Brian Conner is the oil and gas industry product manager at R+W Coupling Technology. He may be reached at email@example.com. For more information on R+W’s redesigned line of disc pack couplings, including the API-610-compliant LPA and LPAI couplings, visit the website at rw-america.com or call 888-479-8728.
The friction drive design of this company’s disc pack couplings serves to eliminate the bending load that can be placed on the shoulder bolts in some traditional designs. The bolts in this particular design are tightened through the hubs, spacers, guard rings and bushings to a torque level sufficient enough to generate the necessary clamping pressure across the faces of the disc packs to transmit all of the power by friction. The frictional connection of the disc packs further increases service life, while making the complete coupling assembly more torsionally stiff.
The safety catch to retain the spacer in the unlikely event of a disc pack rupture on this design consists of a guard ring assembly that captures the center member by piloting the coupling hub to the guard ring itself. In the event of a disc pack rupture, the guard rings serve to contain the tube and prevent it from being thrown from the assembly.
This design also helps to ensure that the center spacer assembly with captured disc packs can be easily removed for maintenance of items such as seals and rotors without disturbing the adjacent components. The scalloped hub and guard ring aims to eliminate unnecessary material from the coupling, resulting in a lower inertia design.