Facility Layout Dr. Everette S. Gardner, Jr.

Facility Layout2 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

Facility Layout3 Product layout Raw matl. Fabrication Rec- storage line-part B eiving Fabrication Planer line-part A Finished Lathe goods Drill storage Mill Mill Drill Grinder Mill Assembly line Automatic Small number of high volume products

Facility Layout4 Possible solutions to the process layout problem 6 Department problem has 6! or 720 possible solutions: A B C D E F I.E., there are 720 different arrangements of the 6 departments on the 6 locations on the grid.

Facility Layout5 Possible solutions to the process layout problem (cont.) Problem complexity grows exponentially: Nbr. depts. Solutions 10 3,628, x 10^ x 10^ x 10^64

Facility Layout6 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 Layout7 Craft initial layout of furniture plant A B C D E F G I H J TOTAL COST = $

Facility Layout8 Craft final layout A E C I G F B H J D TOTAL COST = $766.68

Facility Layout9 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 Layout10 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 Layout11 Line balancing quiz 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. A B C D E F G H IJ

Facility Layout12 Multiple solutions in line balancing A B C D E F G H

Facility Layout13 Multiple solutions in line balancing (cont.) Stations Number of solutions

Facility Layout14 Volvo layouts Rotating round table with definite cycle time -- facilitates teamwork

Facility Layout15 Volvo layouts (cont.) Horseshoe conveyor sections to enable worker communications

Facility Layout16 Volvo layouts (cont.) Interim storage Storage areas to separate line into definite supervisory groups Supervisor Supervisor B A

Facility Layout17 Volvo layouts (cont.) Machines grouped in banks of 3 so workers can exchange jobs and assist each other in set-up

Facility Layout18 Volvo continued Connections of subassembly islands feed parts/components to end-assembly islands—each island functions as a separate team E S S S E E S S S