Layout decisions entail determining the placement of departments, work groups within the departments, workstations, machines, and stock-holding points within a production facility.
This chapter examines how layouts are developed under various formats or work-flow structures. The emphasis is on quantitative techniques but examples of qualitative factors are also included in layout design. Both manufacturing and service facilities are included. When designing the layout of a facility, decisions have long-term consequences in both cost and the firm's ability to serve its market(s). Management must take the time to identify and evaluate layout alternatives. The objective for a layout is to provide a smooth work flow of material through a manufacturing facility or an uncomplicated traffic pattern for customers and employees in a service system.
A process or flow shop layout groups similar equipment or functions together. A product layout groups equipment or work processes according to the steps by which the product is made. Group technology layout groups dissimilar machines into work centers, or cells, to work on products that have similar shapes and processing requirements. The final layout, a fixed-position layout, produces the product at one location.
Process layout focuses on minimizing material handling cost or customer and worker travel times. Computerized layout programs are useful in devising good processing layouts. The original program is CRAFT, or the Computerized Relative Allocation of Facilities Technique.
Product layouts focus on making the product flow easier. As product demand increases, it becomes cost effective to use an assembly line layout for processing. The assembly line consists of a series of workstations with a uniform processing time interval between each workstation.
Line balancing means that tasks are assigned to a series of stations so that the time required at each station is less than or equal to the cycle time and processing time is minimized. Tasks can be balanced, or minimized, by splitting the tasks, by duplicating by number of stations dedicated to a task, sharing the tasks by a neighboring station, using more skilled workers, working overtime, or redesigning the tasks.
Mixed Model Line Balancing
While the earlier assembly lines were designed for assembling one one product at a time in a continuous fashion, Toyota Motors has come out with mixed model assembly lines wherein number of different products are assembled in the same day actually within the same hour. Now operations managers have to learn this technique to become world class operations managers.
The note by Chase et al. discusses the issues of flexible and U-shaped line layouts as well as the use of computerized line balancing and mixed-model line balancing. Current views on assembly lines try to incorporate greater flexibility in products produced on the line, more variability in workstations, improved reliability, and high-quality output. A reading on Dell Computer is included to illustrate current thoughts on assembly lines.
Layouts of facilities are important in service and retail service businesses as well as in assembly and manufacturing. In retail services, layout specialists and planners must consider servicescapes, ambient conditions, spatial layout and functionality, and even signs, symbols, and artifacts.
Industrial engineers evaluate layout from the efficiency perspective and keep doing improvements to reduce material handling and movement of operators etc. Even the U layout promoted by Toyota Motors came out as a result of improving efficiency by encouraging operators with high natural speed of working to help operators experiencing delays. Thus group work is brought into picture in production cells so that line output is maintained within standards.
Basic Production Layout Formats
Process Layout Defined
Product Layout Defined
Group Technology (Cellular) Layout Defined
Fixed-Positing Layout Defined
Computerized Layout Techniques - CRAFT
Systematic Layout Planning
Systematic Layout Planning (SLP) Defined
Workstation Cycle Time Defined
Assembly-Line Balancing Defined
Precedence Relationship Defined
Flexible and U-Shaped Line Layouts
Mixed-Model Line Balancing
Current Thoughts on Assembly Lines
Group Technology (Cellular) Layout
Developing a GT Layout
Virtual GT Layout
Retail Service Layout
Spatial Layout and Functionality
Signs, Symbols, and Artifacts
Case: Soteriou's Souvlaki
Case: State Automobile License Renewals
Full Material from the Book of Chase on Facility Layout
Full Material from the Book of Chase on Facility Location
Updated 7.12.2014, 3.2.20102
Summaries of all Chapters of Operation Management
MBA Core Management Knowledge - One Year Revision Schedule