Rotor Design Solutions specialize in the method to create variable pitch screw rotors for the Vacuum and Screw Compressor Industries. We have developed a way to quickly and accurately generate 3D models of these parts which may then be loaded directly into CADCAM software. This allows the components to be prototyped using a standard machining center.
The following video shows how the output from Rotor Design Solutions software may be used in combination with Solidworks to create a 3D model. It shows how to create the rotors with a constant pitch, then a variable pitch and finally, a rotor with a section of constant pitch followed by a section of variable pitch. This video follows on from the generation of vacuum screw rotor profiles as shown here.
Variable Pitch components offer clear advantages over the standard uniform pitch components.
The internal compression reduces the pulsation in the gas flow through the screw. This improves the overall efficiency with lower power consumption, quieter operation and a more uniform temperature distribution within the pump, requiring lower cooling water consumption.
Screw Compressor Rotors
This is a relatively new concept made viable by the precise movements a modern machine can make during the cutting process. Variable pitch rotors give better compression characteristics when evaluated against a comparable standard pitch component. They exhibit reduced throttling losses and a smaller sealing line length at the high pressure outlet end.