Unit Piercing Tool for Round Holes    
This tool is cut to show the parts assembling into the tool. The major parts are the frame, punch and the die button. The sheet to be punched enters into the sheet gap of the tool.

The function of the parts are:

Frame :
A steel body which holds the punch and die inline
Punch :
An interchangeable item which decides the size of the hole in the sheet. Made in HCHC. Allows regrinding
Die Button :
Hardened die, size seleted as per the punch and sheet thickness
Stripping Springs :
Disc springs that pull the punch out of the die
Locating Pin :
A 10 Dia pin for setting dsitance between two frames, and hence between two holes.

Features of the Tool:

No shank needed to grip in press or press brake Automatic alignment of punch and die
Frame of the tool does not carry punching load, and hence will not bend Scrap / slug falls in front of the tool
Punch and die can be changed within 2 minutes Tools are intendd to be used in multiple numbers