Method for quickly drilling hole in steel pipe with water and connecting branch pipe to steel pipe

The invention discloses a method for quickly drilling a hole in a steel pipe with water and connecting a branch pipe to the steel pipe. The method aims to overcome the defects that in the prior art, a hole cannot be drilled in a steel pipe with a large amount of water, then a branch steel pipe cannot be connected to the steel pipe, waiting time is long and water supply to other branch pipes is affected if hole drilling and butt joint are conducted after the water is discharged, and waste is caused when the water is discharged. The method comprises the steps of manufacturing a hollow water drill bit, welding a water drill bit locating pipe at the position, where the hole needs to be drilled, in the main steel pipe, welding the branching steel pipe at the position, outside the locating pipe, of the main steel pipe concentrically, installing a ball valve on the branch steel pipe, opening the ball valve, drilling the hole between the branch steel pipe and the locating pipe through the water drill bit, taking out the cut portion of the locating pipe, closing the ball valve and connecting the branch pipe. According to the method, the water inside the main steel pipe does not need to be discharged, the hole is drilled in the pipe wall without electric welding or gas welding, time used for connecting the branch steel pipe is saved by four to five hours compared with that spent in the prior art, the working efficiency is high, welding quality can be ensured, water waste is reduced, and water usage of other places is not affected in the process of connecting the branch pipe.