Patent ID: 8267448

Claim:
A backup tong comprising: a body with a central opening for receiving a tubular body; a fixed jaw assembly mounted on the backup tong body for engagement with the tubular body; a sliding jaw assembly mounted on the backup tong body for sliding engagement with the tubular body; an activating mechanism for advancing the sliding jaw assembly onto engagement with the tubular body positioned within the opening, the activating mechanism comprising: (a) a cam arm which pivots around a fixed pivot point on the body of the backup tong, the cam arm comprising a first extension and second extension; the first extension having a cam surface on an edge face portion thereof, the cam surface in contact with the sliding jaw assembly thereby defining a point of contact on the cam surface; the cam surface comprising a rapid surface portion for rapid advancement of the sliding jaw assembly and a slow surface portion for slow advancement of the sliding jaw assembly; and (b) an actuating mechanism for providing rotation of the cam arm about the pivot point, the actuating mechanism mounted on the tong body and connected to the second extension; wherein upon rotation of the cam arm by the actuating mechanism, the point of connection first traverses along the rapid surface portion and then the slow surface portion, resulting in rapid advancement of the sliding jaw assembly upon initial approach towards the tubular body, followed by slow advancement of the sliding jaw assembly upon close approach and engagement with the tubular body.