Piercing tool consists
1. Top plate
2. Bottom plate
3. Punch
4. Die
5. Stripper
6. Punch holder
7. Thrust plate
8. Nest pins
9. Guide pillar
10.Guide bushes
11.Shank
Top Plate
This is the plate on which the punch holder is fixed.The shank and the guide bushes are fitted on this plate.The plate absorbs the shock resulting due to the cutting action.
Bottom plate
This is the base of the tool.The die and pillars are fixed on this plate.The openings for the slugs is made in this plate.Bottom plate also absorbs the shocks from the die plate during the cutting operation.
Punch and Die
They are the cutting elements of a piercing tool.They are made of high carbon high chromium steel and are hardened and tempered to 58-62 HRC.
Stripper
In a piercing tool travelling atripper is used to facilitate easy loading of unit stock.Stripper strips the component of the punch after the piercing is done.It also holds the component flat during the operation.The punches are guided through the strippers.
Punch holder
Punch is fitted to the punch holder with a light pressfit(H7/m6).It is made of mild steel.
Thrust plate
While performing the cutting,the punch will exert an upward thrust.So the punch should be backed up by a hardened(45-50 HRC) plate to avoid the digging on the soft top plate.For this purpose the thrust plate is used.
Nest pins
The blanked components is located by the nest pins before piercing.
Guide pillars and bushes
They are used to achieve a well guided movement of the moving part with respect to the fixed part.
Shank
Shank connects the top half of the tool to the press ram.It is screwed on to the top plate.
Screws
It is the main fastening member which holds the plates together.The number of screws and its size is decided depending upon the size of the tol and load acting on the tool.
dowels
Dowels are the main locating member.They locate the plates accurately in position.