Production

Process Production

The production process is concerned with transforming a range of inputs into those outputs that are required by the market. This involves two main sets of resources – the transforming resources, and the transformed resources. The transforming resources include the buildings, machinery, computers, and people that carry out the transforming processes. The transformed resources are the raw materials and components that are transformed into end products. Any production process involves a series of links in a production chain. At each stage value is added in the course of production. Adding value involves making a product more desirable to a consumer so that they will pay more for it. Adding value therefore is not just about manufacturing, but includes the marketing process including advertising, promotion and distribution that make the final product more desirable. 

It is very important for businesses to identify the processes that add value, so that they can enhance these processes to the ongoing benefit of the business. 

There are three main types of process: job, batch and flow production. 

Job productionJob or make complete production is the creation of single items by either one operative or ateam of operative’s e.g. the Humber Bridge or a frigate for the navy. 

It is possible for a number of identical units to be produced in parallel under job production, e.g. several frigates of a similar type. Smaller projects can also be seen as a form of job production, e.g. hand knitting a sweater, writing a book, rewiring a house, etc.

Job production is unique in the fact that the project is considered to be a single operation, which requires the complete attention of the operative before he or she passes on to the next job. A good example of job production is the work carried out by Portakabin in creating modular buildingssuch as offices, which it designs, assembles and maintains for clients. Examples from the service industries include cutting hair, and processing a customers order in a store like Argos.

The benefits of job production are:

1. The job is a unique product, which exactly matches the requirements of the customer, often from as early as the design stage. It will therefore tend to be specific to a customer’s order and not in anticipation of a sale. For example, someone doing a minimize spray paint job on a motorcycle will first discuss with a customer the sort of design he would like. A detailed sketch would then be produced on a piece of paper. Once the sketch has been approved the back of the sketch will be chalked over and traced on to the relevant piece of the motorbike. The background work is then sprayed on with an airbrush before the fine detail is painted on. The finished work is then inspected by the customer who will pay for a unique product.

2. As the work is concentrated on a specific unit, supervision and inspection of work are relatively simple.

3. Specifications for the job can change during the course of production depending upon the customer’s inspection to meet his or her changing needs. For example, when a printing firm like Polestar is asked to produce a catalogue for a grocery chain it is relatively simple to change the prices of some of the goods listed in the catalogue.

4. Working on a single unit job, coping with a variety of tasks and being part of a small team working towards the same aim would provide employees with a greater level of satisfaction. For example, aircrews working for United Airways would treat each flight as a specific job, with passengers requiring individual attention to their specific needs – e.g. for vegetarian dishes, wheelchair access to the flight, etc.

Batch production

The term batch refers to a specific group of components, which go through a production process together. As one batch finishes, the next one starts.For example on Monday, Machine A produces a type 1 engine part, on Tuesday it produces a type 2 engine part, on Wednesday a type 3 and so on. All engine parts will then go forward to the final assembly of different categories of engine parts.

Batches are continually processed through each machine before moving on to the next operation. This method is sometimes referred to as \’intermittent\’ production as different job types are held as work-in-progress between the various stages of production.

The benefits of batch production are:1. It is particularly suitable for a wide range of almost similar goods, which can

use the same machinery on different settings. For example batches of letters can be sent out to customers of an insurance company.

2. It economises upon the range of machinery needed and reduces the need for a flexible work force.

3. Units can respond quickly to customer orders by moving buffer stocks of work-in-progress or partly completed products through the final production stages.

4. It makes possible economies of scale in techniques of production, bulk purchasing and areas of minimized.

5. It makes costing easy and provides a better information service for management.

Flow production

Batch production is described as intermittent production and is minimized by irregularity. If the rest period in batch production disappeared it would then become flow production. Flow production is therefore a continuous process of parts and sub-assemblies passing on from one stage to another until completion.

Units are worked upon in each operation and then passed straight on to the next work stage without waiting for the batch to be completed. To make sure that the production line can work smoothly each operation must be of standard lengths and there should be no movements or leakages from the line, i.e. hold-ups to work-in-progress. For flow production to be successful there needs to be a continuity of demand. If demand varied, this could lead to a constant overstocking of finished goods.

