APPARATUS FOR PREVENTING SEPARATION OF DOWNHOLE MOTOR FROM DRILLSTRING

摘要

A downhole motor for a drillstring has a housing with upper and lower portions coupled to one another A rotor in the lower portion has an outward tapered receptacle at one end An extension is coupled to the rotor and is disposed relative to a seat in the housing An outer body of the extension has an external shoulder to engage the seat with separation of the upper and lower housing portions. An end of this outer body is disposed in the outward tapered receptacle of the rotor and defines an internal taper tapering inward in an internal passage of the body. An inner body is inserted into the internal passage of the outer body An end of the inner body wedges the internal inward taper at the end of the outer body into the outward tapered receptacle on the rotor to hold the extension on the rotor Should the lower housing portion separate from the upper housing portion, the shoulder on the extension can engage the seat so that the motor does not fully separate.