Standard |
MCA 223 – Die Design II
Provides a continuation of MCA 220. More advanced theory and projects will be presented. Topics include: related formulas, calculation of bends, draw die calculation, fasteners, spring selection, and safety.
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Competency Areas |
Hours
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Related Formulas |
Class |
5 |
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Bends Calculations |
D. Lab |
2 |
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Draw Die Calculations |
P. Lab/O.B.I. |
3 |
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Fasteners |
Credit |
7 |
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Spring Selection |
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Safety |
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Prerequisite: |
MCA 221 |
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Corequisite: |
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Course Guide |
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Competency |
After completing this
section, the student will: |
Hours |
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Class |
D.Lab |
P.Lab/
O.B.I. |
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RELATED FORMULAS |
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Area and strength |
Define tensile strength and the formula for finding cross-sectional areas of common shaped material. |
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Pressure |
Calculate pressure required to punch round holes in various materials, stripping pressures, blanking pressures, and find scrap allowances. |
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Drawing forces |
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Clamping force |
Determine the clamping force of screws. |
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Bending force |
Find the bending force when given ultimate tensile strength, width of metal bend, thickness of sheet, and span. |
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BENDS CALCULATIONS
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Theory |
Explain how thickness of stock and degree of bend affects the length of the stock required in a part. |
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Use the bend formula to find the length of the part measured from the end of a leg to the beginning of the bend, inside measurements of legs, for angles greater or less than 90 degrees and measurements for multiple bends. |
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Explain "spring-back" and the formula for the spring back factor "K." |
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Use tables for approximate length of bend allowances. |
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Application |
Lay out, bend, and measure workpieces with bend allowances calculated and compare true size of finished part to the required size. |
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DRAW DIE CALCULATIONS
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Design factors |
List three design factors in design of draw dies. |
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Define clearance, angular clearance, shell drawing, shut height, and classes of dies. |
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Explain how depth and diameter reductions of drawn shells are determined for sheet steel blanks with various numbers of draw operations. |
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Calculations |
Determine clearances, angular clearances for different materials, and working pressures. |
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Calculate the blank size of various shapes such as cone, square, cylindrical shells, etc., and reduction rates. |
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Explain how the strain factor Ec can be used to measure thickening of a draw blank. |
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Demonstrate the principle measures of ironing, including shell-wall thickness, strain factor, height of shell wall after ironing length of the width. |
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Explain the relationship of length to width and the formula for the draw depth of rectangular boxes. |
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FASTENERS
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Explain the use of pins, threaded fasteners, bowls, rivets, socket set screws, press fitted fasteners, folding, staking, curling, hemming, seaming, or wiring. |
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SPRING SELECTION
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Define deflection, limits of springs and central classification of springs. |
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Explain the requirements of spring location and mounting to match available space and service requirements. |
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SAFETY |
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Suggested Resources |
American Society of
Tool and Manufacturing Engineers Staff. (Ed.). (1965). ASTME die design handbook. New York: McGraw-Hill.
Jones, F. D. (1951). Die design and diemaking
practice. New York: Industrial Press.
Keyes, K. A. (1982). Innovation in die design. Dearborn, MI:
Society of Manufacturing Engineers.
Paquin, J. R. (1987). Die design fundamentals. New York: Industrial Press.
Paquin, J. R., & Crowley, R. E. (1987). Die design fundamentals. New York:
Industrial Press.
Smith, D. (1990). Die design handbook. Dearborn, MI:
Society of Manufacturing Engineers.
Society of
Manufacturing Engineers Staff. (Ed.). (1978). Manual of instruction for die design. Ann Arbor, MI: Prakken.
Society of
Manufacturing Engineers Staff. (Ed.). (1971). Die design and construction. Ann Arbor, MI: Prakken.