Maintenance and Quality Management

Module V

Operations Management Notes ( Pvt Circulation Only) Compiled by Santhosh.S, Associate Professor, SCMS Cochin

Module V: Maintenance Management Function Types of Maintenance Total ProductiveMaintenance (TPM). Statistical Quality Control (SQC). Cost of Quality (COQ). ISO 9000 certification. Total Quality Management. MAINTENANCE MANAGEMENT

Maintenance Management is planning, organizing and controlling maintenance activities such that the overall maintenance cost is minimum.

Benefits of Maintenance Management

Objectives of Maintenance

1. To prevent Breakdown

2. Ensure operational safety

3. Ensure Operational Efficiency

4. Reduce cost

5. Reduce Idle hours- Component Malfunction

6. Prevent rapid wear of components

Benefits of

Maintenance

Management

The production capacity of the

facility is almost unaffected due

to well maintained machines and

thus, lesser breakdowns.

Production cost can be kept

minimum as lesser breakdowns of

equipment means less opportunities

for workers being idle

Quality of products and services

remains unaffected due to proper

maintenance of equipment, thus

reducing the possibility of

variation in the output

Life of facilities and equipment

increases due to proper

maintenance

The delivery schedules of

customers are not disrupted due to

unexpected breakdowns, leading

to customer satisfactions

The Possibility of sudden

breakdowns of equipment

resulting in safety hazards to

workers is minimized.

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7. Eliminate defects.

Maintenance Functions

Maintenance functions can be grouped in two categories Basic functions and Composite

functions

Basic Functions

1. Replace To remove an unserviceable item and install a serviceable counterpart in its

place\

2. Repair- The application of maintenance services including fault location troubleshooting,

removal installation, and disassembly/ Assembly procedures, and maintenance actions to

identify troubles and restore serviceability to an item by appropriate corrections.

3. Overhaul- That maintenance effort prescribed to restore an item to a completely

serviceable/operational condition.

4. Rebuild- It consists of those services/actions necessary for the restoration of

unserviceable equipment to a like new condition in accordance with original

manufacturing standards.

5. Service/ Lubricate- Operations required periodically to keep an item in proper operating

condition ie to clean, to preserve, to drain, to paint or replenish fuel, lubricants, chemical

fluids or gases.

6. Inspect/ check- To determine the serviceability of an item by comparing its physical,

mechanical, and /or electrical characteristics with prescribed standards.

7. Test To verify serviceability by measuring the mechanical or electrical characteristics

of an item and compare those characteristics with prescribed standards.

8. Adjust- To maintain, within prescribed limit, by bringing into proper or exact position, or

by setting the operating characteristics to specified parameters.

9. Align- To adjust specified variable elements of an item to bring about optimum or desired

performance.

10. Calibrate- To determine and cause corrections to be made or to be adjusted on

instruments or test, measuring and diagnostic equipment used in precision measurement,

using a certified standard instrument.

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11. Measure The act or process of ascertaining the extend, dimension or quantity of

something. Like the extend of wear and tear, elongation,

12. Winding- Provide a symmetrically laid electrical conduction path in any device like the

motor winding.

13. Install- The act of seating or fixing into position an item, part or module in manner to

allow proper functioning of an equipment or system.

Composite functions

1. Protecting building, structures, plants, and factories.

2. Reducing downtime and increasing availability.

3. Analyze failures and arrange their elimination.

4. Forecast maintenance spares, tools consumables etc

5. Economy in maintenance department

6. Ensure safety in installations.

7. Cost reduction and cost control.

8. Prepare maintenance budgets.

9. Waste reduction and waste recovery.

10. Improving technical communication

11. Training of maintenance personnel on related job.

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3. Could lead to reduction in the reliability of the machine as breakdown maintenance concentrated on the failure and its obvious reason rather than the root cause.

Preventive Maintenance

Maintenance work is done at predetermined time or on the basis of other criteria like

Fixed no. of cycles of operations Usage hours Cumulative output

The basis assumption is that the failure of equipment is dependent on time in a predictable way.

ADVANTAGES

1. Less unexpected shutdowns

2. Less consequential secondary damages ( damages caused on other components due to

failure of an equipment)

3. Better Utilization of manpower and maintenance resources ( as the activity can be

properly planned in advance)

4. Reduced Overtime costs

5. Better equipment condition hence less rejects and reworks

6. Improved safety and quality

DISADVANTAGES

1. Does not ensure full protection against unexpected shutdowns. In spite of regular

preventive maintenance unexpected shutdowns can occur.

