Optimal Facility Layout Design for Continuous Process Industry

Introduction to Facility Layout Concepts

To understand what an optimal facility layout is, it is helpful to first understand the general concept of facility layout. For a large manufacturing facility producing a product, the general facility layout refers to the interrelated physical arrangements—existing or proposed—of workstations, departments, common areas, and storage areas. These arrangements are designed to permit the synchronous movement of materials, workforce, and transportation of raw materials, semi-finished goods, and finished goods, as well as tools and consumables within the facility, in a smooth and efficient manner. Most layout decisions are highly labor- and logistics-centric, endeavoring to enhance worker efficiency, improve production methods, and introduce automation. An important requirement is the measurement of the response system and adjusting one's design, production volume, and product mix to obtain the best results. In addition, layout planning addresses idle time, bottlenecks, material handling issues, equipment utilization, and the general increase in production (Maniya & Bhatt, 2011; Sule, 1994).

To understand how an optimal facility layout is conceived for a continuous process industry, a combination of semi-heuristic techniques and step-by-step algorithmic methods is deployed. An intelligent blend of the CRAFT algorithm with a Hungarian assignment algorithm provides efficient results in terms of computer CPU usage time and appears to yield a faster outcome than the purely heuristic CRAFT algorithm alone (Khoshnevisan et al., 2003).

Technically speaking, CRAFT is a computerized algorithm based on heuristic principles. It accumulates the entire load from inter-departmental transaction costs of company operations and stores it as a block layout, which may be either an existing or an arbitrary one. The updated data and load matrix are stored in RAM after the algorithm has exhausted every possible combination its software can accommodate. All CRAFT developments adhere to heuristic patterns and are consequently CPU-intensive (Khoshnevisan et al., 2003).

The optimal facility layout is a fundamental optimization problem faced by diverse manufacturing and service organizations. The problem concerns the relocation of areas and facilities to achieve cost-effectiveness by minimizing the expenses involved in rationalizing the movement of products or services within the available facility space. In other words, space and work-stage areas are planned so as to reduce logistics costs to a minimum (Mallette & Francis, 1972).

Strategic Importance of Optimal Facility Layout

An optimal facility layout may involve one or several features, including employee safety and morale, uninterrupted flow of material and data, optimal utilization of space, machinery, and personnel, customer satisfaction, and total flexibility in approach.

Optimal facility layouts are categorized into the following types: fixed-position layout, office layout, retail layout, process-oriented layout, warehouse layout, and product-oriented layout (Heizer & Render, 2001).

Facility Layout and Location Planning

Facility Layout

This area of operations management encompasses process selection and facility layout. While process selection addresses the organization of goods and services production—including capacity planning, facility layout, and equipment and work system design—process strategy concerns equipment and labor allocation, flexibility, and adaptation to change. Process types are divided into job, batch, repetitive, and continuous categories, ordered by volume of production. Automation is conceived in terms of fixed and programmable configurations, supported by robots and computer-integrated manufacturing facilities (Stevenson, 2012).

Facilities layout refers to the placement and configuration of the various entities of a plant, including equipment, work centers, and the flow of materials and personnel. Conceiving a layout is important from the perspective of investment requirements, long-term commitments, and its considerable bearing on the efficiency-to-cost ratio in short-term application. Layout changes are typically necessitated by costly bottlenecks, environmental issues, changes in production volume or product mix, morale problems, or anticipated changes in manufacturing methods and equipment. Layout plans normally follow product process, fixed-position, or combination layout types. Among these, product layout is prominent due to its diverse advantages, including speed, low cost, and high utilization of both personnel and machine hours. However, this system tends to lack flexibility in response to change. A process of line balancing is also introduced to distribute workload equally across workstations. Process layouts can handle diverse processing demands without significant vulnerability to failures and can operate with less expensive equipment and individual incentive plans. Fixed-position layout involves moving materials and personnel while the product and workstation remain stationary. Cellular layouts involve the formation of a machine cell where components with similar processing requirements can be handled efficiently.

Linear programming refers to a progression of operations that culminates in an optimal solution, if one exists. The steps in linear programming include: (a) formulating a mathematical objective function and its constraints, (b) plotting the constraints, (c) identifying feasible solutions, (d) plotting the objective function, and (e) identifying the optimal solution.

Location Planning

Location planning is an important strategic element for any company seeking growth and competitive advantage. Location planning techniques deal with expanding current facilities at the same site, relocating to a new site, creating additional locations, or maintaining the status quo. Several factors—such as identification of the optimal nation, region, community, and site—prove critical in decision-making.

Factors affecting location selection, such as proximity to raw materials, accessibility to target markets, and regional climate and culture, are evaluated using the center of gravity model, factor rating, and the transportation model to assess suitability for the purpose at hand (Stevenson, 2012).

Conclusion

Optimal facility layout represents the culmination of data processing, production planning, and operations management in a manufacturing or service setting. A well-conceived layout can achieve significant benefits through single-line flow of materials and work-in-progress items, leading to substantial cost reductions. When these savings are passed on to the consumer, they contribute to a healthy balance sheet. In addition, optimal layout contributes to employee efficiency and wellbeing, and the underlying principles can be applied to the service sector as well as to industries beyond traditional manufacturing.

References

Chakraborty, S., & Banik, B. (2007). An analytic hierarchy process (AHP) based approach for optimal facility layout design. Journal of the Institution of Engineers, Part PR: Production Engineering Division, 88, 12–18.

Heizer, J., & Render, B. (2001). Operations management (PowerPoint ed.). Prentice Hall.

Jannat, S., Khaled, A. A., & Paul, S. K. (2010). Optimal solution for multi-objective facility layout problem using genetic algorithm. International Conference on Industrial Engineering and Operations Management, Dhaka, Bangladesh.

Khoshnevisan, M., Sukanto, B., & Smarandache, F. (2003). Optimal plant layout design for process-focused systems.

Mallette, A. J., & Francis, R. L. (1972). A generalized assignment approach to optimal facility layout. AIIE Transactions, 4(2), 144–147.

Maniya, K. D., & Bhatt, M. G. (2011). An alternative multiple attribute decision making methodology for solving optimal facility layout design selection problems. Computers & Industrial Engineering, 61(3), 542–549.

Ronald, J. O., Davina, L., Ron, Z. G., Jennifer, A. B., Kathleen, R. R., Fikry, I., & Sara, W. (2002). Long-term impact of Johnson & Johnson's Health & Wellness Program on health care utilization and expenditures. Journal of Occupational and Environmental Medicine, 44(1), 21–29.

Sule, D. R. (1994). Manufacturing facilities: Location, planning and design (2nd ed.). PWS Publishing.

Stevenson, W. J. (2012). Operations management (11th ed.). McGraw-Hill Irwin.