Reduction of manufacturing lead-time through selection of machining rate and unit handling size

When parts are on the shop floor and in manufacture, they are either waiting for or are being attended by a machine or a material handling equipment. When several workstations are required to process a job, the machining and moving of the parts between the workstations can be very time consuming unless it is properly planned. When poorly planned, the processing and handling decision can significantly affect the length of time the job spends in the shop. In this paper, a methodology for planning the machining and the material handling activities for the manufacture of small to medium size batches in a job shop is presented. The model determines the machining rater at each workstation and the unit-load size to use in handling the batch through the production system in order to minimize the total production time. The procedure is easy to implement on a microcomputer for use in planning shop production activities.