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Facility Layout. Dr. Everette S. Gardner, Jr. Machine shop process layout. Receiving Grin- Mills ders Raw matl. Large number of storage Assem- low volume bly products Drills Planers Finished Inspec- goods Lathes Automatics tion storage Part A Part B . Product layout.
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Facility Layout Dr. Everette S. Gardner, Jr.
Machine shop process layout Receiving Grin- Millsders Raw matl.Large number of storage Assem-low volume blyproducts Drills Planers Finished Inspec-goods LathesAutomatics tionstorage Part A Part B Facility Layout
Product layout Raw matl.Fabrication Rec- storageline-part B eivingFabrication Planer line-part A FinishedLathe goodsDrill storage Mill Mill Drill Grinder Mill Assembly line Automatic Small number of high volume products Facility Layout
Possible solutions to the process layout problem 6 Department problem has 6! or 720 possible solutions: ABC DEF I.E., there are 720 different arrangements of the 6 departments on the 6 locations on the grid. Facility Layout
Possible solutions to the process layout problem (cont.) Problem complexity grows exponentially: Nbr. depts.Solutions 103,628,800 151.31 x 10^12 202.43 x 10^18 503.04 x 10^64 Facility Layout
Solutions considered by Craft • N! solutions to problem with N depts. • Craft considers only N(N-1) pairs of exchanges, 2 starting with each dept. Facility Layout
Craft initial layout of furniture plant A B C D E F G IH J TOTAL COST= $2524.68 Facility Layout
Craft final layout A E C IG F B H J D TOTAL COST = $766.68 Facility Layout
Synopsis of assembly line balancing 1. Set up a precedence table. 2. Compute required cycle time: C = (production time) / (required output in units) 3. Compute minimum cycle time: CMIN = time for longest task 4. Compute minimum number of stations: SMIN = (sum of all times) / C Facility Layout
Synopsis of assembly line balancing (cont.) 5. Select rule by which tasks are assigned to work stations. Examples: (1) select tasks with longest operation times first or (2) select tasks with largest number of following tasks first 6. Assign tasks to the first work station until the sum of the task times are equal to the cycle time, or no other tasks are feasible. Repeat for stations 2, 3, … until tasks are assigned. 7. Evaluate the efficiency of the balance: E = (sum of all times) / (actual nbr. of stations x C) Facility Layout
Line balancing quiz 0.4 0.3 1.1 1.1 0.5 0.7 0.3 1.2 0.4 0.8 Balance this production line to achieve an output of 367 units per day. Available production time is 8 hrs. less a 40 min. lunch break. Use the largest number of following tasks rule to select tasks for work stations. Break ties with the longest operation time. B E G C A I J D F H Facility Layout
Multiple solutions in line balancing 6 4 7 3 5 5 5 2 B F C H A D G E Facility Layout
Multiple solutions in line balancing (cont.) 84 25 3 1 2 3 4 5 6 7 Stations Number of solutions Facility Layout
Volvo layouts Rotating round table with definite cycle time -- facilitates teamwork Facility Layout
Volvo layouts (cont.) Horseshoe conveyor sections to enable worker communications Facility Layout
Volvo layouts (cont.) Interim storage Storage areas to separate line into definite supervisory groups SupervisorSupervisor BA Facility Layout
Volvo layouts (cont.) Machines grouped in banks of 3 so workers can exchange jobs and assist each other in set-up Facility Layout
Volvo continued Connections of subassembly islands feed parts/components to end-assembly islands—each island functions as a separate team E S S E S S E S S Facility Layout