2. After completing this chapter, you should be able to:
1. Explain the strategic importance of process selection and the
influence it has on the organization and its supply chain.
2. Name the two main factors that influence process selection.
3. Compare the five basic processing types.
4. Explain the need for management of technology.
5. List some reasons for redesign of layouts.
Learning Objectives:
3. 6. Describe product layouts and their main advantages and
disadvantages.
7. Describe process layouts and their main advantages and
disadvantages.
8. Solve simple line-balancing problems.
9. Develop simple process layouts.
Learning Objectives:
4. Process Selection
• Process selection refers to deciding on the way production
of goods or services will be organized.
• It has major implications for capacity planning, layout of
facilities, equipment, and design of work systems.
• Forecasts, product and service design, and technological
considerations all influence capacity planning and process
selection.
5. • Different process types have different capacity ranges, and
changing them can be difficult, time consuming, and costly.
• Long-term forecasts and mission and goals are important in
developing a process strategy.
6.
7. How an organization approaches process selection is
determined by the organization’s process strategy.
Key aspects include:
• Capital Intensity: The mix of equipment and labor that will be
used by the organization.
• Process Flexibility: The degree to which the system can be
adjusted to changes in processing requirements due to such
factors as changes in product or service design, changes in
volume processed, and changes in technology.
8. Two main factors that influence process selection:
• How much variety will the process need to be able to
handle?
• How much volume will the process need to be able to
handle?
Answers to these questions will serve as a guide to
selecting an appropriate process.
Process choice is demand driven.
9. • Volume and variety are inversely related; a higher level of one
means a lower level of the other.
• The need for flexibility of personnel and equipment is directly
related to the level of variety that the process will need to
handle: The lower the variety, the less the need for flexibility,
while the higher the variety, the greater the need for flexibility.
10. • Variety means either having dedicated operations for each
different product or service, or having to get equipment
ready every time there is the need to change the product
being produced or the service being provided.
11. Process Types
There are five basic process types:
• Job Shop
• Batch
• Repetitive
• Continuous, and
• Project
12. Job Shop
• Usually operates on a relatively small scale.
• It is used when a low volume of high-variety goods or
services will be needed.
• Processing is intermittent; work includes small jobs, each
with somewhat different processing requirements.
• High flexibility using general-purpose equipment and skilled
workers are important characteristics of a job shop.
13. Batch
• Batch processing is used when a moderate volume of goods
or services is desired, and it can handle a moderate variety in
products or services.
• The equipment need not be as flexible as in a job shop, but
processing is still intermittent.
14. • The skill level of workers doesn’t need to be as high as in
a job shop because there is less variety in the jobs being
processed.
• Example of batch systems include bakeries, which make
bread, cakes, or cookies in batches.
Batch
15. Repetitive
• When higher volumes of more standardized goods or
services are needed, repetitive processing is used.
• The standardized output means only slight flexibility of
equipment is needed.
• Skill of workers is generally low.
16. • Examples of this type of system include production lines
and assembly lines.
• This type of process is sometimes referred to assembly.
Familiar products made by these systems include
automobiles, television sets, pencils, and computers.
Repetitive
17. Continuous
• When a very high volume of non-discrete, highly standardized
output is desired, a continuous system is used.
• These systems have almost no variety in output and hence,
no need for equipment flexibility.
• Workers' skill requirements can range from low to high,
depending on the complexity of the system and the expertise
workers need.
18. Continuous
• Generally, if equipment is highly specialized, worker skills can
be lower.
• Examples of non-discrete product made in continuous
systems include petroleum products, steel, sugar, flour, and
salt.
• Continuous services include air monitoring, supplying
electricity to homes and businesses, and the Internet.
19. Project
• A project is used for work that is non-routine, with a unique
set of objectives to be accomplished in a limited time frame.
• Examples range from simple to complicated, including of
activities such things as putting on a play, consulting, making
a motion picture, launching a new product or services,
publishing a book, building a dam, and building a bridge.
• Equipment flexibility and worker skills can range from low to
high.
20.
21. Product and Service Profiling
• Product or service profiling- linking key product or service
requirements to process capabilities.
• It can be used to avoid any inconsistencies by identifying
key product or service dimensions and then selecting
appropriate processes.
