The sharp boundary punching cylinder is mainly due to the serious shortage of lubricating oil, resulting in poor lubrication, resulting in severe friction temperature between the cylinder and the piston and between the connecting rod. The temperature rises, but the heat dissipation is not good enough to play a cooling role, resulting in a small lubrication gap, resulting in the piston, cylinder, connecting rod between the lock. As the strong inertial force continues to make it run, it is easy to pull the cylinder stuck, causing serious impact damage to the cylinder.