Tricone drill bits

**Alastair** · 11-09-2015, 08:15 AM

I have 70 tons of tricone drill bits. I am looking for a better way to extract the tungsten than gas cutting torch method.

**t00nces2** · 11-09-2015, 09:19 AM

Isn't tungsten dangerous to work with? I was under the impression that that grinding and melting tungsten can kill you. I hope you know what you are doing.

On the other hand, it is only 70 tons, probably not enough to worry about.

**DAVECCT** · 11-11-2015, 04:42 PM

cutting torch method is the best way. I'll PM you the price we are paying for brazed carbide

**armygreywolf** · 11-11-2015, 10:29 PM

Heat treatment oven or smelting furnace or kiln for pottery. You have to be able to get it to 1800 or so anyways. In the past I was able to use stainless steel baskets and a pottery kiln. Tricone bits are super heavy but if you weld a chain link to the shank and put it face down in a larger kiln you can get it hot enough to get the carbide out.

I'll share my method exactly for you.

I first weld a heavy link or loop to the bit shank. then I take the bit and use a cherry picker to put it in the kiln, being very very careful to set the 400(sometimes alot more than that) lb bit on firebrick not the refractory material. some were so heavy the kiln had a hard time supporting the weight so I cut a small glory hole to feed the picker chain through the lid and then the bit would be supported by the chain through the hole. Pack the hole with ceramic insulation if you need to.

Next the bit is heated for 6 to 8 hours, or until the 1800 degree heat treatment pencil burned off. (usually at least 6 hours). At this point its time to glove up and put a face shield on.

Take the lid off (very very carefully, when hot the refractory is super brittle. Pick the bit up, move it somewhere where its safe to beat on it with a sledge hammer. Now you will want to hit it on the edges and the shank not the face. The carbide will fall out. Any that dont come out can be quenched with a water (use a sponge or something like it) as soon as they cool enough they contract and fall out (carbide does not expand at nearly the rate of steel so it may still require gouging if their stuck). When your done a 400 lb bit yields about 35 lbs of carbide, dont bother to extract carbide from anything less than an 8 inch tricore it is a huge waste of time and you end up with only a few lbs. I know this stuff because I used to live in oil country and it was one of the things I did for money on the weekends.