Although with modern robotics it is possible to create variations in products being produced through continuous flow techniques, typically such products will be relatively minimized.Achieving a smooth flow of production requires considerable pre-production planning to make sure that raw materials are purchased and delivered just-in-time, that sufficient labour is employed and that there is continuous attention to quality throughout the production process.

The benefits of flow production are: ease of using just-in-time techniques to eliminate waste and minimize costs labour and other production costs will be reduced through detailed planning

and the use of robotics and automation

deviations  in the line can be quickly spotted through ongoing quality control techniques

as there is no rest between operations, work-in-progress levels can be kept low

the need for storage space is minimal

the physical handling of items is minimal

investment  in raw materials and parts are quickly converted into sales

Control is easy.

Assembly Production

An assembly line is a manufacturing process in which parts (usually interchangeable parts) are added to a product in a sequential manner using optimally planned logistics to create a finished product much faster than with handcrafting-type methods. The assembly line developed by Ford Motor Company between 1908 and 1915 made assembly lines famous in the following decade through the social ramifications of mass production, such as the affordability of the Ford Model T and the introduction of high wages for Ford workers. Henry Ford was the first to master the assembly line and was able to improve other aspects of industry by doing so (such as reducing labor hours required to produce a single vehicle, and increased production numbers and parts). However, the various preconditions for the development at Ford stretched far back into the 19th century, from the gradual realization of the dream of interchangeability, to the concept of reinventing workflow and job descriptions using analytical methods. Ford was the first company to build large factories around the concept. Mass production via assembly lines is widely considered to be the catalyst which initiated the modern consumer culture by making possible low unit-cost for manufactured goods. It is often said that Ford's production system was ingenious because it turned Ford's own workers into new customers. Put another way, Ford innovated its way to a lower price point and by doing so turned a huge potential market into a reality. Not only did this mean that Ford enjoyed much larger demand, but the resulting larger demand also allowed further economies of scale to be exploited, further depressing unit price, which tapped yet another portion of the demand curve. This bootstrapping quality of growth made Ford famous and set an example for other industries.

Concept

Consider the assembly of a car: assume that certain steps in the assembly line are to install the engine, install the hood, and install the wheels (in that order, with arbitrary interstitial steps); only one of these steps can be done at a time. In traditional production, only one car would be assembled at a time. If engine installation takes 20 minutes, hood installation takes 5 minutes, and wheel installation takes 10 minutes, then a car can be produced every 35 minutes.

In an assembly line, car assembly is split between several stations, all working simultaneously. When one station is finished with a car, it passes it on to the next. By having three stations, a total of three different cars can be operated on at the same time, each one at a different stage of its assembly.

After finishing its work on the first car, the engine installation crew can begin working on the second car. While the engine installation crew works on the second car, the first car can be moved to the hood station and fitted with a hood, then to the wheels station and be fitted with wheels. After the engine has been installed on the second car, the second car moves to the hood assembly. At the same time, the third car moves to the engine assembly. When the third car’s engine has been mounted, it then can be moved to the hood station; meanwhile, subsequent cars (if any) can be moved to the engine installation station.

Assuming no loss of time when moving a car from one station to another, the longest stage on the assembly line determines the throughput (20 minutes for the engine installation) so a car can be produced every 20 minutes, once the first car taking 35 minutes has been produced.

History -Before the 20th century

The assembly line concept wasn't "invented" at one time by one person. It has been independently redeveloped throughout history based on logic. Its exponentially larger development at the end of the 19th century and beginning of the 20th occurred among various people over decades, as other aspects of technology

allowed. The development of toolpath control via jigs, fixtures, and machine tools (such as the screw-cutting lathe and milling machine) during the 19th century provided the prerequisites for the modern assembly line by making interchangeable parts a practical reality. Before the 20th century, most manufactured products were made individually by hand. A single craftsman or team of craftsmen would create each part of a product. They would use their skills and tools such as files and knives to create the individual parts. They would then assemble them into the final product, making cut-and-try changes in the parts until they fit and could work together (craft production). The transition to other methods began as creativity and logic took advantage of the opportunities that the aforementioned machining developments presented. Thus, before the modern assembly line took shape, there were prototypical forms in various industries, as outlined below.

