API RP 11AR pdf download.Recommended Practice for Care and Use of Subsurface Pumps 3 History 3.1 The first formal work toward development of API Std 11A was in 1924. In that year, a Committee on Standardiza- tion of Pumping Equipment and Engines was organized. The first issue of API Std 11A, Specification for Cold Drawn and Machined Working Barrels for...