Cold Guns and Air Amplifiers Cool Thermal Spray Coating Process

A Kentucky based thermal spray coating company contacted me recently to solve a problem with excessive heat in their process. This specific application was facing long cool down times after using a plasma spraying process to apply powder feedstock onto a large diameter pipe. The pipe is chucked and turned on a lathe, similar to the photo shown above.

When discussing the application, we first aimed to address the heat and powder dust created by the plasma jet. While some over-spray and dispersion of the feedstock is acceptable, too much can cause variance in the coating finish, leading to quality control failures. Cooling during the application can reduce over-spray and minimize the coating variance. With the intention to provide light cooling and some blow off, we deemed the 5330 High Power Cold Gun Suitable to remove heat and blow away excessive debris.

We then aimed our sights on shortening the cool down time for the pipe following completing of the thermal spray coating. Presently, the cool down time was acceptable, but the application was using (2) open-ended 1” NPT pipes to deliver the compressed air, which is completely unacceptable!

By installing (2) 4″ Super Air Amplifiers on the lathe opposite to the side on which the plasma jet is operating, the end user can replace the 1″ open pipe blow off. A 4″ Super Air Amplifier can provide 2100 SCFM on to the target area, but requires only 29.2 SCFM of compressed air at 80 PSIG. If you compare that to a 1″ open blowoff which can easily require 600 SCFM at 80 PSIG you realize the incredible air savings a Super Air Amplifier can provide. Cool down time improvements are still being recorded and evaluated. When the results are in an update will surely follow this blog.

For cool down and blow off needs in your application, contact and EXAIR Application Engineer.

Lee Evans
Application Engineer

Leave a Reply