Management Engineering - Operations Management

Full exam

Exercise 2 ( 12 points) The Christmas Everyday Company p roduces high quality professional ski s for winter sport teams . The range of this product family is composed by a combination of 5 different sizes and 12 different surface painting. The customer demand is based on a combination of five different sizes and 12 surface paintings leading to 60 variants. The average demand is equal to 400 units per day, the daily demand is not so stable (+/- 25%) and everyda y all the variants are requested by the customers, who are not willing to wait for the products . Production process: The production system is composed by the following stages: Machining: this stage is 50% of the time dedicated to this family product. There are two operators that use a manual machine and work in parallel on different pieces. Cutting: there are 2 operators that work in parallel in two different table s. Each operator works with manual tools and he does a ll the activities necessary to cut the item : the cutting process is composed by 6 different serial steps that take more or less the same time. A setup is necessary when product size changes; Finishing: there is one operator that uses a manual machine; a setup is necessary when product size changes; Chemical painter : there is one operator that uses a n automatic machine. A setup is necessary when the variant changes. Packaging : there is an operator that use s an automatic machine. A setup is necessary when the variant changes. Each shift lasts 8 hours and there are two 15 -minutes breaks per shift. All stages (except of machining stage) are completely dedicated to this product family. Upstream the production system, there is a stock of raw material of 3500 pieces . There is no scrap in any process . Stations Cycle Time (sec.) (single operator) Changeover (min .) Availability (%) Shift per day Inventory (downstream) Machining 100 0 90 3 30 00 Cutting 110 50 (size) 95 2 4500 Finishing 100 30 (size) 100 2 2500 Chemical painter 15 0 50 ( variant ) 95 3 50 00 Packaging 14 0 10 (variant ) 85 3 40 00 The company receives everyday customer orders through emails . Every day the production control function plans manually several deliveries. The production control function issues a weekly production plan manually for each production stage. Tw ice per week , the first s tage (Machining) informs production control function about the raw material inventory level. The production control function places a raw materials order to the supplier every two we eks. Once per month it makes a forecast about the consumption of raw -materials and sends it to the supplie r. Every two weeks the company ord ers raw materials to the supplier and the supplier deliver s the day after the order. Q1) (1,5 points) Compute the EPE for the cutting stage . Q2) (2,5 points) Draw the current -state map of the operations system ( timeline included ) Q3) (8 points) Create a future -state map of the system (answer ing the first six questions of the future state): Define the minimum changes in order NOT to exceed 42 00 units (sum of Raw -Materials, WIP /FIFO ) and NOT to exceed 2000 units in the finished good warehouse (assuming that it is not possible to modify Supplier inter -arrival time, Availability, CT and shifts in future state improvement targets) . For exam resolution , assume a security coefficient of 1,5 for WIP /FIFO and of 2 for finished product in the sizing of the supermarkets . To size the FIFO consider as 133 units the demand in one shift, ( 400 pieces/3 shifts).