(35 points) Consider an experiment to improve a heat treatment process on truckleaf springs reported in Pignatiello and Ramberg (1985). The heat treatment whichforms the camber (or curvature) in leaf springs consists of heating in a high tem-perature furnace, processing by a forming machine, and quenching in an oil bath. The height of an unloaded spring, known as free height, is an important qualitycharacteristic whose target value is 8 inches. An experimental goal is to make thevariation about the target 8.0 as small as possible.

The five factors listed in Ta-ble 1 were chosen across the various stages of the process:

(A)furnace temperature

(B)and heating time

(C) are from the heating stage, transfer time

(D) is the time ittakes the conveyer to transport the springs from the furnace to the forming ma-chine, hold-down time

(E) is the time that the springs are held in a high pressure

Ashielded metal arc-welding operation is accomplished in a work cell by a fitter and a welder. the fitter takes 5.5 min to load components into the welding fixture at the beginning of the work cycle, and 1.5 min to unload the completed weldment at the end of the cycle. the total ength of the weld seams 1200 mm, and the travel speed used by the welder averages 300 mm/min. every 600 mm of seam length, the welding stick must be changed, which takes 0.8 min. while the fitter is working, the welder is idle (resting): and while the welder is working the fitter is idle. (a) determine the average arc-on time as a fraction of the work cycle time. (b) how much improvement in arc-on time would result if the welder used flux-cored arc welding (manually operated), given that the spool of weld wire must be changed every 10 weldments, and it takes the welder 5.0 min to accomplish the change? (c) what are the production rates for these two cases (weldments completed per hour)? attach your work and solutions.