Mechoff case Job Shop basic exercise

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1 JOB SHOB – BASIC EXERCISE A small manufacturing company is currently designing a new production system, organized in job shops. It is installing 3 different departments (M1, M2, M3), which will serve to produce at least 3 types of product (A, B, C). We have the following information: Product Production process (Department, Cycle Time [min / pcs]) Average annual demand (pieces) A (M1, 15) – (M2, 10) 15000 B (M1, 9) – (M3, 8) 25000 C (M2, 17) – (M3, 7) 35000 Those are the starting data we need, without them we can’t work The production system will work 3 shifts of 7 hours per day, 240 days/year. Departments have different coefficient. M1 considers a human coefficient (HC) of 0.96 and an Availability (A) of 0.96. M2 considers a human coefficient (HC) of 0.95 and an Availability (A) of 0.93. M3 considers a human coefficient (HC) of 0.91 and an Availability (A) of 0.93. The scheduling efficiency (SE) must be set equal to 0.82. M1 scrap rates (SR) is equal to 0.07, M2 scrap rates is equal to 0.05, while M3 scrap rates is equal to 0.09. In M1 department, setup lasts 2.8 hours for each change of production; in M2 setup lasts 2.3 hours for each change of production; in M3 setup lasts 1.9 hours for each change of production. It is expected to produce average batches of about 1000 pieces (regardless of the type of product). The objective is to determine the number of machines and the rate of saturation for each department (NB: not for the product). NOTES In this exercise the processing cycle is given We have to multiply the STT for 60, in order to have the result in min The scrap rate here is given on the base of the machine, but it can happen that it’s different for each product. We should use the safety coefficient, here relevant for Department 1. Here there is no trial rate,…