Probably the first linear and continuous assembly line of post-Renaissance times were the Portsmouth Block Mills created in 1801 by Marc Isambard Brunel (father of Isambard Kingdom Brunel), with the help of Henry Maudslay and others, for the production of blocks for the Royal Navy. This assembly line was so successful it remained in use until the 1960s, with the workshop still visible at HM Dockyard in Portsmouth, and still containing some of the original machinery.

he meatpacking industry of Chicago is believed to be one of the first industrial assembly lines (or dis-assembly lines) to be utilized in the United States starting in 1867. Workers would stand at fixed stations and a pulley system would bring the meat to each worker and they would complete one task. Henry Ford and others have written about the influence of this slaughterhouse practice on the later developments at Ford Motor Company (see below at Ford Motor Company (1908-1915)).

The Industrial Revolution in Western Europe and North America, but perhaps most especially in Great Britain and New England, led to a proliferation of manufacturing and invention. Many industries, notably textiles, firearms, clocks and watches,[2] buttons, horse-drawn vehicles, railroad cars and locomotives, sewing machines, and bicycles, saw expeditious improvement in materials handling, machining, and assembly during the 19th century, although modern concepts such as industrial engineering and logistics had not yet been named.

Ransom Olds patented the assembly line concept, which he put to work in his Olds Motor Vehicle Company factory in 1901, becoming the first company in America to mass-produce automobiles.[3] This development is often overshadowed by the independent redevelopment of assembly-line work at Ford Motor Company a few years later (see below), which introduced the ramifications of the method to a wider audience.

Sociological problems

Sociological work has explored the social alienation and boredom that many workers feel because of the repetition of doing the same specialized task all day long.[6] Because workers have to stand in the same place for hours and repeat the same motion hundreds of times per day, repetitive stress injuries are a possible pathology of occupational safety. Industrial noise also proved dangerous. When it was not too high, workers were often prohibited from talking. Charles Piaget, a skilled worker at the LIP factory, recalled that beside being prohibited from speaking, the semi-skilled workers had only 25 centimeters in which to move. Industrial ergonomics later tried to minimize physical trauma.

Job production

Job production involves firms producing items that meet the specific requirements of the customer. Often these are one-off, unique items such as those made by an architect or wedding dressmaker. For an architect, each building or structure that he designs will be different and tailored to the needs of each individual client.

With job production, a single worker or group of workers handles the complete task. Jobs can be on a small-scale involving little or no technology. However, jobs can also be complex requiring lots of technology.

With low technology jobs, production is simple and it is relatively easy to get hold of the skills and equipment required. Good examples of the job method include:

Hairdressers

Tailoring

Painting and decorating

Plumbing and heating repairs in the home

High technology jobs are much more complex and difficult. These jobs need to be very well project-managed and require highly qualified and skilled workers. Examples of high technology / complex jobs include:

Film production

Large construction projects (e.g. the Millennium Dome)

Installing new transport systems (e.g. trams in Sheffield and Manchester)

Advantages

The advantage of job production is that each item can be altered for the specific customer and this provides genuine marketing benefits. A business is likely to be able to ‘add value’ to the products and possibly create a unique selling point (USP), both of which should enable it to sell at high prices.

Disadvantages

Whether it is based on low or high technology, Job production is an expensive process as it is labour intensive (uses more workers compared to machines). This raises costs to firms as the payment of wages and salaries is more expensive than the costs of running machines.

Mass Production

Mass production (also called flow production, repetitive flow production, series production, or serial production) is the production of large amounts of standardized products, including and especially on assembly lines. The concepts of mass production are applied to various kinds of products, from fluids and particulates handled in bulk (such as food, fuel, chemicals, and mined minerals) to

discrete solid parts (such as fasteners) to assemblies of such parts (such as household appliances and automobiles).

Advantages and disadvantages

The economies of mass production come from several sources. The primary cause is a reduction of nonproductive effort of all types. In craft production, the craftsman must bustle about a shop, getting parts and assembling them. He must locate and use many tools many times for varying tasks. In mass production, each worker repeats one or a few related tasks that use the same tool to perform identical or near-identical operations on a stream of products. The exact tool and parts are always at hand, having been moved down the assembly line consecutively. The worker spends little or no time retrieving and/or preparing materials and tools, and so the time taken to manufacture a product using mass production is shorter than when using traditional methods.

