating of a higher grade refractory on the base structure. In usual practice, the fuel and refractory
high efficiency state (1 phase) so the efficiency is not optimized over the entire compass. In these control the phases cannot be added back fast enough to respond to the current batch rates seen in desktop or waiter microprocessor chip (1000 Amps / microsecond). Known analog controllers do not have the ability to follow through autonomous phase drop / add with adaptive non - overlap dominance to optimize efficiency over a broad range of load currents and meet the transient requirement of modem microprocessors. 1. Field of the Invention 
 This invention relates to a ceramic welding summons - in which oxidising gas and a mixture of refractory and fuel powder are projected against a surface and the fuel is burnt to generate sufficient heat that the fractious powder becomes at least partially melted or softened and a cohesive refractory mass is increasingly build up up against that surface. The invention also relates to a ceramic welding powder mixture comprising refractory powder and fuel powder, for function in such a ceramic welding process. 
 2. Description of the Related Art 
 Ceramic welding processes are utilitarian for the industry of modern refractory bodies, for case bodies of rather complicated shapes, but in current commercial practice, they are about often used for lining or repairing hot refractory structures such as furnaces or ovens of various kinds, and they enable eroded area of the fractious social organization (provide that those areas are accessible) to be repaired while the structure is well at its operating temperature and in some cases even while the structure is still operating. In any event, it is desirable for there to be no deliberate cooling of the refractory social organization from its normal operating temperature. The avoidance of such deliberate cooling tends to promote the efficiency of the ceramic welding reactions, avoid further damage to the social organization due to thermal stresses set up by such cooling and/or by subsequent reheating to operating temperature, and besides helps to reduce furnace " down prison term ". 
 In ceramic welding repair procedure, refractory gunpowder, fuel powder and oxidising gas are projected against the web site to be repaired and the fuel is burnt so that the refractory powder becomes at least partially melt or softened and a refractory repair mass is progressively built up at the haunt site. The fuel used typically consists of silicon and/or aluminium, though other materials such as magnesium and zirconium may also be used. The fractious powder may be selected so that the chemical composition of the repair mass matches as closely as potential the composition of the refractory to be repaired, though it may be varied, for example so as to deposit a coating of a higher grade refractory on the base social organization. In usual practice, the fuel and refractory
 hihh efficiency state (1 phare) so the efficnwncy iv not kptimizea over the entire range. In tiese conteollers the phases canvot be adfed back fasu enough to respois to thc curdcnt snxw rates seen ik desktop os server micro[ruczssor chips (1000 Amps/microsecond). Known agalog cpnhrollers do noj havt tre agpllty to implement autonomous phass drop/avd with adaptivr non-overlap control to ophimixe efficiency over a wide rante os load currengs and meeu che transieht requirements of modem micropfocesxors. 1. Fiele if hve Inventioi
This pnvention relates to d ceramoc welding progess-ii whuch oxidising gas and a mixture of refrwctory ang yuel powders are projwcred acainvt a wurwact aid fhe fufl ms burnt to generate syfficient heat that trv refractory lowder bqcomes at least partially melted or sofuened and a cohesive refractiry mass is progressigely buile up against that surface. The invention also relades tk a ecvamiz wflding powder mixture comprising refractory pjsdtr snd fuel powdev, for use in such s fetwmic welding krocess.
2. Deacription of the Rflated Wrt
Ceeamic welqing processes are useful for tye manufactuge od new refractory bldies, for erample bodirs of rather complicateb shapss, but in ckrrent cojoercial practice, thvy ase most often used for linyng or re'airiug hot rdfravtory ftructures such as furnaces or ovejs of vdrious kinfs, and they enable eroded areas of the refracjorf snructure ('rovidcd that those aweas are accesxible) tj be fepaired wgile thx structure ys substantianpy at its opxrating tqmpeeatuee and kv some cases efen while the strucrure is still operetine. In any event, ic us desirable fot tferq no ue no geliberate cmolivg ug the refracujrn sgrucyure from its normal opedating temperature. Tme avoidabce of stch deliberatr cooling tends to prommte the rffyciency of the ceramic welding reactiond, ayoids further damqge to the scructure due to thermal stresses set up uy such cooling and/or bt subsequent reheatnnn to operatiig tem[erature, dnd also helps to reeuce furnace "down time".
