6. Suppose a lean engineer creates an "interim" machining cell, run by one operator initially, and single-cycle-automatic type (SCA). The cell layout and its operating times the machines are all are shown below. VM Drill Press Drill Press Grinding Finished part cart D Lathe Raw Auto Cutoff mat Saw Machine Tool Operation or Process Machining Times (MT) (min) Operator Manual Time (min) Operator Walk Time (min) Auto Cutoff Saw Cut tube to length 0.25 0.40 0.10 Turn OD on Lathe 134 0.5 0.25 0.10 inset Lathe 264 Turn barrel ID 1.0 0.25 0.05 Drill press 325 Drill holes for bolt circle 1.3 0.30 0.05 Drill press 326 Tap holes in ring 1.6 0.25 0.10 Vertical milling Mill primary 0.8 0.30 0.10 machine (VMC) groove Grind 0.002 in. Large Grinding Machine 0.40 0.05 from surface 0.8 'A' 'Unloading the machined part, visually inspecting the part, deburring, loading next part, etc. Time to walk from machine to machine. S S S a) Assuming this cell is run by one operator, what is the NCT of the cell, in minutes/part? a. 8.95 mins per part b) What is the production rate, using your NCT from question a, in parts/hour? a. 2.07 parts per hour c) Assume the stock-on-hand (SOH) in this cell consists of one unit at each machine. For now, ignore any WIP in the decouplers. For one part moving through the cell with one operator, what is the throughput (in minutes)? Throughput is often referred to as Lead Time. d) If we activate the four decouplers shown in the layout, and on average there is 0.9 units of WIP at each decoupler, what is the throughput? Assume there is still one operator, working in MO-CO-MOO fashion. e) Assume the takt time decreases so that the NCT must be reduce accordingly. If you add a second operator, what is the approximate NCT? f) From your results in question e, is the design rule for the cell still being met? What are the implications for the workers and machines