• Key dimensions often relate to the range of products or
services that will be processed, expected order sizes,
pricing strategies, expected frequency of schedule
changes, and order-winning requirements.
22. Sustainable Production of Goods and Services
According to the Lowell Center for Sustainable Production
(http://sustainableproduction.org),
“Sustainable Production is the creation of goods and
services using processes and systems that are: non-
polluting; conserving of energy and natural resources;
economically efficient; safe and healthful for workers,
communities, and consumers; and socially and creatively
rewarding for all working people.”
23. Lean Process Design
• One principle of particular interest here is waste reduction,
which relates to sustainability objectives.
• Lean design also focuses on variance reduction in workload
over the entire process to achieve level production and
thereby improve process flow.
• Successful lean design results in reduced inventory and floor
space; quicker response times and shorter lead times;
reduced defects, rework, and scrap; and increased
productivity.
24. • Lean process design has broad applications in seemingly
diverse areas such as health care delivery systems,
manufacturing, construction projects, and process
reengineering.
25. TECHNOLOGY
• Technological innovation refers to the discovery and
development of new or improved products, services, or
processes for producing or providing them.
• Technology refers to the application of scientific discoveries
to the development and improvement of products and
services and operations processes.
26. • High technology refers to the most advanced and
developed equipment and/or methods.
• This includes electronic data processing, the use of bar
codes and radio frequency tags to identify and track
goods, devices used to obtain point-of-sale information,
data transmission, the Internet, e-commerce, e-mail, and
more.
27. • Process technology and information technology can have a
major impact on costs, productivity, and competitiveness.
• Process technology includes methods, procedures, and
equipment used to produce goods and provide services. This
not only involves processes within an organization, it also
extends to supply chain processes.
• Information technology (IT) is the science and use of
computers and other electronic equipment to store, process,
and send information.
28. Automation
• Automation is machinery that has sensing and control devices that enable
it to operate automatically.
• Automation can range from factories that are completely automated to a
single automated operation.
• Examples range from automated teller machines (ATMs) to automated
heating and air conditioning and include automated inspection, automated
storage and retrieval systems, package sorting, mail processing, e-mail,
online banking, and E-Z pass.
29. Three Kinds of Automation
1. Fixed automation- is the least flexible.
• It uses high-cost, specialized equipment for a fixed
sequence of operations.
• Low cost and high volume are its primary advantages;
• Minimal variety and the high cost of making major changes
in either product or process are its primary limitations.
30. 2. Programmable automation- involves the use of high-cost,
general-purpose equipment controlled by a computer program that
provides both the sequence of operations and specific details about
each operation.
• This type of automation has the capability of economically
producing a fairly wide variety of low-volume products in small
batches.
• Numerically controlled (N/C) machines and some robots are
applications of programmable automation.
31. • Numerically controlled (N/C) machines are machines that
perform operations by following mathematical processing
instructions.
• Computer-aided manufacturing (CAM) refers to the use of
computers in process control, ranging from robots to automated
quality control.
• Individual machines often have their own computer; this is
referred to as computerized numerical control (CNC).
• One computer may control a number of N/C machines, which is
referred to as direct numerical control (DNC).
32. 3. Flexible automation- evolved from programmable
automation.
• It uses equipment that is more customized than that of
programmable automation.
• A key difference between the two is that flexible
automation requires significantly less changeover time.
33. • A flexible manufacturing system (FMS) is a group of
machines that include supervisory computer control,
automatic material handling, and robots or other automated
processing equipment.
• Computer-integrated manufacturing (CIM) is a system for
linking a broad range of manufacturing activities through an
integrating computer system.
34. 3D Printing
• A 3D printer is a type of industrial robot that is controlled
using computer assisted design (CAD).
• 3D printing, also known as additive manufacturing,
involves processes that create three-dimensional objects
by applying successive layers of materials to create the
objects.
35. 3D Printing
• The term 3D printing refers to a wide range of techniques
such as extrusion (the deformation of either metal or plastic
forced under pressure through a die to create a shape) and
sintering (using heat or pressure or both to form a solid
material from powder without causing it to liquefy).
