Patent attributes
A shock mounted top drive comprising a traveling frame for moving along a drilling tower, the traveling frame comprising a first and second housing section, at least one set of sheaves mounted to the upper section of each housing section, a guide wheel assembly secured to the outboard side of each housing section, at least one swivel support disposed on the inboard side of each housing section, at least one shock absorber disposed on each swivel support, and at least one upper stop connected to the inboard side of each housing section. A top drive power swivel, which has a housing and a rotating drive shaft, is secured to the traveling frame using a plurality of removable top drive retainers. The top drive retainers engage the inboard side of each housing section between the upper stops and the shock absorbers.