The probability of human error and variation is also reduced, as tasks are predominantly carried out by machinery. A reduction in labour costs, as well as an increased rate of production, enables a company to produce a larger quantity of one product at a lower cost than using traditional, non-linear methods.

However, mass production is inflexible because it is difficult to alter a design or production process after a production line is implemented. Also, all products produced on one production line will be identical or very similar, and introducing variety to satisfy individual tastes is not easy. However, some variety can be achieved by applying different finishes and decorations at the end of the production line if necessary.

Machine tools and interchangeable parts

The material basis for mass production was laid by the development of the machine-tool industry--that is, the making of machines to make machines. Though some basic devices such as the woodworking lathe had existed for centuries, their translation into industrial machine tools capable of cutting and shaping hard metals to precise tolerances was brought about by a series of 19th-century innovators, first in Britain and later in the United States. With precision equipment, large numbers of identical parts could be produced at low cost and with a small work force.

The system of manufacture involving production of many identical parts and their assembly into finished products came to be called the American System, because it achieved its fullest maturity in the United States. Although Eli Whitney has been given credit for this development, his ideas had appeared earlier in Sweden, France, and Britain and were being practiced in arms factories in the United States. During the years 1802-08, for example, the French émigré engineer Marc Brunel, while working for the British Admiralty in the Portsmouth Dockyard, devised a process for producing wooden pulley blocks by sequential machine operations. Ten men, in place of 110 needed previously, were able to make 160,000 pulley blocks per year. British manufacturers, however, ignored Brunel's ideas, and it was not until London's Crystal Palace exhibition of 1851 that British engineers, viewing exhibits of machines used in the United States to produce interchangeable parts, began to apply the system. By the third quarter of the 19th century, the American System was employed in making small arms, clocks, textile machinery, sewing machines, and a host of other industrial products.

The assembly line

Though prototypes of the assembly line can be traced to antiquity, the true ancestor of this industrial technique was the 19th-century meat-packing industry in Cincinnati, Ohio, and in Chicago, where overhead trolleys were employed to convey carcasses from worker to worker. When these trolleys were connected with chains and power was used to move the carcasses past the workers at a steady pace, they formed a true assembly line (or in effect a "disassembly" line in the case of meat cutters). Stationary workers concentrated on one task, performing it at a pace dictated by the machine, minimizing unnecessary movement, and dramatically increasing productivity.

Drawing upon observations of the meat-packing industry, the American automobile manufacturer Henry Ford designed an assembly line that began operation in 1913. The result was a remarkable reduction of manufacturing time for magneto flywheels from 20 minutes to five minutes. This success stimulated Ford to apply the technique to chassis assembly. Under the old system, by which parts were carried to a stationary assembly point, 12 1/2 man-hours were required for each chassis. Using a rope to pull the chassis past stockpiles of components, Ford cut labour time to six man-hours. With improvements--a chain drive to power

assembly-line movement, stationary locations for the workmen, and work stations designed for convenience and comfort--assembly time fell to 93 man-minutes by the end of April 1914. Ford's methods drastically reduced the price of a private automobile, bringing it within the reach of the common man. (see also Index: automotive industry ) Ford's spectacular feats forced both his competitors and his parts suppliers to initiate his technique, and the assembly line spread through a large part of U.S. industry, bringing dramatic gains in productivity and causing skilled workers to be replaced with low-cost unskilled labour. Because the pace of the assembly line was dictated by machines, the temptation arose to accelerate the machines, forcing the workers to keep up. Such speedups became a serious point of contention between labour and management, while the dull, repetitive nature of many assembly-line jobs bored employees, reducing their output.

Effects on the organization of work.

The development of mass production transformed the organization of work in three important ways. First, tasks were minutely subdivided and performed by unskilled workers, or at least semiskilled workers, since much of the skill was built into the machine. Second, manufacturing concerns grew to such size that a large hierarchy of supervisors and managers became necessary. Third, the increasing complexity of operations required employment of a large management staff of accountants, engineers, chemists, and, later, social psychologists, in addition to a large distribution and sales force. Mass production also heightened the trend toward an international division of labour. The huge new factories often needed raw materials from abroad, while saturation of national markets led to a search for customers overseas. Thus, some countries became exporters of raw materials and importers of finished goods, while others did the reverse.