36. Industrial Applications of 3D Printing
-Mass customization: Customers can create unique designs for
standard goods (e.g., cell phone cases)
-Distributed manufacturing: Local 3D printing centers that can produce
goods on demand for pickup
-Computers: Computers, motherboards, other parts
-Robots: Robots and robot parts
-Rapid prototyping: Rapid fabrication of a scale model of a physical
part or assembly
-Rapid manufacturing: Inexpensive production of one or a small
number of items
37. -Medical devices: Prosthetics
-Dental: Crowns, implants
-Pharmaceutical: Pills and medicines
-Food products: Candy, chocolate, crackers, and pasta
-Apparel: Custom-designed footwear, eyeglass frames
-Space exploration: Tools and parts can be made on the international
space station as needed instead of the cost and time needed to transport
them from earth
-Vehicles: Automotive parts, and replacement parts at repair shops;
airplane parts and spare parts; also, combine multiple parts into a single
part
-Construction: Architectural scale models
38. Drones
• Drones are remotely-controlled unmanned aircraft,
usually small.
• An important benefit is providing an “eye-in-the-sky” to
obtain visual detail in places that are hazardous to
humans or that are not readily accessible.
39. Process Strategy
• Flexible systems and equipment are often more expensive
and not as efficient as less flexible alternatives.
• In certain instances, flexibility is unnecessary because
products are in mature stages, requiring few design
changes, and there is a steady volume of output.
40. Process Strategy
• In practice, decision makers choose flexible systems for
either of two reasons:
1. Demand variety or uncertainty exists about demand.
2. The second reason can be overcome through improved
forecasting.
41. Strategic Resource Organization: Facilities Layout
• Layout refers to the configuration of departments, work
centers, and equipment, with particular emphasis on
movement of work (customers or materials) through the
system.
42. Strategic Resource Organization: Facilities Layout
• Layout decisions are important for three basic reasons:
(1) they require substantial investments of money and effort;
(2) they involve long-term commitments, which makes
mistakes difficult to overcome; and
(3) they have a significant impact on the cost and efficiency
of operations.
43. • inefficient operations (high cost, bottlenecks)
• accidents or safety hazards
• changes in the design of products or services
• introduction of new products or services
• changes in the volume of output or mix of outputs
• changes in methods or equipment
The most common reasons for redesign of layouts include:
44. • changes in environmental or other legal requirements, and
• morale problems (lack of face-to-face contact)
The most common reasons for redesign of layouts include:
45. Basic objective of layout design
-to facilitate a smooth flow of work, material, and information
through the system.
Supporting objectives generally involve the following:
1. To facilitate attainment of product or service quality.
2. To use workers and space efficiently.
3. To avoid bottlenecks.
46. 4. To minimize material handling costs.
5. To eliminate unnecessary movements of workers or
materials.
6. To minimize production time or customer service time.
7. To design for safety.
47. Four Basic Types of Layout
1. Product layouts are most conducive to repetitive
processing.
2. Process layouts are used for intermittent processing.
3. Fixed-position layouts are used when projects require
layouts.
4. Hybrid layouts are combinations of these pure types. These
include cellular layouts and flexible manufacturing systems.
48. Repetitive Processing: Product Layouts
• Product layouts are used to achieve a smooth and rapid
flow of large volumes of goods or customers through a
system.
• It is a layout that uses standardized processing
operations to achieve smooth, rapid, high-volume flow.
49. Repetitive Processing: Product Layouts
• This is made possible by highly standardized goods or
services that allow highly standardized, repetitive
processing.
• The work is divided into a series of standardized tasks,
permitting specialization of equipment and division of labor.
• It is feasible to arrange an entire layout to correspond to the
technological processing requirements of the product or
service.
50.
51. • In manufacturing environments, the lines are referred to as
production lines or assembly lines, depending on the type of
activity involved.
• A production line is a standardized layout arranged
according to a fixed sequence of production tasks.
• An assembly line is a standardized layout arranged
according to a fixed sequence of assembly tasks.
52. • In service processes, the term line may or may not be used.
• It is common to refer to a cafeteria line as such but not a car
wash, although from a conceptual standpoint, the two are
nearly identical.
53. • Examples of this type of layout are less plentiful in service
environments because processing requirements usually
exhibit too much variability to make standardization
feasible.
• Without high standardization, many of the benefits of
repetitive processing are lost.
