They are designed to transmit torque from the surface to the rotor of the pump when using progressing cavity pumps. The dimensions and materials are in full compliance with API spec. 11B. Sucker rod materials and their physical-mechanical characteristics are according to API spec 11B. Sucker rods are usually delivered as fitted with full size class t couplings with normal outer diameter and without wrench flats. By request sucker rods can be fitted with other types of couplings.
General dimensions and tolerances for steel sucker rods and pony rods are according to API specification 11B.
Non rotating centralizer
Use of the NETZSCH centralizer minimizes the rod and tubing wear considerably. This special non-rotating centralizer acts like a bearing and centralizes the rod string inside the tubing. The centralizer consists oft two pieces: polished shaft rotating in the fixed non-rotating sleeve.