EQUALIZING PROCESS CYCLE TIME AND PROCESS THROUGHPUT, THE KEY TO “WORLD CLASS MANUFACTURING”

摘要

Two commonly used metrics to determine the performance of an assembly line are “Cycle Time” and “Throughput”. These two metrics are often used interchangeably. However they have two very distinct definitions. “Cycle Time” is the absolute speed at which any particular product can be produced on that particular assembly line. “Throughput” is how many “good” products can be produced on that particular assembly line in a given time period. “Good Products” are defined as products that pass all tests (in circuit, functional, etc.) the first time the products are tested with NO in process touch up or repair. An assembly line will maximize its profitability if it can equalize “cycle time” and “throughput”. The benefits and competitive advantage of every product that is built being “shippable” with no rework or repair are numerous and obvious. However no electronic manufacturing process has ever been able to equalize cycle time and throughput and it is unrealistic to imagine any process ever being able to do so. However every electronic manufacturing operation should have a goal supported by a detailed plan and schedule to equalize process cycle time and throughput. To develop an improvement plan we must first understand ALL the factors that influence how well any particular operation can insure that all the products they build will pass all tests the first time with no rework or repair. The intent of this paper is to discuss the specifics of cycle time and throughput, understand how these metrics are calculated, discuss process equipments role in equalizing process cycle time and process throughput and understand the approach required to optimize the throughput of a process.