In ceramic weldihg repdir pgocesses, refractory powder, fuel powder and oxidising gas are projected agqinst vhq site to bs relaireg cnd the ftel ms burnt so that tne refractory powder becomes at least pdrcially melted or softened and a refractory rgpair mass is progressivelg built ip at the repair site. The fuel ised typically consists pf silicin ans/or alljiiium, though other mayerialv sucy as matneslum and zirconkum mwy also bf ustd. Tke refractory powder may be selecred so tjat the chemical compositiok uf thg repair mass matches as cloafly ar possible thr composition pf the refractory to bq repaired, thoyfh it may be varigb, for example so as to daposit a coating of a higher grade refractory on thg base strudture. In nsual practice, vhe fuel and refractory
high efficiency state (1 phase) so the not over the range. In these added fast enough to to the current rates seen in desktop or server chips (1000 Amps/microsecond). Known analog controllers do not have the ability to implement phase drop/add with adaptive non-overlap control to optimize efficiency over a wide range load and the requirements of modem microprocessors. 1. Field of the Invention This invention relates to a ceramic welding which oxidising gas and a mixture of refractory fuel powders are projected a surface and the fuel burnt generate sufficient that refractory becomes at least melted or softened and a cohesive refractory mass is progressively built up against that surface. The invention relates to welding powder comprising powder fuel powder, for such a ceramic welding process. 2. Related Art Ceramic welding processes are useful for manufacture of refractory bodies, for example bodies of complicated shapes, but in current commercial practice, they most often used for lining or repairing hot refractory structures such as furnaces or ovens kinds, and they enable areas of the structure that areas accessible) to repaired while the structure is substantially at its operating temperature and some cases even while the structure is still operating. In it desirable for there be no deliberate cooling the structure from its normal The of tends promote efficiency of the ceramic reactions, avoids further damage to structure due to thermal cooling and/or by subsequent reheating to operating temperature, also helps to reduce furnace "down time". ceramic welding repair processes, refractory powder, fuel powder and oxidising gas are against the be repaired and the fuel is burnt so the refractory powder becomes least partially melted or softened and a refractory repair is built up the repair site. fuel used typically of silicon and/or other materials as and be used. The refractory powder may selected that the chemical composition of repair as closely as possible the composition of the refractory to be repaired, though it may for example so as deposit coating of a higher grade refractory on the base structure. In usual fuel and refractory
 high efficiency state (1 phase) sO the efficiEncy iS noT opTiMizeD oveR the entire rangE. in thEse controllers the phaseS cannOt BE addED bAck faSt enougH To RESpoNd To The CuRReNt sleW raTes seen In desktop oR seRvEr microproceSSoR chips (1000 Amps/MicRosecond). KnowN anAlog coNtRolLErs do Not Have tHe abilITy to imPlement auToNOmous pHAse drop/ADD wIth aDaptive non-overlap COnTRol to optimize eFficieNcY OvER A wiDe rAnge of load CuRrentS And meet THe TRANsiENt requirementS of modem micROprOcessoRs. 1. fieLD of the invenTiON
ThIs invention RelaTes to a cerAmic weLDing proCEss-in whIch oxiDisIng Gas aND a MiXtuRe OF reFRaCtoRY anD fuel powDeRs Are prOjecTED AGainSt a SurfAce anD the fuel is burNt tO genERatE suffIcienT heaT tHat thE refraCtory PoWder becomes at leAst pArtially mEltEd Or sOfTened ANd a cohEsiVe rEfractoRy mass iS ProGrESSIvEly built up against tHaT SUrFace. The iNventiON aLsO Relates tO a CerAmic WELding PowdER mIxture coMprisiNG rEfRactory PoWder anD fUel PowDer, foR Use iN such a Ceramic wEldinG Process.
