This paper discusses the use of fluids with densities less than that of water as a circulating medium in horizontal wells. The significance of inclined geometry as a determinant of pressure loss and hole cleaning efficiency is discussed as are the results of laboratory simulations.

This paper ,:;oncerns a cooperative effort between a major producing company and a major service company to establish a business relationship which emphasizes workmanship and productivity instead of traditional unit pricing. The general concepts of and reasons for productivity-based contracts are explored. The viability of these concepts for six common maintenance services are discussed as well as specific results from more than two years of operating experience relating to routine production maintenance (well servicing).

Of PstrolwmEnginwirsI Mark Rankin, POOL Co.; Bruce Lowe, Coastal Management Corp.; and Vernon Disney and Kirk Spilman, Texas A&MU. @P@@t 1~. Sd8fy of PatmlaumEnginaara,Inc. This paper we preparedfor preeantationat the Prdiotion OperationsSympoeiumhetd in OklahomaCity, OK, U.S.A., 24 April 1SS5, Thm paper wee ealactadfor praaanfationby an SpE ProgramOommitfaatallowingraviaw of informationoonfainedin an ebetmoteubmHtedby the author(a).Cmtenta of tha paper, = -nti, have not bean dewed by the SooWYof Petdeum En@ewe and are aubpf to oormofionby me author(a).The materiel,ea praeanted,d-not neoeaedty Mad Y -~of the SOOMYof PefmIeumErwkmam ifs offiim, a+rMM8t8. Pepem preeentedat SPE rnednga em aub@cfto publicationreviewby EditorialGmmMeea of the Sdefy dPGum EWi-. Pmbtitiqb~~tom~dti~~~~.llltiba~ti~@.~~~MGn-wa~~~m of wham andbywhomthe -r lapraaantad.Write Ubmrian, SPE, P.O. Sox S3S63S,Nohwdeon, TX 75W3-SWS, U.S.A. Telex, 1S3245 SPEUT.