FAQ –  Questions and answers regarding the Punch Tap technology

What is Punch Tap

• It is a new technology for the very fast production of internal threads.
• It is also called “helical thread forming”

What does the name Punch Tap mean?

• The name Punch Tap is derived from the punch in professional boxing and characterizes the sudden plunge of the tool and the fast retraction.

How does a Punch Tap work?

• Information concerning the functionality can be found in the product video or in the product brochure.

Who invented the new production technology and who developed the Punch Tap?

• AUDI and EMUGE are the inventors and developers of the Punch Tap technology

What are the advantages of the Punch Tap?

• Time savings at the production of internal threads.
• Energy savings
• Only one storage position is needed in the tool magazine
• The thread flank is produced in a cold-forming process

Is the Punch Tap available only from EMUGE?

• Yes, only from EMUGE. The process and the tool are patented.

Who can be delivered with Punch Tap?

• Everybody

How does the time advantage of the Punch Tap compare to a cold-forming tap in a synchronous machining cycle?

• The time advantage of Punch Tap is up to 75%

Which materials can a Punch Tap be used for?

• In particular aluminum cast or wrought alloys and similar light metals that are suitable for cold forming.

Which types of threads are possible with the Punch Tap?

• Currently metric systems
• Other sharp threads (UNC, UNF, Self-Lock…) are possible

Which dimensions are possible with the Punch Tap?

• Dimensions M3; M4; M5; M6; M7; M8; M10 are available.
• Smaller sizes are possible

How long is the difference between pre-drill hole and usable thread length at Punch Tap?

• Form E: 3 pitches (=2 pitches for Punching teeth and 1 pitch safety distance to the bottom of the pre drilled hole)
• Form F: 2 pitches (=1 pitches for Punching teeth and 1 pitch safety distance to the bottom of the pre drilled hole)

Will cold formed threads or cut threads be produced by Punch Tap?

• Punch Tap produces cold formed threads.

Which tolerances can a Punch Tap achieve?

• Currently 6H
• Other tolerances (6G, 7G…) are possible

Which depths of thread are suitable for a Punch Tap?

• Up to 3xD has been tested

On which machines can a Punch Tap be used?

• On CNC machine tools with a sync control system with available Punch Tap cycle

How will the Punch Tap cycle be implemented?

• The implementation of the Punch Tap cycle will be done by machine tool builder or control unit supplier.

Is the Punch Tap already in use in series production?

• The mass production at the AUDI plant in Györ was in the beginning of 2016

Can a Punch Tap be reground?

• no

Which design does the Punch Tap have?

• Shank in h6 tolerance with lateral inclined clamping flat
• Dimensions according to EMUGE-standard, depending on application

Which type of tool holder does the Punch Tap require?

• A special EMUGE Punch Tap (PT Synchro) holder is used
• Due to the specific process a rigid clamping is necessary
• The jerky tension- and compression forces and the torque, must be transferred.
• Conventional clamping systems are not suitable for these types of stress.

What type of holes can the Punch Tap be used for?

• There is one basic tool for blind holes and through-holes

What is the suitable pre-drill diameter respectively tolerance?

• Analogous to conventional thread forming
• It might be necessary to adjust pre-drill diameter and tolerance.
• Chart for recommended pre-drill diameter: see product brochure

How can you gauge the produced thread?

• As usual, with conventional gauges according to DIN ISO 1502.
• The minor diameter with a smooth Go/No-Go plug gauge with tolerance -7H
• The thread is gauged with Go/No-Go thread plug gauge with tolerance -6H

When will chips occur in the process?

• When punching the two helical grooves (immersion of the tool into the workpiece)
• During retraction of the tool. Some material, that entered the helical groove during thread forming, will be pulled out.

What does Punch Tap cost?

• Please ask for an offer

Is a questionnaire available?

• A technical questionnaire is available.