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  1. KIOT Plant Layout and Facility Design Course code: Greg 4181 Target group: 4th year GED Chapter three Plant Layout By: Endashaw Yohannes Kombolcha/Ethiopia Dec, 2019 12/26/2019 1
  2. 1. Meaning of plant layout 2. Objective of plant layout 3. Symptoms of bad layout 4. Advantages of good plant layout 5. Principles of plant layout 6. Types of layout 7. General flow patterns of plant layout Outline of chapter three
  3. “Plant layout is a plan of an optimum arrangement of facilities including Personnel, Operating equipment, Storage space, Material handling equipment and All other supporting services along with the design of best structure to contain all these facilities”. 1. Meaning of Plant Layout
  4. 2. Objectives of Plant Layout o The primary goal of the plant layout is to maximize the profit by arrangement of all the plant facilities to the best advantage of total manufacturing of the product and at the same time satisfactory and safe for the personnel doing the work.
  5. 2. Objectives of Plant Layout cont... o Helps for the personnel doing the work. In the Sense of Unity o The feeling of being a unit pursuing the same objective. Minimum Movement of people, material and resources. Safety o In the movement of materials and personnel work flow. Flexibility o In designing the plant layout taking into account the changes over short and medium terms in the production process and manufacturing volumes.
  6. 2. Objectives of Plant Layout cont... • These main objectives are reached through the attainment of the following facts: Congestion reduction. Elimination of unnecessary occupied areas. Reduction of administrative and indirect work. Improvement on control and supervision. Better adjustment to changing conditions. Better utilization of the workforce, equipment and services.
  7. 2. Objectives of Plant Layout cont... Reduction of material handling activities and stock in process. Reduction on parts and quality risks. Reduction on health risks and increase on workers safety. Moral and workers satisfaction increase. Reduction on delays and manufacturing time, as well as increase in production capacity.  All these factors will not be reached simultaneously, so the best solution will be a balance among them.
  8. Introduction • To make a decision about layout planning, 4 different questions must have an answer: 1. Which centers do we have to consider? 2. How much space and capacity is required for each center? • If there is not enough space, productivity may be reduced. • Too much space is expensive and may also reduce productivity. 3. How must the space be related with each center? • Space quantity, shape and the elements of the work center are related to each other. 4. Where should each center be located at within the facility? • The allocation of the different centers may affect productivity.
  9. Design problem Green field/current state Location of one new machine • Reasons to design production layout: New products Changes in demand Changes in product design New machines Bottlenecks Too large space between work station Too long transfer times Production Layout
  10. Layout Design Layout Product Logistics Process
  11. o Re design of production layout • The reasons for a re-layout are based on 3 types of changes: Changes in production volumes. Changes in processes and technology. Changes in the product. • The frequency of the re-layout will depend on the requirements of the process.
  12. 4. Symptoms of bad layout Symptoms that allow us to detect the need for a re-layout: Some machines heavily loaded and some idle Excessive handling by skilled workers Long production cycles & delays on delivery Crowded condition & Poor utilization of available space Bottleneck in production & obstacles in material flow Excessive fatigue on workers & frequent accidents Excessive temporary storage & Backtracking Difficult in supervision and control Idle machines and manpower
  13. Figure: improper production layout
  14. 3. Advantages of good plant layout Reduce internal transport to a minimum Minimizes accidents operations Makes supervision & production control easier Makes maintenance and repair easier Reduces labor turnover Reduces production delay Maintain floor area neat and clean Reduces waste effort, wastages and spoiled work Reduces back tracking and bottlenecks Better utilization of manpower and machinery Possible to improve production methods
  15. •Any layout should satisfy the objective or principles of plant layout for proper functioning. •There are Nine basic principles of best plant layout 1. Principle of overall integration 2. Principle of minimum distance moved 3. Principle of flow 4. Principle of cubic space 5. Principle of satisfaction and safety 6. Principle of flexibility 7. Principle of expansion 8. Principle of versatility 9. Principle of orderliness 5. Principles of plant layout
  16. Basic principles of plant layout 1. Principle of overall integration o The layout is best which integrates Men, Material, Machinery, and Supporting activities in a way that results best compromise. o It must be convenient for people servicing or supporting the operation as well.
  17. 2) Principle of minimum distance moved Other things being equal the layout is best which permits the material to move the minimum distance between operations. By placing subsequent operations adjacent to each other reducing the we can reduce distance of movement .
