how to design A screw Compressor

please help to design these part

1 Answer

I don't know about NX, but I'd assume the basic steps are the same between most CAD programs.

I'd call this "close enough" to show the basic shape, but I would not suggest machining it and trying it an expensive compressor. Let's blame any defects on the quality of the photo :)

Two images attached, one shows the steps taken to build it.
One rendering
Step file
SW file is 2017