Patent ID: 8152412

Claim:
A pipelayer comprising: an undercarriage having at least two tracks, each track comprising: a track frame coupled to the undercarriage, and a track shoe supported by and movable around the track frame; and a main assembly supported by the undercarriage and rotatable relative thereto, the main assembly comprising: a main frame, a boom pivotally mounted to the main frame, an operator cab, a cab riser connecting the operator cab to the main frame, the cab riser operable to selectively raise and lower the operator cab relative to the main frame, the cab riser comprising: a riser base movably attached to the main frame; a lift mechanism adapted to selectively raise and lower the riser base; a guide mechanism for insuring proper alignment and travel of the riser base; and a height lock adapted to mechanically connect the riser base to the main frame at one or more selected positions, the height lock being operable to retain the riser base at the selected height independent of the operation of the lift mechanism.