Q1\ a) The operation of drilling is to be done with a 25.4 mm ( diameter) twist drill in a brass workpiece. The hole is a blind-hole with the point angle = 118°, and a depth of 50 mm. The speed of 25 m/min, feed of 0.25 mm/rev. Calculate: (1) the time of cutting to complete the drilling operation, and (2) metal removal rate during the operation.

Q1\ a) The operation of drilling is to be done with a 25.4 mm ( diameter) twist drill in a brass workpiece. The hole is a blind-hole with the point angle = 118°, and a depth of 50 mm. The speed of 25 m/min, feed of 0.25 mm/rev. Calculate: (1) the time of cutting to complete the drilling operation, and (2) metal removal rate during the operation.

Precision Machining Technology (MindTap Course List)

2nd Edition

ISBN:9781285444543

Author:Peter J. Hoffman, Eric S. Hopewell, Brian Janes

Publisher:Peter J. Hoffman, Eric S. Hopewell, Brian Janes

Chapter4: Drill Press

Section4.1: Introduction To The Drill Press

Problem 3RQ: Explain how the size of an upright drill press is determined.

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