Stainless steel threaded bolts can often seize in a hole and become very difficult to remove. In fact, a seized bolt often results in a stripped bolt head, which increases the difficulty of removing the bolt. There are several methods you can try to get the seized bolt out.
Things You'll Need
5-point box-ended wrench
Drill bit set
Reverse threaded tap or bolt extractor
Spray the bolt with penetrating oil and wait two to four hours for the oil to penetrate the threads on the stainless steel bolt.
Place a 5-point box-end wrench onto the bolt head. Do not use a socket because a socket makes it harder to apply direct pressure to the bolt head. A 5-point wrench ensures each side of the bolt head has equal pressure on it.
Turn the wrench counterclockwise to remove the bolt. If the bolt still does not move, remove the wrench and go to the next step.
Heat the bolt head with a blowtorch for two to five minutes to heat the bolt and surrounding surface area. This forces everything to expand, which loosens the threads in the hole. Attempt to remove the bolt head with the wrench. If the bolt does not come out, move to the next step.
Place a breaker bar onto the wrench. A breaker bar is a metal pipe that slips over the end of the wrench. This increases the amount of torque you can place on the bolt.
Heat the bolt again and place the wrench and breaker bar onto the bolt head. Attempt to remove the bolt with the breaker bar. At this point, the bolt should come loose and the head with either strip or break off.
Drill a hole down through the center of the bolt. Keep the drill bit vertical at all times. Use a drill bit approximately half the size of the bolt's diameter.
Place a reverse threaded tap into the hole or a bolt extractor and then turn the threaded tap clockwise. This turns the tap into the hole. When it grips, it will turn the bolt counterclockwise and remove it from the hole.