  18. 3) Principles of flow Other things being equal, the layout is best which arranges the work area for each operation or process in the same order or sequence that forms , treats, or assembles the materials. It means that material will move progressing from one operation to the next towards its completion. Congestion with other parts or other pieces of the same part is at minimum.
  19. 4) Principle of cubic space • Other things being equal, the best layout utilizes effectively all available space both vertical and horizontal. • Movement of material, men and machinery may be in any of the three direction. • It means taking vacant overhead space or work surface under the floor.
  20. 5) Principle of satisfaction and safety Being other things equal, the layout is best which makes work satisfying and safe for workers. Safety is the major factor in most layouts. A layout can not be good if it subjects employees to hazardous or accidents.
  21. 6) Principle of flexibility Other things being equal, the layout is best which can be adjusted and rearranged at minimum cost and inconvenience. This objective become more important ,as new developments are taking place in scientific research for frequent changes in product design, equipment and production methods. Economy can be obtained if a new layout can be made quickly and inexpensively.
  22. 7) Principle of expansion • It should be easy to expand with out disturbing the existing layout and production schedules 8) Principle of Versatility • Layout should be adaptable to changes in product design, sales requirement and process improvement 9) Principle of orderliness • Clean work areas with suitable equipment for removing scrap waste etc.
  23. 6. Types of layout For the purpose of production Men, Machines and Materials are required. Men work on materials with the aid of machinery and tools. For Production at least on one of them has to be moved. Production machinery can be grouped and arranged in different ways. The ways and arrangement of production machinery decides the types of layout
  24. Types of layout cont.. • Common types or methods of layout are: A. Product or line layout B. Process or functional layout C. Fixed position lay out D. Combinations (group layout) E. Cellular Manufacturing (CM) Layout
  25. The arrangement of equipment is based on the sequence of operations in the manufacture of an individual product or a group of similar products requiring the same manufacturing equipment in the same manufacturing sequence. Only one or one type of product is in operating area. The product must be standardized and manufactured in large quantities. Very popular in mass production ready made garment factory A. Product layout
  26. Plant layout example Product Layout
  27. Materials handling is automated, hence reduction in materials handling cost. Bottlenecks in production line could be avoided. Lesser manufacturing time. The layout helps in better production control. It necessitates less floor space per unit of production. WIP is reduced and investment there on is minimized. Product layout Advantages
  28. Expensive and inflexible layout. Supervision is difficult. Expansion is difficult. Breakdown of any machinery in a line could disturb the whole system. A single operator absenteeism in a line could disturb the whole system. Product layout disadvantages
  29. Similar equipment and similar operations are grouped together Useful where product is not standardized and low volume is required It has greater flexibility Advantageous when products of dissimilar types being manufactured. B. Process layout
  30. Plant layout example Process Layout
  31. Better supervision is achievable through specialization. Investments on machines are reduced as they are general purpose machines. There is greater flexibility in the production. This layout provides better use of men and machines. It is easier to handle any breakdown of machines through taking the machine to another machine station. The investment costs on machines are comparatively lower. Process layout Advantages
  32. Process layout disadvantages Movement of materials is difficult. Requires more floor space. Since the work-in-progress has to move from one place to another to look for a machine, the production time is generally high. The WIP accumulates at different places.
  33. The material and or major component ,remains in a fixed location and tools, machinery and men and other pieces of material brought to this location. Useful if the product is Extremely large or heavy ( like air craft and ship building ) and extremely low volume of output (like housing industries) High skill is demanded Very common before industrial revolution C. Fixed position layout
  34. Permits the plant to elevate skill of operators Less material movement Greater flexibility allows frequent changes in product design, product mix and production volume of demand. Layout capital investment is low. Men and machines can be utilized for numerous kinds of operations manufacturing different products. The costs of transportation for a bulky product are avoided. Fixed position layout Advantages
  35. Highly skilled man power is required Movements of machines and equipments to production centre may be time consuming Complicated fixtures may be required for positioning of jobs and tools. This may increase cost of production. Fixed position layout disadvantages
  36. • Combined layouts makes the strong points of  product,  process ,and  fixed position layouts. o Now a days pure state of any one form of layout is rare. o If the good features of all types of layout are connected a compromise solution can be obtained which will be more economical and flexible D. Combined ( Group) lay outs
  37. PRODUCTION VOLUME AND PRODUCT VARIETY DETERMINES TYPE OF LAYOUT Group layout process layout Product variety Production volume product layout Fixed Position Layouts
  38. E. CELLULAR MANUFACTURING (CM) LAYOUT In this kind of layout, the machines are generally assembled into cells which function fairly like a product layout within a process layout. Every cell in this design is shaped to produce single parts, all with common attributes, which typically means they necessitate the same machines and have similar machine settings (Ramesh Babu 2006).