2. Some maintenance may not be necessary.

3. Periodic maintenance may increase running in failures. Running in failures are failures

that occur when new components are put in operation for the first time. The components

replaced during preventive maintenance can fail prematurely thus defeating the very

purpose of preventive maintenance.

Predictive Maintenance

1. Also known as condition based Maintenance. The condition of the equipment is

monitored regularly and equipment is taken for maintenance if the condition indicates a

likely hood of equipment failure.

2. Equipment maintained when measurements indicate incipient failure.

Condition Monitoring

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1. Condition may be determined continuously or at regular intervals.

2. Condition could be vibration, debris analysis, temperature, quality of product etc.

ADVANTAGES

Fairly effective protection from unexpected shutdowns.

Equipment rarely stopped for unnecessary maintenance.

Could help in reducing the stress on the machinery in case of an incipient failure

Could be used to check the quality of maintenance.

DISADVANTAGE

Has certain amount of subjectivity which could lead to the risk of planning maintenance

too early or too late.

Is justified only when the benefits are larger than the cost of monitoring. ( Monitoring

instruments, Analyses etc.)

TOTAL PRODUCTIVE MAINTENANCE

TPM is a philosophy of continuous improvement that creates a sense of ownership in the

operators and other connected persons for the machines. It combines the traditional practices of

preventive and predictive maintenance with total quality control and total employee

participation/ involvement to create a culture where operators develop ownership of their

equipment and become full partners with maintenance, engineering and management etc to

ensure that equipments operate properly everyday at required time.

The three different words of TPM can be defined as following

Total

1. All employees are involved in it.

2. It aims to eliminate all breakdowns, defects and accidents.

Productive

1. Many actions are performed while production goes on.

2. Troubles for production are minimized, if not eliminated.

Maintenance

1. Check Clean, lubricate and repair.

2. Keep Machine in good condition.

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The concept of Productive Maintenance was first introduced by M/s Nihon Denso Co. Japan in

the year 1971 and was subsequently promoted to national level in Japan in 1983, by Japanese

Institute of Plant maintenance.

Features / Principles of TPM

Some of the features / principles considered for successful TPM are as following

Increase Overall Equipment Effectiveness ( OEE) The operator is the best condition monitor. Involves all departments such as operations, maintenance, connected planning groups,

material management, quality, finance and administration.

Involves the participation (up-to required level) of members of all groups from management level to shop-floor worker level.

Provides training to upgrade operation and maintenance skills. Generally promotes small autonomous group concept for better motivation and

coordination:

Establishes a total system of completer maintenance and upkeep of the equipments, generally covering the entire plant life cycle; etc.

Components or pillars of TPM

Following are the basic eight basic components or pillars of TPM

1. Autonomous Maintenance ( Jishu Hozen)

2. Equipment and process improvement, using KAIZEN

3. Planned Maintenance

4. Early management of new equipment

5. Process quality Management and Quality Maintenance

6. Education and Training

7. TPM in administrative and support departments

8. Safety and environmental Management

1. Autonomous Maintenance

It promotes small autonomous group concepts, involving operation, maintenance and all

connected disciplines to required degree. In order to increase the operators knowledge,

participation and responsibility for their equipment, following steps are taken-

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1. Train the operators to close the gap between them and the maintenance staff making it

easier for both to work as one team( flexible operator)

2. Change the equipment so the operator can identify any abnormal conditions and measure

deterioration before it affects the process or leads to a failure.

3. Operator to perform initial cleaning and inspection: take counter measures for the causes

and effects of dirt and dust; prove covers and other protective or self cleaning devices.

4. Other counter measures- In-accessible regions had to be reached easily. Instead of

opening a door for inspecting the machine, acrylic sheets can be used.

5. Establish cleaning and lubrication standards and operator to carryout minor lubrication

and monitor lubrication gadgets.

6. Eliminating the defects at source through active employee participation.

7. Autonomous inspection, including continuous monitoring and changing frequencies and

points and items for cleaning and inspection, depending on the results and experience.

8. Work environment is modified such that there is no difficulty or time loss in getting any

item.

9. Autonomous management- OEE (Overall Equipment efficiency) and OPE (Overall

production efficiency) and other PM targets must be achieved by continuous

improvement through Kaizen, PDCA( Plan, Do , Check, Act) cycle must be implemented

for Kaizen.

