You can easily remove broken bolts, studs, and pins with an Electro Arc metal disintegrator. Use your Electro Arc metal disintegrator for dowel pin removal. For example, to remove a 1/2″ x 2″ stainless steel dowel pin with our 2-DVQT with 20 KVA power supply, you will use a .250 molybdenum electrode. To do this, disintegrate a 1/4″ hole from where the threads end to the bottom of the pin. Using a 3/” tap and tap handle, twist the dowel out of the hole. You can avoid destroying the 3/8″ threads using a 1/4″ heat shrink tube over the molybdenum electrode. If the dowel pins do not have threads, you can use the same method except you will use a sporal easy out to get the pin out of the hole.
In our example, we used the heat setting 5 on the metal disintegrator and the disintegration went 2″ deep. Disintegration time was 5 minutes and 24 seconds to remove this broken dowel pin.
When you need to remove a broken screw or bolt, have two options, you can disintegrate a more shallow hole to create a slot or grove for a screwdriver or breaker bar. If you cannot turn the screw or bolt out, the quickest method is to disintegrate a screwdriver slot, hex, or square in the end of a bolt and turn it out.
If it can be turned out:
Screwdriver slot– Collapse an appropriate size copper tubing electrode to format blade cutting tip in a vice. Caution should be taken so that the flushing hole in the center of the electrode is not closed. Disintegrate a screwdriver slot in the end of the screw or bolt and turn it out.
Hex for Allen wrench – Tip electrode with appropriate brass copper or graphite size hex electrode, disintegrate the socket and turn out.
Square socket for rachet or air wrench – Tip electrode with appropriate size square made of brass, copper, or graphite. Disintegrate socket and turn it out.
If it cannot be turned out:
Badly galled or rusted screws, studs, bolts, or pins that cannot be turned out can be easily removed with an appropriate size electrode, and the threads are saved – even with a broken easy-out!
Screws, bolts, studs, and pins to 3/4″diameter:
To remove the broken screw, bolt, stud or pin, you first need to determine the tap drill size of the hole. Use an electrode .020″ under the tap drill size. With the proper size electrode, you can cut at 30 to 50 amps and use the recommended cutting power selection recommended on Electro Arc’s selection chart (AC, DC, or Bolt Eater). This will achieve a .008″ per side over-cut and leave a .002″ shell standing in the female threads in the hole. After you complete the cut, you can remove the male threads from the female threads with a magnetic pick set. With proper alignment, the male threads will come out looking like a spring.