  39. Plant layout example Cellular Layout
  40. E. CELLULAR MANUFACTURING (CM) LAYOUT A. Advantages: Lower WIP inventories. Reduced material handling costs. Flow time of materials is less in production planning. Improved visual control of process which enables quicker set ups. Manufacturing flexibility. Reduced machine stoppage time.
  41. 7. GENERAL FLOW PATTERNS OF PLANT LAYOUT "Flow Pattern" means the system to be adopted for the movement of raw materials, from the beginning and up to the end of manufacturing. The overall-objective of the Flow pattern is to plan for the economical movement of the raw materials throughout the plant.
  42. 7. GENERAL FLOW PATTERNS CONT.. Quite often layout design starts with the flow system and building design are modified accordingly but sometimes the flow must be adopted to existing buildings. Most common error in material flow is o Back-hauling or the back-tracking of materials, which means that once the material has passed through an operation it must maintain its direction and does not retrace its path.
  43. 7.1. FLOW SYSTEMS OF PLANT LAYOUT Based on the flow systems plant layout can be classified into two: 1. Horizontal layout and 2. Vertical layout. The horizontal flow system is adopted on a shop floor Vertical flow is adopted where material has to move in a multi-store building.
  44. 1. HORIZONTAL FLOW LINES There are five basic types of horizontal flow line: A. I-Flow or Line Flow horizontal flow lines B. L-Flow horizontal flow lines C. U-Flow horizontal flow lines D. S-Flow horizontal flow lines E. O-Flow horizontal flow lines
  45. A. I-FLOW or LINE FLOW HORIZONTAL FLOW LINES It is the simplest form of flow. In this, materials are fed at one end and components leave the line at the other end. This type is economical in space and convenient in I- shaped buildings.
  46. B. L-FLOW HORIZONTAL FLOW LINES It is similar to the I-Flow and is used where I-line cannot be accommodated in the available space Figure: L- flow horizontal flow line
  47. C. U-FLOW HORIZONTAL FLOW LINES In this, both feeding and output take place at the same end, i.e., it allows both receiving and dispatching of goods to be done at 'one side. In comparison to I or L-Flow, this method is easier for supervision. Figure: U-Flow horizontal flow lines
  48. D. S-FLOW HORIZONTAL FLOW LINES I f the production line is so long that zigzagging on the plant floor is" necessary this S-flow is adopted. This type provides efficient utilization of space and is compact enough to allow effective supervision. Figure: S-Flow horizontal flow lines
  49. E. O-FLOW HORIZONTAL FLOW LINES This type is used where process or operations are performed on- a rotary table or a rotary handling system. The components are moved from one working station to the other and when they leave the O-line, a complete set of processes or operations have been performed. The components inspected before they are moved on to a second line for an additional series of process- or operations or to an assembly line. Figure: O-Flow horizontal flow lines
  50. COMBINATIONS OF BASIC HORIZONTAL FLOW These above mentioned basic flow lines are mostly used by industries in various combinations. Figure: Combinations of basic horizontal flow
  51. I. UNIDIRECTIONAL FLOW When the material is passed from one to another without having to pass along the same path Figure: Combinations of basic horizontal flow
  52. II. RETRACTION FLOW. (REPEATED FLOW ) In this type, the flow is repeated i.e. two or more non- consecutive operations are performed on the same machine. In this flow, the available machine time is fully utilized but schedules have to allow for repeated machine setting- e.g., each time a machine is switched over from one operation to another. Figure: Retraction Flow. (Repeated flow )
  53. 2. VERTICAL FLOW LINES This type of flow is for multi-storey buildings. So that the materials handling systems and control mechanisms operate effectively, Figure: Vertical Flow lines
  54. 2. VERTICAL FLOW LINES CONT... Figure: Vertical Flow lines
  55. Reading Plant lay out and material handling (R.B Choudary) 1) Chapter Two – Introduction to plant layout
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