110 likes | 268 Views
UEET 606 Modern Manufacturing and Quality Control. Manufacturing Models. Production performance. Production rate: Usually expressed as an hourly rate for an individual processing or assembly operation Work units completed per hour Cycle time = time one work unit spends being processed (T c )
E N D
UEET 606 Modern Manufacturing and Quality Control Manufacturing Models
Production performance • Production rate: • Usually expressed as an hourly rate for an individual processing or assembly operation • Work units completed per hour • Cycle time = time one work unit spends being processed (Tc) • Not all of it is productive Introduction to Manufacturing Systems
Batch and job shop production • Batch processing : • Assume the batch consists of Q number of parts • Total time = set up time + Q*Tc • The average production time per unit is the total time divided by the number of units in the batch Introduction to Manufacturing Systems
Mass Production • In mass production the effects of setup time are insignificant • The production rate is the reciprocal of the cycle time Introduction to Manufacturing Systems
Production Capacity • Maximum rate of output that a production facility is able to produce under a given set of operating conditions • Also referred to as PLANT CAPACITY Introduction to Manufacturing Systems
Utilization and availability • Amount of output of a production facility relative to its capacity • Actual quantity produced divided by the production capacity • Examples 1 and 2 Introduction to Manufacturing Systems
Utilization and availability • Availability is a measure of how reliable an equipment is. • It is defined by two terms: • Mean time between failures (MTBF) • Mean time to repair (MTTR) • Availability = (MTBF – MTTR)/MTBF Introduction to Manufacturing Systems
Manufacturing Lead time • Total time required to process a given part or product through plant. • It includes: • Productive time • Non – productive time (e.g. delays, inspection, storage, materials handling, etc) Introduction to Manufacturing Systems
Manufacturing Capability • Technical and physical limitations of a plant • Technical - available set of manufacturing processes • Physical - limitations such size, weight • Production capacity - quantity that can be produced within a given time period (plant capacity) Introduction to Manufacturing Systems
Cost of Manufacturing • Typically, total cost of making a product is 40% of its selling price • Two major classifications: • A) Fixed + Variable costs ( = Total cost) • Fixed cost – constant no matter level of manufacturing • Examples – taxes, overheads, • Variable costs – change with level of manufacturing • Examples – material costs Introduction to Manufacturing Systems
Cost of Manufacturing • B) Direct Labor, Materials and Overheads • Direct labor = operator wages • Materials – raw materials • Overheads – factory, corporate Introduction to Manufacturing Systems