API Spec 11B PDF

This specification provides the requirements and guidelines for the design of thread form requirements, steel sucker rods and pony rods, fiber reinforced plastic (FRP) sucker rods and pony rods, sinker bars, polished rods, couplings and sub-couplings, thread gauges, pumping tees, stuffing boxes, polished rod clamps, calibration of measuring equipment, standard methods of mechanical properties testing, and polished rod liners as defined for use in the sucker rod lift method for the petroleum and natural gas industry. 

Normative Annexes B through K specify equipment requirements, normative Annexes L through M provide for the calibration of measuring equipment and mechanical properties testing requirements, and informative Annexes N through P provide illustrations for polished rod liners, representative examples of discontinuities, and a sucker rod pumping system.