In the 1970s and '80s some countries, particularly in Asia and South America, that had hitherto been largely agricultural and that had imported manufactured goods began industrializing. The skills needed by workers on assembly-line tasks were easily acquired, and standards of living in these developing countries were so low that wages could be kept below those of the already industrialized nations. Many large manufacturers in the United States and elsewhere therefore began

"outsourcing"--that is, having parts made or whole products assembled in developing nations. Consequently, those countries are rapidly becoming integrated into the world economic community.

Batch production

Batch production is the manufacturing technique of creating a group of components at a workstation before moving the group to the next step in production.

Batch production is common in bakeries and in the manufacture of sports shoes, pharmaceutical ingredients, inks, paints and adhesives.

In the manufacture of inks and paints, a technique called a colour-run is used. A colour-run is where one manufactures the lightest colour first, such as light yellow followed by the next increasingly darker colour such as orange, then red and so on until reaching black and then starts over again.

This minimizes the cleanup and reconfiguring of the machinery between each batch. White (by which is meant opaque paint, not transparent ink) is the only colour that cannot be used in a colour-run because a small amount of white pigment can adversely affect the medium colours.

As businesses grow and production volumes increase, the production process is often changed to a “batch method”. Batch methods require that a group of items move through the production process together, a stage at a time.

For example when a bakery bakes loaves of wholemeal bread, a large ball of wholemeal dough will be split into several loaves which will be spread out together on a large baking tray. The loaves on the tray will then together be cooked, wrapped and dispatched to shelves, before the bakery starts on a separate batch of, for example, crusty white bread. Note that each loaf is identical within a batch but that loaves can vary from batch to batch.

Batch production is a very common method of organising manufacture. Good examples include:

Production of electronic instruments Fish and chip shops

Paint and wallpaper manufacturers

Cereal farming

Advantages and Disadvantages

There are several advantages of batch production; it can reduce initial capital outlay because a single production line can be used to produce several products.

As shown in the example, batch production can be useful for small businesses who cannot afford to run continuous production lines.

If a retailer buys a batch of a product that does not sell, then the producer can cease production without having to sustain huge losses.

Batch production is also useful for a factory that makes seasonal items, products for which it is difficult to forecast demand, a trial run for production, or products that have a high profit margin.

Batch production also has disadvantages. There are inefficiencies associated with batch production as equipment must be stopped, re-configured, and its output tested before the next batch can be produced.

LAYOUT

In manufacturing, facility layout consists of configuring the plant site with lines, buildings, major facilities, work areas, aisles, and other pertinent features such as department boundaries. While facility layout for services may be similar to that for manufacturing, it also may be somewhat different—as is the case with offices, retailers, and warehouses. Because of its relative permanence, facility layout probably is one of the most crucial elements affecting efficiency. An efficient layout can reduce unnecessary material handling, help to keep costs low, and maintain product flow through the facility.

Firms in the upper left-hand corner of the product-process matrix have a process structure known as a jumbled flow or a disconnected or intermittent line flow. Upper-left firms generally have a process layout. Firms in the lower right-hand corner of the product-process matrix can have a line or continuous flow. Firms in the lower-right part of the matrix generally have a product layout. Other types of layouts include fixed-position, combination, cellular, and certain types of service layouts.

PROCESS LAYOUT

Process layouts are found primarily in job shops, or firms that produce customized, low-volume products that may require different processing requirements and sequences of operations. Process layouts are facility configurations in which operations of a similar nature or function are grouped together. As such, they occasionally are referred to as functional layouts. Their purpose is to process goods or provide services that involve a variety of processing requirements. A manufacturing example would be a machine shop. A machine shop generally has separate departments where general-purpose machines are grouped together by function (e.g., milling, grinding, drilling, hydraulic presses, and lathes). Therefore, facilities that are configured according to individual functions or processes have a process layout. This type of layout gives the firm the flexibility needed to handle a variety of routes and process requirements. Services that utilize process layouts include hospitals, banks, auto repair, libraries, and universities.