• When lines are used, certain compromises may be made.
54. • Product layouts achieve a high degree of labor and
equipment utilization, which tends to offset their high
equipment costs.
• Operations are so closely tied to each other that the entire
system is highly vulnerable to being shut down because
of mechanical failure or high absenteeism.
55. • Preventive maintenance—periodic inspection and
replacement of worn parts or those with high failure rates—
reduces the probability of breakdowns during the
operations.
• These include maintaining an inventory of spare parts and
having repair personnel available to quickly restore
equipment to normal operation. These procedures are fairly
expensive.
56. Repetitive processing can be:
(1) machine paced (e.g., automatic car wash, automobile
assembly)
(2) worker paced (e.g., fast-food restaurants such as
McDonald’s, Burger King), or even
(3) customer paced (e.g., cafeteria line)
57. The main advantages of product layouts are:
1. A high rate of output.
2. Low unit cost due to high volume. The high cost of
specialized equipment is spread over many units.
3. Labor specialization, which reduces training costs and
time, and results in a wide span of supervision.
4. Low material-handling cost per unit. Material handling is
simplified because units follow the same sequence of
operations. Material handling is often automated.
58. 5. A high utilization of labor and equipment.
6. The establishment of routing and scheduling in the initial
design of the system. These activities do not require much
attention once the system is operating.
7. Fairly routine accounting, purchasing, and inventory control.
59. The primary disadvantages of product layouts
include the following:
1. The intensive division of labor usually creates dull,
repetitive jobs that provide little opportunity for
advancement and may lead to morale problems and to
repetitive stress injuries.
2. Poorly skilled workers may exhibit little interest in
maintaining equipment or in the quality of output.
3. The system is fairly inflexible in response to changes in the
volume of output or changes in product or process design.
60. 4. The system is highly susceptible to shutdowns caused by
equipment breakdowns or excessive absenteeism because
workstations are highly interdependent.
5. Preventive maintenance, the capacity for quick repairs,
and spare-parts inventories are necessary expenses.
6. Incentive plans tied to individual output are impractical
since they would cause variations among outputs of
individual workers, which would adversely affect the smooth
flow of work through the system.
61. U-Shaped Layouts
• A U-shaped line has a number of advantages that make it
worthy of consideration.
• One disadvantage of a long, straight line is that it interferes
with cross-travel of workers and vehicles.
• A U-shaped line is more compact; it often requires
approximately half the length of a straight production line.
• A U-shaped line permits increased communication among
workers on the line because workers are clustered, thus
facilitating teamwork.
62. • A U-shaped line minimizes material handling.
• On highly automated lines, there is less need for teamwork
and communication.
• Entry and exit points may be on opposite sides of the
building.
• Operations may need to be separated because of noise or
contamination factors.
63. • Process layouts are layouts that can handle varied
processing requirements.
• Process layouts (functional layouts) are designed to
process items or provide services that involve a variety of
processing requirements.
• Intermittent processing- means non-repetitive
processing.
Non-repetitive Processing: Process Layouts
64. • The layouts feature departments or other functional
groupings in which similar kinds of activities are performed.
• Process layouts are quite common in service
environments. Examples include hospitals, colleges and
universities, banks, auto repair shops, airlines, and public
libraries.
• Process layouts are frequently used by businesses to
create floor designs and set up equipment in a way that
maximizes efficiency.
Non-repetitive Processing: Process Layouts
65. • Workstations, machines, tools, and other equipment may be
grouped in plants with a process structure based on the
tasks they carry out.
• The overall goal of process architecture is to give
manufacturing enterprises the ability to deliver a variety of
items or services that each entails different processing
requirements.
Non-repetitive Processing: Process Layouts
66. The advantages of process layouts include the following:
1. The systems can handle a variety of processing
requirements.
2. The systems are not particularly vulnerable to equipment
failures.
3. General-purpose equipment is often less costly than the
specialized equipment used in product layouts and is easier
and less costly to maintain.
4. It is possible to use individual incentive systems.
67. The disadvantages of process layouts include the following:
1. In-process inventory costs can be high if batch processing is
used in manufacturing systems.
2. Routing and scheduling pose continual challenges.
3. Equipment utilization rates are low.
4. Material handling is slow and inefficient, and more costly per
unit than in product layouts.
