The sucker rod couplings are used for connecting sucker rods, polished rods and sinker bars. Material of the couplings is high quality carbon steel or alloy steel, which are conform to and exceed the requirements of API Specification 11B. The main types of ShengjiPetro rod couplings include sucker rod couplings, polished rod couplings and sub-couplings.
The main types of ShengjiPetro rod couplings include sucker rod couplings, polished rod couplings and sub-couplings. The Sucker rod coupling has same box thread size in both ends. The polished coupling is designed to connecting polished rod and sinker bars. The sub-coupling is also called cross over coupling. It has different box thread size in both ends.
According to different needs, ShengjiPetro provides users couplings under different processes. All of the three types have two surface treatment classes: class T and class SM. The class T stands for through-hardened and the class SM stands for sprayed metal. The outer diameter of the sucker rod couplings has FS(full size) and SM(slim hole) types.
According to surface of suck rod couplings, they can be divided into sucker rod couplings with smooth surface and sucker rod couplings with wrench square.
Good corrosion and wear resistance.
Black oxide coated for anti-galling and lubricating properties.
Automatic flame spray production minimizes the tolerance.
The sucker rod couplings are used for connecting the sucker rod and sinker bars with the same dimensions. But it is not used in the polished rods, which may cause the fracture of the couplings.
The polished couplings are designed to connect the polished rod and sinker bars.
The sub-coupling is widely used for the connection of different sizes of sucker rod, pony rod and sinker bars.