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Sample Die Design Standards
Statement
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It is the Tool Source's responsibility to insure that all tools are in
compliance to the latest OSHA standards. The following design
standards do not supercede OSHA requirements. By accepting a P.O.
the tool source is responsible for recognizing any discrepancies
between OSHA standards and our guidlines, and to notify our responsible
personnel.
Consideration of the method of feeding, removing parts from the die and
scrap shedding provision is of the utmost importance. Safety,
ergonomics and efficiency must be given priority during tool design and
build.
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Safety Specifications
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1.
There will be provisions for clearance for part handling, safe scrap
removal, and safe part ejection.
2. Manual handling of
scrap will not be permitted without written authorization.
Shedding trimming of scrap should be away from operator.
3. Die lubrication
requirements and their safe applications must be approved upon die
design review.
4. Clearance for slugs
will be designed into the die as well as a method to remove them from
the die. Example: slug shakers
5. Whenever possible, dies
will be designed to permit visual inspection by the operator for scrap
and slug removal.
6. Guide pins should be long
enough to remain in the ball cage during the entire stroke whenever
possible.
7. All exposed springs
must be contained for safety in case of failure. It is
recommended to use spring guards with windows to an operator can see if
a spring is broken.
8. All auxiliary devices
must be located to eliminate the possibility of being damaged during
die setting operation.
9. All dies must have a designated flat area to support safety
blocks for repair while the die is in the press.
10. Escaping air from
blow-off system are to be vented away from the operator. Air
blow-offs are to be used as a last resort to part ejection and must be
approved during die design review.
11. Provision shall be
made in both the upper and lower shoe for securely mounting the die to
the bolster and slide incorporating JIC standards. Please see
Figure 1.
12. All secondary operation dies will be provided with a means of
stripping parts from the punch and out of the die with a means of
automatic ejection, except with written authorization.
13. All progressive dies will be designed and built so that parts
eject at each stroke. Chutes are to be used when parts fall free
at die level. Chutes are to be designed as part of the die where
practical.
14. Use a caution tag near nitrogen gage stamped "Not to exceed
XXX P.S.I."
15. Nitrogen control panel will be accessible in press, for
adjustment and fill, at the front of the die.
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Die Component Requirements
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1.
Air vents will be provided at all guide bushings.
2. All standard punches are to be heavy duty (M2) high speed
steel ball lock ejector punches.
3. All standard buttons are to be heavy duty (M2) high speed
steel, headless, press fit. Unheaded design buttons for other
than round, should have locating flats to be keyed from the die surface.
4. Strippers are to be of three types. Nitrogen strippers
are preferred. They will be used wherever heavy stripping or
positive holding force is required. Self contained nitrogen gas
springs are acceptable, manifold systems are preferred. Spring
strippers should only be used in simple stripping operations.
5. All manufactured punch details will have an ejector mechanism
whenever possible. All new tooling will be free of welds.
Sections welded during development must be replaced with new sections.
6. Tooling will be designed so that part removal does not mix with
scrap or slugs.
7. All large puunch and die details should incorporate shear or
staggered to reduce tonnage requirements and snap-thru shock.
Consideration must be given for ease of maintenance and flatness
requirments.
8. Symetrical parts are to be stamped with part number, unless
otherwise specified. Symetrical parts should be further
identified as "right' and "left".
9. Jackscrew holes will be used in die sections and retainers, and will
be removable in the press.
10. All sections will be mounted with tapped holes in die set or
mounting plates.
11. Retainers that are used to locate trim punches and sections must be
hardened and ground.
12. 90 degree wipe steels and inside forms will be made with inserts if
practical. All form wipe punches are to be designed to set radius
and to be heeled before start of form.
13. A shedder pin will be installed in the stripper at cut off to
prevent the part from sticking to the pad.
14. Stripper pads are to have minimum 5/8 handling holes for
removal with eye bolts if size warrants.
15. All die sets should have 2 handling holes on front and rear edges
and on top and bottom. 1"- 8 for dies up to 10,000 lbs. Use
1 1/4-7 tap for die up to 20,000 lbs, and use 1 1/2-6 for dies over
20,000 lbs.
16. All pierce dies will have adequate means for slug ejection.
This must be approved before die build.
17. Stop blocks will be mounted over parallels. Minimum of 2"
between stop blocks and guide bushings. Stop blocks should not be
in the way of part discharge, or first stop when used.
18. Slug ejectors will be provided on all notch and pierce
punches.
19. All pierce retainers for material over .062 will have
hardened (RH'C' 50-54) backup plates with shims provided for sharpening.
20. Positive strippers will be screwed and doweled separate from die
sections.
21. Screws that are subject to vibration and abuse will be nylock or
equivalent to prevent them from coming loose.
22. Die springs will not be compressed more than manufacturers
specifications for average spring life.
23. All spring pockets in die shoe will have drain holes.
24. Notching, forming and cutoff sections will be properly heeled and
keyed.
25. Scrap cutters must be incorporated.
26. A slides, pad keepers, wear plates, and heeling surfaces will be
provvided with grooves for lubrication and necessary means of
lubricating those areas.
27. On cam dies or cam stations, spring cages or guards will be
provided to contain springs in case of failure.
28. Form steels are to be supported over parallels.
29. 1/2" diameter screws are preferred for retaining die
sections. Blind dowel holes will not be used.
30. A minimum of 1.5" x 3" stop blocks will be provided at two places,
if possible, with a .050" deep by 1/2" wide lead slot. Stop
blocks should be clear by .010" with die fully loaded at bottom of
press stroke.
31. Pad balance blocks will be used when possible.
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Die Set Requirements
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1. Precision ball bearing die
sets are to be used.
2. On progressive dies, parts must either be blanked through the shoe
or cut off on the end of the shoe. Feed progression should not be
used as a means to eject a part. The end of the die shoe should
be angled or have an ejector to aide the removal of the part.
3. Clamping. . . . . see Figure 1.
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Progressive and Blanking Dies
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1. Pitch notches are to be
incorporated for stock advance. A pitch notch on both sides of
strip is preferred.
2. All dies to have a start line on bottom sections, visible from front
side of die.
3. Progressive dies will be provided with chutes to assist in leading
material into stock guides and die.
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Parallels
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1. All clamping parallels must
be a minimum of 2" wide with a 7/8" bolt slot thru clamping foot.
2. If parallels are used on top die shoe, they must be bolted up
through top shoe into parallels. Bolts for paralles are to be
countersunk into die set. Bottom parallels must be bolted down
through shoe into parallels.
3. Parallels not intended for clamping may be a minimum of 1.25" thick
and fastened with 1/2" bolts.
4. Bottom parallels must have minimum 6" space for fork lift
forks. If this is not possible, lifting lugs must be provided.
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Tool Identification
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1. Information to be stamped on
punch and die:
a. Part Number (on die and punch)
b. Stock thickness and progression
c. Shut height
d. Top die shoe weight
e. Total die weight
f. Nitrogen working pressure
g. Customer job number or asset number
2. All the die steels will be stamped with detail number, type of
steel, and hardness on a nonfunctional surface and located in an area
that will not be ground away.
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