2. Equipment and Process improvement, Using Kaizen

The objective of this component (pillar) is to maximize efficiency by eliminating waste and

manufacturing losses. Basically kaizen is for small improvements, but is carried out on a

continual basis and involve all people in the organization. Kaizen is the opposite of big

spectacular innovation. It requires little or no investment. The principle behind is that a very

large number of small improvements are more effective in an organizational environment than a

few improvements of large value.

TPM identifies following major sources of losses and then works systematically to eliminate

them.

A) Losses that impede equipment efficiency( Equipment losses) a. Downtime losses

i. Equipment failure/ breakdowns

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ii. Setup and adjustments

iii. Scheduled downtime loss

iv. Consumable breakage/ Change loss ( cutting blade loss etc)

b. Speed loss i. Minor stopping / idling

ii. Reduced speed

c. Quality loss

i. Process errors

ii. Rework / Scraps

B) Losses that impede human efficiency ( Manpower loss) i. Cleaning and checking

ii. Waiting for instructions

iii. Waiting for materials

iv. Waiting quality confirmation

v. Measurement and adjustment loss

C) Losses that impede effective use of production resources ( Material loss) i. Material Yield loss

ii. Energy Loss

iii. Consumable material loss( Die, Jig, and tool breakage loss etc.)

3. Planned Maintenance

Objective of this component (Pillar) is to establish preventative, predictive maintenance systems

for equipment and tooling. Natural life cycle of individual machine elements must be achieved

for trouble free working, producing defect-free products for total customer satisfaction, by

planned maintenance. (Corrective, preventive, predictive, maintenance prevention) Correct

operation, correct set-up, proper cleaning, proper lubrication, necessary retightening, feedback

and repair of minor defects and quality spares etc are specifically taken care of.

4 Early Management of new equipment

The objective of this component is

1. To establish a system to shorten/ minimize the time for new equipment or product

development.

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2. System shortens the start-up, commissioning and stabilization time for quality and

efficiency.

3. New equipment needs to be

a. Easy to operate

b. Easy to clean

c. Reliable and easy to maintain

d. Have quick set-up times

e. Have easily visual and approachable built-in test equipment and condition

monitoring equipment.

f. Operate at lowest life cycle cost.

5. Process Quality Management and Quality Maintenance

This component (Pillar) calls for a process for controlling the condition of equipment and

machineries that affect variability in product quality and drives defect free products. Its

objective is to set and maintain conditions of equipments to accomplish zero defects as

the quality rate of any product has a direct correlation with

Material condition Equipment condition and precision Production methods Process parameters.

6. Education and Training

TPM is a continuous learning process. It is aimed to have multi-skilled revitalized employees

whose morale is high and who is eager to come to work and perform all required functions

effectively and independently. Education and training is given to operators/workmen to upgrade

their skill. There are following four knowledge stages of a workman about a job

Stage 1 Do not know

Stage 2 Know the theory, but cannot do

Stage 3- Can do the job but cannot teach

Stage 4 Can do the job and can teach also.

The prerequisite of for this component (Pillar) is checking the present status of education,

training and skills of the available men and setting priorities and policies for improvement.

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7. TPM in administrative and support departments (Office TPM)

Administrative and support departments can be seen as process plants whose principal taks are to

collect, process and distribute information. The aim of this component is to improve

productivity, efficiency in the administrative and support functions and identify and eliminate

losses. This includes analyzing processes and procedures towards increased office automation.

Office TPM addresses many major losses, few of those are

1. Processing loss

2. Cost losses in areas like procurement, accounts, marketing , sales leading to high

inventories

3. Communication loss

4. Idle loss and set up loss

5. Office equipment breakdown

6. Communication channel breakdown

7. Time spent on retrieval of information

8. Non availability of correct on line stock status.

9. Customer complaints due to logistics.

10. Expenses on emergency dispatch/ purchases etc.

8. Safety and Environmental Management

Assuring safety and preventing adverse environmental impacts are important priorities of any

TPM effort. In this area focus is on to create a safe workplace and a surrounding area that is not

damaged by the processes or procedures. This component (Pillar) will play an active role in each

of the other pillar on a regular basis.

Aims and Targets

Zero Accidents, Zero health hazard/ damage and Zero fire etc.

