By: Cas | Posted on:

Here's a nice video how the double stage rotary screw air-ends of Ingersoll Rand works. In this compressor element, there are two sets of rotary screws: 2 big ones (low pressure stage) and two smaller ones (high pressure stage). It is said that:

They provide increased reliability by reducing the compression ratio required for each stage resulting in lower bearing thrust loads and increased airend life.

Sounds logical, but they probably come with a big price tag, and they have more moving parts, which can be a disadvantage. http://www.youtube.com/watch?v=g8VpnTRWESQ