Coupling Sleeve is a sleeve-shaped rock drilling component with internal threads for connecting shank adapter and drill rod, or drill rod and drill rod. We produce and provide three types of drill rod couplings – semi bridge couplings, full bridge couplings, and crossover couplings, which can meet the requirements of all applications.

Standard coupling sleeve

Standard coupling sleeve, also known as semi bridge coupling sleeve, has a section of the bridge without a thread in the middle. The threaded part of the drill pipe cannot be screwed through the bridge part of the coupling, and the end of the thread can closely adhere to the casing bridge zone. Standard coupling sleeve is particularly suitable for high-torque drilling rigs. Most rope thread (R thread) and trapezoidal thread (T thread) coupling sleeves are with half-bridge type. The half-bridge type is by far the most widely used couplings.

Full bridge coupling sleeve

Full bridge coupling sleeve can completely eliminate the looseness of the coupling sleeves along with the threaded connection. It is mainly used in surface mining, with better disassembly characteristics, firmer connections, and almost no clamping situation.

Crossover couplings

Crossover couplings are used to convert different thread types or thread diameter sizes.

Applications

Coupling Sleeve
Thread	Diameter		Length
	mm	inch	mm	inch
R25	35	1 19/50	150	5 9/10
R28	40	1 29/50	155	6 1/10
R32	45	1 3/4	170	6 57/64
R38	55	2 5/32	170	6 57/64
T38	55	2 5/32	190	7 33/64
T45	63	2 15/32	210	8 17/64
T45	66	2 19/32	210	8 17/64
T51	72	2 7/8	235	9 1/4
T51	76	3	235	9 1/4

Adapter Coupling / Crossover Coupling
Thread		Diameter		Length
A	B	mm	inch	mm	inch
R25	R32	45	1 3/4	170	6 57/64
R28	R32	45	1 3/4	170	6 57/64
R32	R38	55	2 5/32	180	7 1/8
R32	T38	55	2 5/32	180	7 1/8
R38	T38	55	2 5/32	190	7 33/64