The 5-S concept (Sort, Clean (Seiton), Set in order, standardize, and sustain/Progress)can also be

considered as an important component of TPM

Benefits of TPM

1. Increased equipment productivity

2. Increased plant capacity

3. Reduced equipment downtime

4. Lower maintenance and production cost

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5. Immediate attention of smaller problems to prevent its aggravation.

6. Approaching zero equipment caused defects.

7. Reduced inventory levels and inventory carrying costs in all parts of the supply chain.

8. Better utilization of work area and improved productivity of employees

9. Enhanced job-satisfaction and

10. Increased Return on Investment.

QUALITY MANAGEMENT

Quality

Statistical Quality Control-

Statistical quality control is the set of statistical tools used by Quality professional. It can be

classified broadly into 3 categories

1. Descriptive Statistics Are used to describe quality characteristics and their relationships. Included are statistics such as mean, standard deviation, range and a

measure of distribution of data.

2. Statistical Process Control (SPC) Involves inspecting a random sample of the output

from a process and deciding whether the process is producing products that fall within a

predetermined range. SPC answers the question whether the process is functioning

properly or not.

3. Acceptance sampling Is the process of inspecting randomly inspecting a sample of

goods from a lot and deciding whether to accept or reject the lot based on the result.

Acceptance sampling determines whether a batch of goods should be accepted or

rejected.

The tools in each of these categories provide different types of information for use in analyzing

quality. Descriptive statistics are used to describe certain quality characteristics, such as the

central tendency and variability of observed data. Although descriptions of certain characteristics

are helpful, they are not enough to help us evaluate whether there is a problem with quality.

Acceptance sampling can help us do this. Acceptance sampling helps us decide whether

desirable quality has been achieved for a batch of products, and whether to accept or reject the

items produced. Although this information is helpful in making the quality acceptance decision

after the product has been produced, it does not help us identify and catch a quality problem

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during the production process. For this we need tools in the statistical process control (SPC)

category.

All three of these statistical quality control categories are helpful in measuring and evaluating the

quality of products or services. However, statistical process control (SPC) tools are used most

frequently because they identify quality problems during the production process. For this reason,

we will devote most of the chapter to this category of tools. The quality control tools we will be

learning about do not only measure the value of a quality characteristic. They also help us

identify a change or variation in some quality characteristic of the product or process.

Variations from predetermined standards lead to quality issues. Two kinds of causes lead to

variations: Natural or random causes of variations and Assignable causes of variations. Natural

or random causes are neither identifiable nor explainable. They occur purely by chance. The

second type of causes of variations can be precisely identified and eliminated. These are called

the Assignable causes of Variations. Examples of this type of variations are poor quality in raw

materials, an employee who needs training, a machine that needs repair. In each of these

examples the problem can be identified and corrected.

Variables and attributes: The measures used by operations to describe quality characteristics

are of two types: variables and attributes. Variable measures are those that can be measured on a

continuously variable scale (for example, length, diameter, weight or time). Attributes are those

which are assessed by judgment and are dichotomous, ie. have two states (for example, right or

wrong, works or does not work, looks OK or not OK- deal or no-deal !).

Table below categorizes some of the measures which might be used for the quality

characteristics of a car.

Some variable and attributes of a car

Quality characteristic Variable Attribute

Functionality Acceleration and braking

characteristics from test bed

Is the ride quality satisfactory?

Appearance Number of blemishes visible

on car

Is the colour to specification

Reliability Average time between faults Is the reliability satisfactory

Durability Life of the car- x years Is the useful life as predicted

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Quality characteristic Variable Attribute

Recovery Time from fault discovered to

fault repaired

Is the serviceability of the car

acceptable

Contact Level of help provided by

sales staff (1 to 5 scale)

Did customers feel well served

(yes or no)?

DESCRIPTIVE STATISTICS

Descriptive statistics can be helpful in describing certain characteristics of a product and a

process. The most important descriptive statistics are measures of central tendency such as the

mean, measures of variability such as the standard deviation and range, and measures of the

distribution of data.

STATISTICAL PROCESS CONTROL Statistical process control methods extend the use of descriptive statistics to monitor the quality

of the product and process. There are common and assignable causes of variation in the

production of every product. Using statistical process control we want to determine the amount

of variation that is common or normal. Then we monitor the production process to make sure

production stays within this normal range. That is, we want to make sure the process is in a state

of control. The most commonly used tool for monitoring the production process is a control

chart. Different types of control charts are used to monitor different aspects of the production

process.

