Department of Mechanical Engineering|
Semester Test 2 - 2011|
Manufacturing Systems MVS 311|
Date - 15 April 2011|
Duration – 90 minutes This is an open book examinationInternal examiner: Mr E.T. BrettExternal examiner: Mr. J.J. Pienaar| * Answer ALL THE questions. * State and motivate all assumptions clearly. * Please Note: All questions do not carry the same marks. * This paper consists of 2 pages| |
a Establish the initial total length of a 12 mm round material slug required to manufacture a bolt by upset forging the bolt head and by impact extruding the shank portion where the thread is required. The bolt has the following dimensions (12 mm shank diameter, 20 mm unthreaded portion of shank, 30 mm length of threaded portion on the shank, m12 x 1.75 thread with a bolt shank pitch diameter of 10.75 mm, 19 mm bolt head width across flats, 8 mm bolt head thickness). b The first station of a wire drawing process is utilised to reduce the area of a 8 mm rod by 25%. at each station i. Calculate the new diameter of the rod after the first station. ii. Calculate the diameter of the “wire” after it has passed through four stations. iii. Establish the percentage increase in length of the wire after the wire has passed through the four stations.
a Describe how the electroplating process applicable to “plastics” functions. b Under what circumstances would the following finishing processes be used: i. Cladding,
Describe what the following mean to you (provide sketches to clarify your answer) a Metal removal rate (state as well the appropriate ISO units that will be used to measure the metal removal) b It is more economical to take a cut with a small feed than a small cut with a large feed. c A surface planer as well as a shaper consume excess energy due to the...