Threaded Pipe Coupling 1:Wherever needed. 2:Small torque of operate. 3:Long ... Socket-weld fittings in shape of Elbow,tee,Union,cross,Coupling,Cap,Bush,Plug,Swage nipple,Welding Boss,Hexagon nipple,Weldolets ... , the above parameters for reference only. Forged Steel Threaded Pipe Coupling