Shutter door springs can generally be divided into two types, one is divided into two types of torsion springs and steel garlands, of which torsion springs are the most widely used, and the installation of torsion springs requires grasping the spring shell of the torsion spring and facing the direction of people. Be sure to grasp upwards, and then use the right hand to remove the screw fixed on the door with a wrench. After two hands slowly loosen the spring until there is no resistance, each is like this, and then roll the two sides of the manual beam. Remove the screw, then take it down and put it on the ground. Then remove the spring screw of the manual rolling door. Then the new one is put on the removed spring and the screw is fixed. Of course, the roll is also installed in the same way as it is now. Starting to tighten the spring is also the most critical operation. After tightening to the desired resistance, the screw is damaged and replaced.