Question

Calculate the machining time for drilling 4 holes of 16mm dia latch on a flange from the following dat(a) Flange thickness = 30 mm, cutting speed  = 22mpm feed =0.2mm/rev                                  

(a) 1.9 min                      (b) 1.6 min

(c) 2 min                         (d) 2.3 min