Patent attributes
A wrench for making up or breaking up a pipe joint is provided. The wrench comprises a tong assembly having an upper tong and a lower tong. The upper tong has a first upper tong half pivotably connected to a second upper tong half at their first ends. The lower tong has a first lower tong half pivotably connected to a second lower tong half at their first ends. A central bearing operatively couples the upper tong and the lower tong to allow the upper tong to rotate relative to the lower tong or vice versa. The tong assembly has a ram assembly for pushing or pulling the upper tong at a tangential location thereof and the ram assembly is retracted or extended to move the tong assembly between an open position, a closed position, and a rotated closed position where the upper tong is rotated relative to the lower tong.