This document discusses common defects that can occur in the deep drawing process and their remedies. It describes defects such as flange wrinkles, step rings, draw marks, orange peel, scratches, fractured flanges and bottoms, corner fractures, miss strikes, and directional earing. For each defect, it provides details on what causes the defect and potential remedies, such as increasing the blank holder force, using a draw bead, ensuring proper lubrication and die surface finish, working within material limits, and providing sufficient blank holder force. The overall document serves as a guide for identifying and addressing issues that may arise during the deep drawing manufacturing process.

1. Defects In Deep Drawing And Their Remedies
Submitted By:
Shivam pandy
REG. No. PGWLF/1750161
Mechanical Deptt
Sub Name: Seminar
Sub Code: PCME 825

2. Table Of Content
 Introduction to Deep Drawing Process
 Common Defects And Their Remedies
 Flange Wrinkle And Wall Wrinkles
 Step Rings
 Draw Marks
 Orange peel
 Scratches
 Fractured Flange And bottom
 Corner Fracture
 Miss Strike
 Directional Earing
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3. Deep Drawing
It is process of converting circular or spherical blank into cup shape
component.
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4. Flange Wrinkle And Wall Wrinkles
 It occurs when compressive stresses (Hoop
Stress) in circumferential direction reaches
critical point of instability.
 It occurs where work piece is unsupported or the
blank holding force is in sufficient.
Remedies:
• Increase blank holder force
• Using a Draw Bead
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5. Step Ring
 Its formed during Redrawing when the Redrawing is performed
near the LDR value, Step Rings appears on the drawn cup.
Remedies:
 Redrawing operation must be performed at lower value of draw
ratio.
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6. Draw Marks
 It occurs due to the improper finish of the die surface Draw Marks
appears on the draw cup.
 Surface finish of die gets deteriorates due to improper lubrication
between blank and die.
Remedies:
 Proper lubrication
 Good surface finish
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7. Orange Peel
 It occurs due to coarse grain structure of the drawn material.
Remedies:
 Grain structure should be refined before deep drawing.
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8. Scratches
 Heavy scratches over the drawn cup may appear due to appearance
of yield point phenomenon in the material.
Remedies:
 Steel material must be consumed within the strain aging time of
material.
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9. Fracture Flange And Bottom
 When the sheet metal is subjected to strains exceeding the safe strain
limits of the material.
 For ductile sheets this fracture usually occurs near the punch corner.
 It happens when draw ratio exceeds the LDR or holding force is
more then required.
Remedies:
 Sufficient holding force.
 Working under LDR ratio.
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10. Corner Fracture
 Same as Flange and Bottom Fracture
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11. Miss Strike
 Due to non symmetric placement of blank over die, this defect Miss
Strike.
Remedies:
 Proper alignment of workpiece
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12. Earing
 Anisotropic sheets result in a drawn cup with uneven top edges.
(Planer anisotropy of blank material).
Remedies:
 Ironing is performed to make the thickness of drawn cup uniform.
 But excessive Ironing produces burnishing.
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13. References:
 Dr. Swadesh kumar singh’s book of Production Engineering.
 R.K Jain’s book of Production Technology.
 Kalpak Jain’s book on Manufacturing Engineering and Technology
 Google.
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