Imagine a situation when, in the process of repairing equipment, you need to disassemble a unit, but you cannot do this, because one of the mounting bolts did not have a cap. The situation is well known, do not despair. There are several fairly simple ways to solve this problem.
Instructions
Step 1
If, for example, the point of the bolt fracture is located in the immediate vicinity of the surface of the part, then it is worth resorting to the help of a sharp core. Position it at an angle to the edge of the bolt and, with a light tap, try to rotate it counterclockwise (for a right-handed bolt). Sometimes this is enough.
Step 2
Another option can be realized with the help of a grinder, provided that the upper part of the "decapitated" bolt protrudes at least a little above the surface of the part. Cut a slot in it for a screwdriver using a thin cutting wheel of 0, 8-1, 00 mm in size and you can start removing the bolt.
Step 3
The next, perhaps the most reliable, method is with a left-hand thread tap. First, make a punch mark in the center of the bolt and drill a hole 2-3 mm smaller than the bolt in diameter and 10-15 mm deep. Then start screwing the tap into the hole until the resistance of its rotation exceeds the friction force of the bolt thread, after which it starts to turn out.
Step 4
In the absence of a tap, you can try to remove the bolt with a screwdriver, the edges of which are sharpened on a taper so that it fits into the hole. For a more secure fixation in the hole on the screwdriver, hit it slightly with a hammer several times.
Step 5
A right-hand tap can also be used to remove a broken bolt. As soon as the bolt begins to go inward, begin to unscrew it. The next method involves the use of welding, but only under three conditions: a) if the bolt has a diameter of more than 10-12 mm; b) the welder is highly qualified; c) the fracture line is close to the surface (in this case, you can try to weld a piece to the broken bolt metal and unscrew the bolt with it).
Step 6
In the most extreme case, when all of the above methods could not be implemented, it remains to drill the bolt with a drill, the diameter of which corresponds to or is close to the diameter of the bolt. After that, a hole should be drilled for a new larger thread. For example, for M8 threads, make M10 or M12.
