A three-axis CNC machining center is tended by a worker who loads and unloads parts between machining cycles. The machining cycle takes 5.75 min, and
A three-axis CNC machining center is tended by a worker who loads and unloads parts between machining cycles. The machining cycle takes 5.75 min, and the worker takes 2.80 min using a hoist to unload the part just completed and load and fixture the next part onto the machine worktable. A proposal has been made to install a two-position pallet shuttle at the machine so that the worker and the machine tool can perform their respective tasks simultaneously rather than sequentially. The pallet shuttle would transfer the parts between the machine worktable and the load/unload station in 15 sec. Determine (a) the current cycle time for the operation and (b) the cycle time if the proposal is implemented. What is the percentage increase in hourly production rate that would result from using the pallet shuttle?