Advantages of process layouts include:

Flexibility. The firm has the ability to handle a variety of processing requirements.

Cost. Sometimes, the general-purpose equipment utilized may be less costly to purchase and less costly and easier to maintain than specialized equipment.

Motivation. Employees in this type of layout will probably be able to perform a variety of tasks on multiple machines, as opposed to the boredom of performing a repetitive task on an assembly line. A process layout also allows the employer to use some type of individual incentive system.

System protection. Since there are multiple machines available, process layouts are not particularly vulnerable to equipment failures.

Disadvantages of process layouts include:

Utilization. Equipment utilization rates in process layout are frequently very low, because machine usage is dependent upon a variety of output requirements.

Cost. If batch processing is used, in-process inventory costs could be high. Lower volume means higher per-unit costs. More specialized attention is necessary for both products and customers. Setups are more frequent, hence higher setup costs. Material handling is slower and more inefficient. The

span of supervision is small due to job complexities (routing, setups, etc.), so supervisory costs are higher. Additionally, in this type of layout accounting, inventory control, and purchasing usually are highly involved.

Confusion. Constantly changing schedules and routings make juggling process requirements more difficult.

PRODUCT LAYOUT

Product layouts are found in flow shops (repetitive assembly and process or continuous flow industries). Flow shops produce high-volume, highly standardized products that require highly standardized, repetitive processes. In a product layout, resources are arranged sequentially, based on the routing of the products. In theory, this sequential layout allows the entire process to be laid out in a straight line, which at times may be totally dedicated to the production of only one product or product version. The flow of the line can then be subdivided so that labor and equipment are utilized smoothly throughout the operation.

Two types of lines are used in product layouts: paced and unpaced. Paced lines can use some sort of conveyor that moves output along at a continuous rate so that workers can perform operations on the product as it goes by. For longer operating times, the worker may have to walk alongside the work as it moves until he or she is finished and can walk back to the workstation to begin working on another part (this essentially is how automobile manufacturing works).

On an unpaced line, workers build up queues between workstations to allow a variable work pace. However, this type of line does not work well with large, bulky products because too much storage space may be required. Also, it is difficult to balance an extreme variety of output rates without significant idle time. A technique known as assembly-line balancing can be used to group the individual tasks performed into workstations so that there will be a reasonable balance of work among the workstations.

Product layout efficiency is often enhanced through the use of line balancing. Line balancing is the assignment of tasks to workstations in such a way that workstations have approximately equal time requirements. This minimizes the amount of time that some workstations are idle, due to waiting on parts from an upstream process or to avoid building up an inventory queue in front of a downstream process.

Advantages of product layouts include:

Output. Product layouts can generate a large volume of products in a short time.

Cost. Unit cost is low as a result of the high volume. Labor specialization results in reduced training time and cost. A wider span of supervision also reduces labor costs. Accounting, purchasing, and inventory control are routine. Because routing is fixed, less attention is required.

Utilization. There is a high degree of labor and equipment utilization.

Disadvantages of product layouts include:

Motivation. The system's inherent division of labor can result in dull, repetitive jobs that can prove to be quite stressful. Also, assembly-line layouts make it very hard to administer individual incentive plans.

Flexibility. Product layouts are inflexible and cannot easily respond to required system changes—especially changes in product or process design.

System protection. The system is at risk from equipment breakdown, absenteeism, and downtime due to preventive maintenance.

FIXED-POSITION LAYOUT

A fixed-position layout is appropriate for a product that is too large or too heavy to move. For example, battleships are not produced on an assembly line. For services, other reasons may dictate the fixed position (e.g., a hospital operating room where doctors, nurses, and medical equipment are brought to the patient). Other fixed-position layout examples include construction (e.g., buildings, dams, and electric or nuclear power plants), shipbuilding, aircraft, aerospace, farming, drilling for oil, home repair, and automated car washes. In order to make this work, required resources must be portable so that they can be taken to the job for "on the spot" performance.

Due to the nature of the product, the user has little choice in the use of a fixed-position layout. Disadvantages include:

Space. For many fixed-position layouts, the work area may be crowded so that little storage space is available. This also can cause material handling problems.

