APPARATUS FOR POSITIONING A TONG AND DRILLING RIG PROVIDED WITH SUCH AN APPARATUS

摘要

An apparatus for positioning a tong comprises a piston and cylinder assembly (101) and a mounting assembly (102) therefor. The mounting assembly (102) is mounted on a support beam in the drilling derrick and the piston and cylinder assembly (101) is pivotally mounted on the mounting assembly. The piston and cylinder assembly (101) can be pivoted between an operative position in which it can be extended and retracted to move a tong towards and away from a string of tubulars, and an inoperative position in which the piston and cylinder assembly (101) extends along an upwardly extending axis with part of the piston and cylinder assembly (101) disposed to either side of the mounting assembly (102).