T38 190mm Top Hammer Threaded Pipe Joint Coupling SleevesDescription Couplings sleeve are used to well connect the shank adapter to the drill rods or well contact two extension rods for transmitting energy. other name is Coupling, when using rock drills with male shank adapters and a conventional drifter rod, a coupling is required to join the adapter to the rod, ensuring the ends touch for efficient energy transmission. Couplings are also used to connect several rods to each other in the same way. Couplings have a middle stop to prevent over-threading on to the drill rod. We can manufactures semi-bridge, full bridge coupling sleeves for the percussive tools. We can manufactures semi-bridge, full bridge coupling sleeves for the percussive tools. Semi-Bridge Coupling sleeve - Small non-threaded bridge in the center - Steel cannot thread past bridge area - Smaller diameter steel end portions fit together in the centre bridge area of the coupling - Semi-bridged couplings are most suited to high torque machines - Most rope and T threaded couplings are semi-bridged Full-Bridge Coupling sleeve - Eliminates the potential for the coupling to creep along the threaded joints - Typically used in surface applications - Better uncoupling characteristics and tend to maintain tighter joints - Less chance of jamming - Best suited to machines equipped with independent rotation (i. E., S36IR rock drill) It has standard type coupling and crossover coupling.