THE PROCESS FOR THICK METAL PUNCHING
CONVENTIONAL METHOD
Metal piercing thicker metals with the current available punch tools requires two steps. • STEP ONE: Pierce the metal with a slightly smaller punch than final specifications. • STEP TWO: Re-punch the hole with a shear punch to achieve design specifications for hole size and maximize wall shear. 2
METAL FLOW • The punch tip makes contact with the metal stock • The metal stock gives way under increased psi from the
punch • As the punch pierces the metal stock it shears the side walls of the hole. • Metal around the hole becomes elastic and tries to close around the punch. 3
THE CHALLENGE
As the punch tool wears, burrs (raised metal) are 5
created. (CONDITIONS CREATE MAINTENANCE COSTS)
DOUBLE PIERCING CHALLENGES
• Misalignment of pieces • Additional time in production cycles • Insufficient shear reduces the quality of the hole
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STEP PUNCH
• Punch tool built with distinct tip diameters • Challenge - Slivers in the die; Slug-ring ejection; Increased tool wear. • Step punches in high volume applications requires increased die maintenance. 7
THE SOLUTION
DUAL TIP TECHNOLOGY 9
Dual Tip Technology (specifically, the Dual Tip Punch, or DTP) is capable of producing one thick-metal hole with one stroke.
DTP WORKS WITH METAL FLOW 10
During the pierce cycle, DTP moves through the metal stock. Metal flows into the annular groove and is cut off by the second cutting surface.
THE RESULTS 11
• • •
Excellent hole dimensions 85+% shear Ability to re-insert the DTP into the hole
THE BENEFITS
EXTEND TOOL LIFE 13
During an extended production cycle, the first cutting surface becomes dull. It is at this point that the second cutting surface, which is still sharp, will correct any imperfections and maintain tolerances.
OTHER BENEFITS 14
•
Eliminates burrs
•
Reduces labor cost
•
Works to harness metal flow
•
Eliminates alignment issues
MEASURABLE RESULTS
SIX SIGMA CAPABLE
• A Six Sigma study of the DTP was conducted by one of our customers. • This is a $7.2 Billion international company. • 24,000 employees around the globe • 409 Stainless Steel • Thickness: 0.062 inch • Hole diameter: 0.774 inch
SIX SIGMA CAPABLE
• Study results indicated outstanding performance during the entire life cycle • The analysis indicated exceptional performance with sustaining hole diameter during the process and minimal burring
PROCESS CAPABILITY OF BURR HEIGHT / INCH M.O.M tools Process Capability of Burr Height / Inches LB
USL
P rocess D ata LB 0 Target * USL 0.006 S ample M ean 0.00145 S ample N 30 S tD ev (Within) 0.000276232 S tD ev (O v erall) 0.000273861
-0.0000 0.0008
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O bserv ed P erformance P P M < LB 0.00 P P M > U S L 0.00 P P M Total 0.00
E xp. Within P erformance P P M < LB * P P M > U S L 0.00 P P M Total 0.00
0.0016 0.0024
0.0032 0.0040 0.0048
0.0056
PROCESS CAPABILITY OF HOLE DIAMETER / INCHES M.O.M. Tools Process Capability of Hole Diameter / Inches LSL
USL
P rocess D ata LS L 0.7677 Target * USL 0.8071 S ample M ean 0.7729 S ample N 30 S tD ev (Within) 0.000335057 S tD ev (O v erall) 0.000332182
0.7696 0.7748 0.7800 0.7852 0.7904 0.7956 0.8008 0.8060
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O bserv ed P erformance P P M < LS L 0.00 P P M > U S L 0.00 P P M Total 0.00
E xp. Within P erformance P P M < LS L 0.00 P P M > U S L 0.00 P P M Total 0.00
RESULTS
• •
• 20
•
No parts fell outside the LSL or USL parameters. The DTP maintained tight tolerances during the entire cycle of the Six Sigma investigation. The DTP increased punch and button life by 536% $4,000 in annual hard savings per press
TAKEAWAYS
The DTP will pierce and shave thicker metals in one stroke. The DTP will eliminate the alignment issue, reduce production time and create a shear that is greater than 85%.
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