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PART B: TECHNOLOGY DESIGN PROBLEM

I. ) Consider the following component to be machined in a slab milling machine. Themachining has to be done only on the three surfaces marked. Other surfaces are left as cast.Assume that an allowance of Imm on the machined surfaces to be removed in single passon each side. The slab milling cutter of 70mm diameter and 160mm long with 8 teeth isused. The maximum allowed cutting speed is 20m/min. The maximum feed per tooth isO.lmm. The specific power, mechanical efficiency and correction factor can be assumed as1.3 Ws/mm" 75 % and 1.15. Neglect the cutting allowance. You can neglect themachining stock for calculation. (20 Marks)

Find out the following:a) The maximum rpm ofthe cutterb) The maximum possible width ofthe cut at any time, in mmc) The maximum feed per minute in mmlmind) The total cutting time to machine the three faces in mine) The maximum possible MRR in mm3/mint) The actual MRR with no allowance in mm 3/ming) The maximum motor power required in Wattsh) The total machining cost( Assume $2751hr) in $

P specijicpower *MRR *CFower = = - ~ ' - - - ' ' - - - - - - - - -77

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2 marks2 marks2 marks3 marks3 marks3 marks3 marks2 marks

100mm

1 0 0 ~ : : L : L-__________ ' - - ] 5 150mmI. 200mm I

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7/27/2019 Midterm Last Question Solved

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7/27/2019 Midterm Last Question Solved

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