Concept explainers
The rolling force and the power requirement for single pass.
The rolling force and the power requirement for double pass.
Answer to Problem 6.120P
Rolling force is
Rolling force is
Explanation of Solution
Given:
The initial height is
The final height is
The radius of the rollers is
The coefficient of friction is
The width of the sheet is
Velocity of the roll surface is
Formula used:
The expression for change in height for single pass is given as,
The expression for change in height for double pass is given as,
The expression for contact length for single passis given as,
The expression for contact length is given as,
The expression for rolling force is given as,
The rolling force for double pass can be given as,
Here,
The expression for roll separatingstressis given as,
Here, strength coefficient is
The expression for the strain is given as,
The expression for the angular velocity is given as,
The expression for the arm length is given as,
The expression for the arm length in double pass is given as,
The expression for the torque is given as,
The expression for the torque for double pass is given as,
The expression for the power is given as,
The expression for the power for double pass is given as,
Calculation:
The change in height can be calculated as,
The contact length can be calculated as,
The strain can be calculated as,
The roll separating stress can be calculated as,
Refer to table 2.2“Typical values of strength coefficient
The force for single pass can be calculated as,
The angular velocity can be calculated as,
The arm length can be calculated as,
The torque can be calculated as,
The power can be calculated as,
The change in height for double pass can be calculated as,
The contact length for double pass can be given as,
The arm length for the double pass can be calculated as,
The rolling force for double pass can be given as,
The torque for the double pass can be given as,
The power required for double pass can be given as,
Conclusion:
Therefore, rolling force is
Therefore, rolling force is
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Chapter 6 Solutions
Manufacturing Processes for Engineering Materials (6th Edition)
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