The base part of a piston assembly is shown below. The part outer dimensions are: length 76 mm width 64 mm, height 30 mm. The part volume is 29 cm and it is to be molded from ABS. The maximum wall thickness is 3.0 m FIGURE 8.19 Pneumatic piston assembly base part You have obtained a quote of 8,000 for a single-cavity mold for the part. However, large quantities of the part are required justifying the use ofa 4-cavity mold, which means for each injection cycle, parts will be produced. For the proposed 4-cavity mold production, estimate the following: a. The appropriate machine size from the selection in Table 8.4 (table for Injection Molding Machine), making an approximate allowance for the projected area of the runner system as well as the four cavities
b. The likely molding machine cycle time.

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.