Naša spoločnosť vyrábala spojky vrátane spojky prísavnej tyče, pomocnej spojky a sprejovej spojky, sú navrhnuté podľa normy API Spec 11 B. Použitie vysoko kvalitnej uhlíkovej ocele alebo legovanej ocele (ekvivalent AISI 1045 a AISI 4135) a pokovovanie je a kind of surface hardening technology, is the nickel, chromium, boron and silicon powder coated on the substrate metal and fused with the laser processing, after the process, the metal surface makes tvrdšie, hustota vyššia a rovnomernejšia, koeficient trenia je veľmi nízky a odolnosť proti korózii je veľmi vysoká. Slim hole (SH) diameter and standard size (FS) of conventional sucker rod and polished rod have plating metal (SM) .Under normal circumstances, there is two wrench on the coupling and the outside circle, but according to user we can also provide no wrench square.Hardness of coupling T is HRA56-62 after heat treatment, with good corrosion resistance and wear resistance, when using sucker rod coupling,is connecting with the same size rod, sub-coupling is used for connecting to difference size of the sucker rod or connect the polished rod and rod string .Coupling type: Class T (full size and slim hole ) ,Class SM (full size and slim hole ).