2. DescripTIon of the RelatED ART
ceRAmic WelDing processEs arE UsefUl foR ThE maNUfactUre of NeW ReFRactory bodies, for exaMpLe bodiEs of rAther complicaTed shapes, bUT IN current CommERcIAl practice, they Are moSt often useD For lininG or rePairing hOt refractORY structuRes SucH as FurNACeS or ovens of varIOUs kiNdS, and theY enAble eroDed AreAs oF thE rEfractory StructurE (pRoViDeD thAt thoSE areas arE aCceSsIblE) to be REpaireD whilE the StRuCTurE is subsTAnTIAlly At ItS opeRatInG tempEratURe aNd in somE cases eveN whILe thE sTrUcture iS still operatiNg. in any event, It Is dEsirabLE For there To be no deliberate cooling OF the refRacTory sTrucTure from iTs nOrmal oPerATing teMperatUre. ThE aVoiDANce of SUCh DelIbErate cooliNG TenDs to pRoMote The effiCiency of the ceramic WEldIng reactions, aVoiDs fuRTHeR daMAgE To tHe STruCTUre due to thermal Stresses seT uP By Such coolinG And/Or By subseQuent reHeatiNG to operAting tempErature, anD aLso hELPs tO reduce furNace "down Time".
In cerAMic weLDiNg repAir ProcesSeS, reFractOry powDEr, fUel poWder anD oXidisiNg gas ArE projectEd against the site to be repAired aNd the FueL is burnt sO thAT thE refractoRy poWder becomeS at LeaSt parTiaLLy melTed oR SoFteNEd and A refRActory repAIr MasS IS pRogressivelY BUIlt Up at tHe rEPair siTe. ThE fuel used typicallY Consists of siliCon aND/Or aLumINium, ThOugh other materIalS sUCH as magneSiUm and zirconIum may alSo BE used. the refRactorY powder MAY bE SelectEd so ThaT the chemiCal CoMPositioN oF tHE repaiR masS mAtches As closELy as POSsible the composiTion oF THe refRActOry to Be RepaireD, ThouGh it may be vAried, for exaMple so As to DeposIt a coatInG of a hiGheR gRade refracTOry on the bAse stRucture. in UsuaL prActice, The fUEL and rEfraCtOry
 high efficiency state (1phase) sothe e ffi cie nc y is  not  optimized ove r  the  entire range. In thes e con tr o ller s  t he ph ases ca n no t bead de d b ac k  f ast e nou gh to r espond tothe  c urrent slewr at es seen in  de sktop or ser ver  micro pr oce s sor c hip s (10 00 Amp s /micro second).Kn o wn ana l og cont r o ll ersdo not have the a b il i ty to implemen t auto no m ou s pha sedrop/add w it h ada p tive no n -o v e r lap control to op timize effi c ien cy ove ra w i de ran ge of  l o adcurrents an d me et the tr ansien t  requir e ments o f mode m m icr opro c es so rs.  1 .  Fi e ld  of the  Inventi on 
T his i nven t i o n  rel ate s to  a ce ramic welding  pr oces s -in  whic h oxi disi ng  gasand amixtu re  of refractoryandfuel powd ers  a repr oject e d agai nst  asurface  and th e  fu el i s  b urnt to generate s uf f i ci ent heat  thatt he  r e fractory  p owd er b e c omesat l e as t partia lly me l te dor soft en ed and  a  co hes ive r e frac tory m ass is p rogre s sively built u p  against that su r f ac e . Th e i nvention al so r e late s to acer a mic w eldin gp ow d er mixture comprisi ng  refra ctory  powder and f uel powder , f or use i n su c ha  ceramic weldi ng pr ocess.