Administration. Oftentimes, the administrative burden is higher for fixed-position layouts. The span of control can be narrow, and coordination difficult.

COMBINATION LAYOUTS

Many situations call for a mixture of the three main layout types. These mixtures are commonly called combination or hybrid layouts. For example, one firm may utilize a process layout for the majority of its process along with an assembly in one area. Alternatively, a firm may utilize a fixed-position layout for the assembly of its final product, but use assembly lines to produce the components and subassemblies that make up the final product (e.g., aircraft).

CELLULAR LAYOUT

Cellular manufacturing is a type of layout where machines are grouped according to the process requirements for a set of similar items (part families) that require similar processing. These groups are called cells. Therefore, a cellular layout is an equipment layout configured to support cellular manufacturing.

Processes are grouped into cells using a technique known as group technology (GT). Group technology involves identifying parts with similar design characteristics (size, shape, and function) and similar process characteristics (type of processing required, available machinery that performs this type of process, and processing sequence).

Workers in cellular layouts are cross-trained so that they can operate all the equipment within the cell and take responsibility for its output. Sometimes the cells feed into an assembly line that produces the final product. In some cases a cell is formed by dedicating certain equipment to the production of a family of parts without actually moving the equipment into a physical cell (these are called virtual or nominal cells). In this way, the firm avoids the burden of rearranging its current layout. However, physical cells are more common.

An automated version of cellular manufacturing is the flexible manufacturing system (FMS). With an FMS, a computer controls the transfer of parts to the

various processes, enabling manufacturers to achieve some of the benefits of product layouts while maintaining the flexibility of small batch production.

Some of the advantages of cellular manufacturing include:

Cost. Cellular manufacturing provides for faster processing time, less material handling, less work-in-process inventory, and reduced setup time, all of which reduce costs.

Flexibility. Cellular manufacturing allows for the production of small batches, which provides some degree of increased flexibility. This aspect is greatly enhanced with FMSs.

Motivation. Since workers are cross-trained to run every machine in the cell, boredom is less of a factor. Also, since workers are responsible for their cells' output, more autonomy and job ownership is present.

OTHER LAYOUTS

In addition to the aforementioned layouts, there are others that are more appropriate for use in service organizations. These include warehouse/storage layouts, retail layouts, and office layouts.

With warehouse/storage layouts, order frequency is a key factor. Items that are ordered frequently should be placed close together near the entrance of the facility, while those ordered less frequently remain in the rear of the facility. Pareto analysis is an excellent method for determining which items to place near the entrance. Since 20 percent of the items typically represent 80 percent of the items ordered, it is not difficult to determine which 20 percent to place in the most convenient location. In this way, order picking is made more efficient.

While layout design is much simpler for small retail establishments (shoe repair, dry cleaner, etc.), retail stores, unlike manufacturers, must take into consideration the presence of customers and the accompanying opportunities to influence sales and customer attitudes. For example, supermarkets place dairy products near the rear of the store so that customers who run into the store for a quick gallon of milk must travel through other sections of the store. This increases the chance of the customer seeing an item of interest and making an impulse buy. Additionally, expensive items such as meat are often placed so that the customer will see them frequently (e.g., pass them at the end of each aisle). Retail chains are able to take advantage of standardized layouts, which give the customer more familiarity with the store when shopping in a new location.

Office layouts must be configured so that the physical transfer of information (paperwork) is optimized. Communication also can be enhanced through the use of low-rise partitions and glass walls.

A number of changes taking in place in manufacturing have had a direct effect on facility layout. One apparent manufacturing trend is to build smaller and more compact facilities with more automation and robotics. In these situations, machines need to be placed closer to each other in order to reduce material handling. Another trend is an increase in automated material handling systems, including automated storage and retrieval systems (AS/AR) and automated guided vehicles (AGVs). There also is movement toward the use of U-shaped lines, which allow workers, material handlers, and supervisors to see the entire line easily and travel efficiently between workstations. So that the view is not obstructed, fewer walls and partitions are incorporated into the layout. Finally, thanks to lean manufacturing and just-in-time production, less space is needed for inventory storage throughout the layout.