A control chart (also called process chart or quality control chart) is a graph that shows whether a

sample of data falls within the common or normal range of variation. A control chart has upper

and lower control limits that separate common from assignable causes of variation. The common

range of variation is defined by the use of control chart limits. We say that a process is out of

control when a plot of data reveals that one or more samples fall outside the control limits

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on a number of different values. Other examples are the weight of a bag of sugar, the

temperature of a baking oven, or the diameter of plastic tubing

A control chart for attributes, on the other hand, is used to monitor characteristics that have

discrete values and can be counted. Often they can be evaluated with a simple yes or no decision.

Examples include color, taste, or smell. The monitoring of attributes usually takes less time than

that of variables because a variable needs to be measured (e.g., the bottle of soft drink contains

15.9 ounces of liquid). An attribute requires only a single decision, such as yes or no, good or

bad, acceptable or unacceptable (e.g., the apple is good or rotten, the meat is good or stale, the

shoes have a defect or do not have a defect, the lightbulb works or it does not work) or counting

the number of defects (e.g., the number of broken cookies in the box, the number of dents in the

car, the number of barnacles on the bottom of a boat).

Statistical process control is used to monitor many different types of variables and

attributes.

Control Charts for Variables

1. Mean Charts : A mean chart is also known as the x-bar Chart . It is used to monitor

changes in mean of a process

The chart is constructed using the following parameters

Center line = the mean

UCL = + zx LCL = - zx Where is the average of the sample means

Z = standard normal variable ( 2 for 95.44% confidence and 3 for 99.74 confidence

x = Standard deviation of the distribution of sample means.

2. Range Chart or chart. Range (R) charts are another type of control chart for variables. Whereas x-bar charts measure

shift in the central tendency of the process, range charts monitor the dispersion or variability of

the process. The method for developing and using R-charts is the same as that for x-bar charts.

The center line of the control chartis the average range, and the upper and lower control limits

are computed as follows:

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CL =

UCL = D4

LCL = D3 Where the values for D3 and D4 are obtained from tables.

Control Charts for Attributes

Control charts for attributes are used to measure quality characteristics that are counted rather

than measured. Attributes are discrete in nature and entail simple yes-or-no decisions. For

example, this could be the number of nonfunctioning lightbulbs, the proportion of broken eggs in

a carton, the number of rotten apples, the number of scratches on a tile, or the number of

complaints issued. Two of the most common types of control charts for attributes are p-charts

and c-charts.

P-charts are used to measure the proportion of items in a sample that are defective. Examples are

the proportion of broken cookies in a batch and the proportion of cars produced with a

misaligned fender. P-charts are appropriate when both the number of defectives measured and

the size of the total sample can be counted. A proportion can then be computed and used as the

statistic of measurement. C-charts count the actual number of defects. For example, we can count

the number of complaints from customers in a month, the number of bacteria on a petri dish,

or the number of barnacles on the bottom of a boat. However, we cannot compute the proportion

of complaints from customers, the proportion of bacteria on a petri dish, or the proportion of

barnacles on the bottom of a boat. The center line is computed as the average proportion

defective in the population, . This is obtained by taking a number of samples of observations at

random and computing the average value of pacross all samples. To construct the upper and

lower control limits for a p-chart, we use the following formulas:

CL = Average proportion defective in the population

UCL = + zp

LCL = - zp Where z is the standard normal variable is the sample proportion defective p is the standard deviation of the average proportion defective

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For constructing C-chart we use the following formula

CL = Is the average number of defects

UCL = + z

LCL = - z Where Z is the standard normal variable.

ACCEPTANCE SAMPLING

Acceptance sampling is the third branch of Statistical Quality control, which refers to the process

of randomly inspecting a certain number of items from a lot or a batch in order to decide whether

to accept or reject the entire batch. The difference between Acceptance sampling and Statistical

process control is that Acceptance sampling is done either before or after a process rather than

during a process.

Acceptance sampling is used when inspecting every item is not physically possible or would be

overly expensive, or when inspecting a large number of items would lead to errors due to worker

fatigue. This last concern is especially important when a large number of items are processed in a

short period of time. Another example of when acceptance sampling would be used is in

destructive testing, such as testing eggs for salmonella or vehicles for crash testing. Obviously, in

these cases it would not be helpful to test every item! However, 100 percent inspection does

make sense if the cost of inspecting an item is less than the cost of passing on a defective item.

the goal of acceptance sampling is to determine the criteria for acceptance or rejection based on

the size of the lot, the size of the sample, and the level of confidence we wish to attain.

