Exhaust Tubes

Exhaust tubes (foot valves, blow tubes) are an important part of the drill bit. Expensive downtime can be reduced by having some on hand. Nothing like having a little piece of plastic ruin your day. A lot of bit manufacturers have their own specifications for fitting the exhaust tube into their bit, but many have standardized on QL, IR, and Mission style tubes. It is always best if you know the manufacturer of the bit so you can get the correct tube. We need to know the ID and depth to shoulder of the hole in the bit.

To remove a broken exhaust tube you can either cut it with a reciprocating saw and pry it out or you can burn it out with an acytelene torch or blowtorch. Lay the bit on its side, get the tube burning, and then let it burn itself out. Obviously if you are using this method, fire prevention measures must be taken.