Patent attributes
A shear coupling can be used with reciprocating and rotary pumps. The shear coupling uses a shear nut and connecting member as the shear element. The connecting member and shear nut are located inside the axial bore of the shear coupling to protect from corrosive wellbore elements. The coupling members may be connected by matching polygonal shaft and hub profiles on the coupling members to transmit torque. The shaft and hub may have octagonal profiles for better torque transmission capacity. The shear nut may be isolated from large alternating stresses due to pretensioning of the connecting member. The length of the connecting member, especially when pretensioned, and a reduced cross-section that may be formed on the outer surface of the shear coupling increase the overall flexibility of the shear coupling, thereby increasing the resistance to bending stress.
