Question

answer a) is 1.35 and b) 7.16 i want the answer for c Problem #4 A slab milling operation is performed on the top surface of a steel rectangular workpiece 12.0 in fong by 2.5 in wide. The helical milling cutter, which has a 3.0 in diameter and ten teeth, is set up to overhang the width of the part on both sides. Cutting speed is 125 ft/min, feed is 0.006 in/tooth, and depth of cut - 0.300 in.? Determine (a) the actual machining time to make one pass across the surface and (b) the maximum metal removal rate during the cut. (c) If an additional approach distance of 0.5 in is provided at the beginning of the pass (before cutting begins), and an overtravel distance is provided at the end of the pass equal to the cutter radius plus 0.5 in, what is the duration of the feed motion.

Answer 1

solution, . La Given da @ Machining time Ne VIIDE 125 (2)/3x1 = 159.15 dev/min fr = Nrif = 15945 x 10 x. (0.006) = 9.549 in /min A = (d CD-d))"? (0.30 (3.0 -0:30).5 0.90 in Tm = (k+A) /fr = (12 +0.9)/9.549 +1-350. min. @ maximum metal Gemoval Sate during the wet, : RMR = wd fr = 2.5x 0.30 x 9.549 = 7.16 ins/min @ The cuttur travels 0.5 in before making contact with the work. It moves 0.90 in before reaching full depth of cut. It then feeds the length of work (12.0 in) the ones travel consists of cuttur sadius (1.5 in) plus an additional 0.5 in thus, T7 - (0.5+0.9 + 12.0+105+0.5)/9.549 = 1.613 min.' I