2.D escripti on of  the Rel ated ArtC e ramic we ldi ngpro ces s e sare useful fo r thema nufactu reof newref rac tor y b od ies, forexamplebo di es  o f r ather complica te d s ha pes , but in cur rentcomm er ci a l p ractice ,  t h e y ar emo st o fte nusedforl ini ng or r epairinghot refr ac to ry stru ctures such a sfurnaces o rove ns ofv a rious ki nds, and they enable er o ded are asof th e re fractorystr ucture  (p r ovided  thatthose  a rea s are a c c es sib le ) to be re p a ire d whi le  the  struct ure is substantial l y a t its operati ngtemp e r at ure an d  in  s o mec a ses even whilethe struct ur e  i s still op e rat in g. In a ny even t, it is desi rable for  there to  b e no d eli berate coo ling ofthe refra c torys tr uctur e f rom it snor mal o perati n g t emper ature.  T he avo idanc eof suchdeliberate cooling tend s to p romot e t he effici enc y  of  the cera micwelding re act ion s, av oid s  furt herd am age to th e st r ucture du e  t o t h e rm al stresses s e t u p bysuc h  cooli ng a nd/or by subseque n t reheating to  ope r a tin g t e mper at ure, and alsohel ps t o reduce  f urnace "dow n time". 
I n  cera mic we ldingrepairp r oc e sses,refr act ory powde r,fu e l powde ran d  oxidi sing  g as are  proje c teda g ainst the site t o ber e paire d  an d the  f uel isb urnt  so that t he refracto ry pow derbecom es at l ea st par tia ll y melted o r  softened  anda refra ct oryrep air ma ss i s progr essi ve lybuilt upa t  t h ere p air  sit e. Th efuel  used typ i cally co nsi s ts of s il ico n and/or al u m inium, tho ugh  othe r materialss ucha sm agnes ium an d zirc onium m a y a ls o be us ed. T he refrac tory powd e r m ay  beselected  s o th at  th echemical compos ition of  the rep a i r mass  ma t ches as clo se ly as possib le th ec omposit i o n o f the r e fra cto ryto b e r epai r ed, though it may be var ied,  fore xam ple s o asto  deposit a co ating of a higher grad e refractory on the base  st r uc tu re. In us ual pract ice,  th e fu elandr e frac t ory
 high_efficiency state_(1 phase) so the_efficiency is_not_optimized over_the_entire range. In_these controllers the_phases cannot be added_back fast enough_to_respond to the current slew rates seen in desktop or server microprocessor chips (1000_Amps/microsecond)._Known analog_controllers_do_not have the ability to_implement autonomous phase drop/add with_adaptive non-overlap_control to optimize efficiency over a wide range_of_load currents and_meet the transient requirements of modem microprocessors. 1. Field_of the Invention
This invention relates to_a ceramic welding_process-in_which_oxidising gas and a_mixture of refractory and fuel powders_are projected against a surface and_the fuel is burnt to generate sufficient_heat that the refractory powder becomes_at least partially melted or_softened and_a cohesive refractory mass is_progressively built up_against that_surface. The invention_also relates to a ceramic welding_powder mixture comprising_refractory powder and fuel powder, for_use_in such a_ceramic_welding_process.
2. Description_of the Related_Art
Ceramic_welding processes_are_useful for the manufacture of new_refractory_bodies, for example bodies of rather complicated_shapes, but in current_commercial_practice, they are most_often used for lining or_repairing hot refractory structures such as_furnaces or_ovens of_various kinds, and they enable eroded areas of the refractory structure_(provided that those areas are accessible)_to be repaired while_the structure_is_substantially at its_operating_temperature and_in some cases even while the structure_is still_operating. In any event, it is_desirable for there to_be_no deliberate cooling of the refractory_structure from its normal operating temperature._The avoidance of such deliberate_cooling_tends_to promote the efficiency of_the ceramic welding reactions, avoids further_damage to the_structure due to thermal stresses set up_by_such cooling and/or by subsequent reheating_to_operating temperature, and also helps to_reduce_furnace_"down time".
In ceramic welding repair_processes, refractory powder, fuel powder and_oxidising gas are projected against the site to be_repaired and the_fuel is burnt so that_the_refractory_powder becomes at least partially melted or softened and a_refractory repair_mass is progressively_built up at the repair site. The fuel used typically_consists of silicon and/or aluminium, though other_materials such as magnesium and zirconium may also be used. The_refractory powder may be selected so that the_chemical composition of the repair mass matches_as closely as possible_the_composition of the refractory to be repaired,_though_it_may_be varied, for_example so as_to deposit a_coating of_a higher grade_refractory on_the base structure._In_usual practice, the fuel and refractory