Common sense of screw application

Apr 14,2022 / BY DEVELOPERS

1. First remove the sludge on the surface of the broken head of the broken screw, use the center gun to kill the center gun of the section, and then use an electric drill to install a drill bit with a diameter of 6-8 mm to drill the hole in the center of the section, pay attention to the hole must be drilled through. After the hole is drilled through, remove the small drill bit and replace it with a drill bit with a diameter of 16 mm, and continue to expand and drill through the hole of the broken bolt.

2. Take a welding rod with a diameter of less than 3.2 mm and use a medium and small current to carry out surfacing welding from the inside to the outside in the hole of the broken bolt. Take half of the entire length of the broken bolt. When starting the surfacing welding, the arc should not be too long. In order to avoid burning through the outer wall of the broken bolt, surfacing to the upper end face of the broken bolt, and then continue surfacing to weld a cylinder with a diameter of 14-16 mm and a height of 8-10 mm.

3. After the surfacing is finished, hammer the end face with a hand hammer to cause the broken bolt to vibrate along its axis. Due to the heat generated by the previous arc and the subsequent cooling plus the vibration at this time, the broken bolt and the thread of the body will be loose in between.

4. Carefully observe, when it is found that a small amount of rust leaks from the fracture after the knock, take the M18 nut and put it on the surfacing column head and weld the two together.

5. After welding, use a Torx wrench to cover the nut while it is still hot, and twist it back and forth. You can also tap the end face of the nut with a small hand hammer while twisting back and forth, so that the broken bolt can be taken out.

6. After taking out the broken bolt, use a suitable tap to process the thread in the frame to remove rust and other debris in the hole.

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