Developing a good chip is one of the single most important techniques to master for maximum equipment performance, longest bit life and superior welding results.
All materials machine differently. Tool bit wear will vary greatly depending on tube or pipe material being cut, the schedule or wall thickness, whether or not you are using a coolant, the feed pressure applied, and the actual surface speed of the bit (edge).
Tri Tool has determined that the best (dry cutting) production speed with the least tool bit wear is approximately 300 surface inches per minute (SIM) for carbon steel, 200 SIM for stainless steel and 100 to 150 SIM for titanium, Inconel® and Hastelloy®.
Note: The optimal chip should be between .004 and .007” thick.
A quick and easy way to calculate bit surface speed is to multiply the actual diameter of the pipe by 3 and divide the result into the desired SIM rate. This will give you the RPM that the beveler should be set to run. For example: on 3” carbon steel pipe 3.5” dia. X 3 = 10.5. Divide this into 300, and the result is about 28 RPM.
Your mileage may vary, but this is a good starting point in your development of the best cutting techniques for longest bit life.