68. 5. Job complexities often reduce the span of supervision and
result in higher supervisory costs than with product layouts.
6. Special attention necessary for each product or customer
(e.g., routing, scheduling, machine setups) and low volumes
result in higher unit costs than with product layouts.
7. Accounting, inventory control, and purchasing are much
more involved than with product layouts.
69. Fixed-Position Layouts
• In fixed-position layouts, the item being worked on remains
stationary, and workers, materials, and equipment are
moved about as needed.
• Almost always, the nature of the product dictates this kind of
arrangement: Weight, size, bulk, or some other factor makes
it undesirable or extremely difficult to move the product.
• Fixed-position layouts are used in large construction projects
(buildings, power plants, dams), shipbuilding, and production
of large aircraft and space mission rockets.
70. Combination Layouts
• The three basic layout types are ideal models, which may be
altered to satisfy the needs of a particular situation.
• It is not hard to find layouts that represent some combination
of these pure types.
• Ideally, a system is flexible and yet efficient, with low unit
production costs.
• Cellular manufacturing, group technology, and flexible
manufacturing systems represent efforts to move toward this
ideal.
71. Cellular Layouts
• Cellular production is a type of layout in which workstations
are grouped into what is referred to as a cell.
• Groupings are determined by the operations needed to
perform work for a set of similar items, or part families, that
require similar processing.
• The cells become, in effect, miniature versions of product
layouts.
• The cells may have no conveyorized movement of parts
between machines, or they may have a flow line connected
by a conveyor (automatic transfer).
72. • A cell layout provides a smooth flow of work through the
process with minimal transport or delay.
• Benefits frequently associated with cellular manufacturing
include minimal work in process, reduced space
requirements and lead times, productivity and quality
improvement, and increased flexibility.
• All parts follow the same route, although minor variations
(e.g., skipping an operation) are possible.
Cellular Layouts
73. Service Layouts
• As is the case with manufacturing, service layouts can often
be categorized as product, process, or fixed-position layouts.
• In a fixed-position service layout (e.g., appliance repair,
roofing, landscaping, home remodeling, copier service),
materials, labor, and equipment are brought to the customer’s
residence or office.
74. Service Layouts
• Process layouts are common in services due mainly to the
high degree of variety in customer processing requirements.
Examples include hospitals, supermarkets and department
stores, vehicle repair centers, and banks.
• If the service is organized sequentially, with all customers or
work following the same or similar sequence, as it is in a car
wash or a cafeteria line, a product layout is used.
75. Solve Simple Line-Balancing Problems
Line balancing- The process of assigning tasks to workstations
in such a way that the workstations have approximately equal
time requirements.
Cycle time- The maximum time allowed at each workstation to
complete its set of tasks on a unit.
Goal: To obtain task groupings that represent approximately
equal time requirements.
77. Sample Problem:
The tasks shown in the following precedence diagram are to
be assigned to workstations with the intent of minimizing idle
time. Management has designed an output rate of 275 units
per day. Assume 440 minutes are available per day.
a. Determine the appropriate cycle time.
b. What is the minimum number of stations possible?
78. c. Assign tasks using the “positional weight” rule: Assign tasks
with highest following times (including a task’s own time) first.
Break ties using greatest number of following tasks.
d. Compute Efficiency
79.
80.
81.
82.
83.
84.
85. Develop Simple Process Layouts
The design of process layouts requires the following information:
1. A list of departments or work centers to be arranged, their
approximate dimensions, and the dimensions of the building or
buildings that will house the departments.
2. A projection of future work flows between the various work
centers.
3. The distance between locations and the cost per unit of
distance to move loads between locations.
86. 4. The amount of money to be invested in the layout.
5. A list of any special considerations (e.g., operations that must
be close to each other or operations that must be separated).
6. The location of key utilities, access and exit points, loading
docks, and so on, in existing buildings.
88. • Layouts can also be influenced by external factors such as
the location of entrances, loading docks, elevators, windows,
and areas of reinforced flooring.
• Also important are noise levels, safety, and the size and
locations of restrooms.
• In some instances (e.g., the layouts of supermarkets, gas
stations, and fast-food chains), a sufficient number of
installations having similar characteristics justify the
development of standardized layouts.