Special tool for aligning large flanges

The utility model provides a special tool for aligning a large flange, which comprises a fixing device and an adjusting device, the fixing device comprises a pair of halves matched with an aligning pipeline, the adjusting device comprises four adjusting arms, the adjusting arms are arranged on the outer side of a reference flange, the halves are arranged on the outer sides of the adjusting arms, and the halves are arranged on the outer sides of the adjusting arms. A fixed bolt is arranged at the upper end of the adjusting arm, an adjustable bolt is arranged in the middle of the adjusting arm, a measuring dial indicator is arranged at the position, relative to the reference flange, of the adjusting arm, and a jack is arranged at the position, relative to the counterpart flange, of the adjusting arm. Connecting holes are formed in the side face of the half at 30 degrees, 60 degrees, 90 degrees, 120 degrees and 150 degrees. And the adjustable bolts are inserted into the connecting holes. According to the flange