BBK series explosion-proof transformer fastening bolt fracture how to do?

 The body of explosion-proof distribution box is mostly made of cast aluminum alloy, and the fastening bolt is made of 304 stainless steel. Contact corrosion between different materials is extremely easy to occur, which makes the bolt and the body stick together, leading to the damage of the screw thread of the box, or the bolt fracture when the bolt is removed.

When the explosion - proof distribution box fastening bolts fracture, there are generally two solutions

1. Apply a small amount of butter on the thread of the bolt, which can prevent corrosion and lubricate the bolt, and facilitate the removal of the bolt.

2. Tighten bolts because of corrosion fracture can't take out, drilling tapping again, but because of the enclosure and bolt hardness is different, punching directly, will cause the bit to the material of the soft side offset, will play slant hole. You can use first less than the bit in the center of the screw on the diameter of the bolt hole, with a diameter of drill bit with thread through hole, and then tap tapping it again.