Stock Strip Layout 7. Design of Press working Tools
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1 7. Design of Press working Tools Nageswara Rao Posinasetti February 6, 2012 1 Since, the components are to be ultimately blanked out of a stock strip, hence , precaution is to be taken while designing the dies for utilizing as much of stock as possible. It is also necessary in progressive dies, to ensure continuous handling of the scrap on the die block, which means that the scrap strip should have sufficient strength. February 6, 2012 2 Stock Strip Layout February 6, 2012 3 Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998. February 6, 2012 4 Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998. February 6, 2012 5 Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998. February 6, 2012 6 Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998. Percentage utilization = 56.5%
Transcript of Stock Strip Layout 7. Design of Press working Tools
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7. Design of Press working Tools
Nageswara Rao Posinasetti
February 6, 20121
Since, the components are to be ultimately blanked out of a stock strip, hence , precaution is to be taken while designing the dies for utilizing as much of stock as possible.
It is also necessary in progressive dies, to ensure continuous handling of the scrap on the die block, which means that the scrap strip should have sufficient strength.
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Stock Strip Layout
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
Percentage utilization = 56.5%
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
Percentage utilization = 56.5%
Percentage utilization = 73.5%
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
Percentage utilization = 56.5%
Percentage utilization = 76%
Percentage utilization = 73.5%
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Fig. From P. N. Rao, Manufacturing Technology, Tata McGraw Hill, 1998.
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Step 1: Decide the tentative sequence of operations. Step 2: Layout the stock strip, preferably using at least three
part templates. Step 3: Establish centre line of pressure. Step 4: Establish location of pilot hole punches. Step 5: Decide on the punches to be used and their placement
from the strip layout. Step 6: Make preliminary layout of die block. Step 7: Locate and design any finger, swing type, or automatic
stops.
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Sheet Metal Die Design Procedure
Step 8: Selection of best die set, total design considered.
Step 9: Make adequate provisions for scrap disposal. Step 10: Decide best keying methods. Step 11: Check for good dowelling practice. Step 12: Make punch plate sufficiently thick to
support all punches adequately. Step 13: Decide upon stripper and shedders and
requirements.
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Sheet Metal Die Design Procedure
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Step 1: Decide the tentative sequence of operations.
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Step 2: Layout the stock strip, preferably using at least three part templates.
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Step 3: Establish centre line of pressure.
Shearing should be symmetrical about the axis of the ram.
This ensures no side thrust. To do this, the point on the die block is to be found
out, through which the resultant of all the shearing forces is acting and this is coincided with the ram axis.
This point is called the centre line of pressure.
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(c) TMH New Delhi, Manufacturing Technology Vol 1, Foundry, Forming and
Welding by P N Rao38
Centre Line of Pressure
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(c) TMH New Delhi, Manufacturing Technology Vol 1, Foundry, Forming and
Welding by P N Rao39 February 6, 201240
Step 4: Establish location of pilot hole punches.
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Step 5: Decide on the punches to be used and their placement from the strip layout.
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Step 6: Make preliminary layout of die block.
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Step 7: Locate and design any finger, swing type, or automatic stops.
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