Acceptance sampling can be used for both attribute and variable measures, though it is most

commonly used for attributes.

Sampling Plan

A sampling plan is a plan for acceptance sampling that precisely specifies the parameters of the

sampling process and the acceptance/rejection criteria. The variables to be specified include the

size of the lot (N), the size of the sample inspected from the lot (n), the number of defects above

which a lot is rejected (c), and the number of samples that will be taken.

There are different types of sampling plans. Some call for single sampling, in which a random

sample is drawn from every lot. Each item in the sample is examined and is labeled as either

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good or bad. Depending on the number of defects or bad items found, the entire lot is

either accepted or rejected.

Another type of acceptance sampling is called double sampling. This provides an opportunity

to sample the lot a second time if the results of the first sample are inconclusive. In double sampling we first sample a lot of goods according to preset criteria for definite acceptance or rejection. However, if the

results fall in the middle range,

In addition to single and double-sampling plans, there are multiple sampling plans.Multiple

sampling plans are similar to double sampling plans except that criteria are set for more than two

samples.

Operating characteristic Curves ( OC Curves)

Different sampling plans have different capabilities for discriminating between good and bad

lots. At one extreme is 100 percent inspection, which has perfect discriminating power.

However, as the size of the sample inspected decreases, the chance of accepting a defective lot

increases.We can show the discriminating power of a sampling plan on a graph by means of an

operating characteristic (OC) curve. OC curve shows the probability or chance of accepting a

lot given various proportions of defects in the lot.

Producers risk is the chance of rejecting a lot even though the percentage defective is less than

the Acceptable Quality Limit.( AQL). AQL is the max percentage defective that the consumers

are willing to accept.

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Consumers risk is the probability of accepting a lot even though the percentage defect is larger

than the Lot Tolerance Percentage defect( LTPD). Even if the no. of defects is higher than AQL

consumers would tolerate a few more defects until it reaches a threshold limit. This upper limit

above which the percentage defects cannot be tolerated is called LTPD.

Statistical Quality Control in Services

Statistical quality control (SQC) tools have been widely used in manufacturing organizations for

quite some time. Manufacturers such as Motorola, General Electric, Toyota, and others have

shown leadership in SQC for many years. Unfortunately, service organizations have lagged

behind manufacturing firms in their use of SQC. The primary reason is that statistical quality

control requires measurement, and it is difficult to measure the quality of a service. Remember

that services often provide an intangible product and that perceptions of quality are often highly

subjective. For example, the quality of a service is often judged by such factors as friendliness

and courtesy of the staff and promptness in resolving complaints. A way to measure the quality

of services is to devise quantifiable measurements of the important dimensions of a particular

service. For example, the number of complaints received per month, the number of telephone

rings after which a response is received, or customer waiting time can be quantified. These types

of measurements are not subjective or subject to interpretation. Rather, they can be measured and

recorded. As in manufacturing, acceptable control limits should be developed and the variable in

question should be measured periodically.

Another issue that complicates quality control in service organizations is that the service is often

consumed during the production process. The customer is often present during service delivery,

and there is little time to improve quality. The workforce that interfaces with customers is part of

the service delivery. The way to manage this issue is to provide a high level of workforce

training and to empower workers to make decisions that will satisfy customers.

COST OF QUALITY- The Costs associated with quality ( for ensuring quality and the cost of

poor quality) is called the cost of quality. There are four broad categories of cost of quality-

1. Prevention

2. Appraisal

3. Internal failure

4. External failure

Module V


1. Prevention Cost The cost incurred to prevent a quality failure is prevention cost. It includes cost of training, planning, designing, equipping a quality control program, cost of

measurements, vendor certification, equipment maintenance etc.

2. Appraisal Cost Cost of evaluating, measuring, or inspecting for quality at plant or at the field is the appraisal cost. It is cost of inspection, testing, and other tasks to ensure that the

product or process is acceptable.

3. Internal Failure cost- Costs attributable to errors and defects in production at plant. Cost for defects incurred within the system: Scrap, rework, repair.

4. External Failure cost- Costs for defects that pass through the system: Customer warranty, replacements, loss of customer or goodwill, handling complaints and product repair.

The following topics please consult your assignment write up and do an independent study

ISO 9000 CERTIFICATION

TOTAL QUALITY MANAGEMENT

TPM

Maintenance and Quality Management

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