Development and application of force release device for the sticking of manual pipe tapping machine

When a manual pipe tapping machine is used for the tapping during the emergency rescue of oil and gas pipelines, sticking occurs and leads to the reverse rotation of electrical motor. To solve this problem, a force release device for the sticking of manual pipe tapping machine was mechanically designed in this paper. This device is composed of drive mechanism, damping mechanism and differential mechanism. When the pipe tapping machine is in normal operation, the torque of electrical motor is transferred to the tapping bit through the drive mechanism. In the case of sticking while the tapping bit is cutting the pipe wall, the torque of electrical motor is transferred to the damping mechanism through drive mechanism and differential mechanism to overcome the rotation work of damping mechanism and release the torque. It is shown from tapping tests that this device can prevent effectively the personal injury caused by the reverse rotation of manual pipe tapping machine, improve the safety of pipeline rescue operation and protect the personal safety of operating personnel.