Quality �Management
Operations Management
Quality Management
Quality is an important dimension of production and operations management. It is not enough to produce goods and services in the right quantity and at the right time; it is important to ensure that the goods and services produced are of the right quality.
Quality as a Corporate Strategy
Quality management, which includes ensuring proper quality for a company’s output, is important not only for its survival in the market, but also to expand its market or when it wants to enter into a new product-line and various other marketing ventures.
Quality management is an important long-term marketing and organizational strategy.
What is�Quality?
What is Quality?
What is Quality and who decides what the quality should be?:
A product is called a quality product only when it satisfies various criteria for its functioning for the consumer.
Since the target-market is decided by the company, that is to which type of consumer or customer to cater to, quality is a strategic marketing decision taken by the company itself at the outset.
What is Quality?
Phil Crosby said: “Quality is conformity to certain specifications set forth by management; and these specifications must be set according to customer needs and wants”.
The decisions regarding quality are not really in the realm of one functional manager as this involves overall strategic decisions for the running of the business of a corporation.
Statistical Methods
Statistics and quantitative methods are helpful in the implementation of quality.
There are three aspects of assuring quality:
Statistical Methods
Statistical Methods
Process | Description |
Acceptance Sampling | The task of exercising control over the incoming raw materials and the outgoing finished goods. One is concerned about accepting or rejecting the supplier’s raw materials and sending or not sending the finished goods out. |
Process Control | It is assumed that if controls are exercised at raw material, process and finished goods, quality will be appropriately maintained. |
Mass Production | Statistical methods are useful for mass-production and mass-purchase or procurement of raw materials and mass shipment of the finished goods. |
Sampling | Since in all the statistical methods we shall be dealing with small samples taken from a large population, these statistical methods are of a great help in ensuring adequate quality for the total population or mass of products by checking only a few. |
Statistical Process Control
The objective of the process is to set a proper procedure to work or shape the raw materials into finished goods and then monitor the processes operating on the raw material frequently and any deviation from the said procedures should be corrected when required.
Process control is nothing but the monitoring of the various physical variables operating on the input / materials and the correction of the variables when they deviate from the previously established norms.
Statistical Process Control
Concept | Description |
Variations. | The processes which operate on the raw materials will also have variations due to causes inherent in them or otherwise. |
Monitoring the process. | We can control the processes by:
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Specification Limits for the Output. | When the quality of a particular product is being described, one usually refers to the appropriate range of performance of this product. |
Control Limits. | In exercising process control by monitoring the product from the processes, we should not exceed these specification limits. We should exercise control over the processes before the product quality goes beyond the specification limits. |
Cost Aspects in Designing Control Limits
While designing the control limits or the danger signals one should keep in mind the cost aspect as well.
Variations in any process can be described in general in terms of two parameters:
Control Charts
In process control, we keep a check on both central tendency and dispersion by a constant monitoring device; which is graphical; the graphs which are used for such monitoring are called control charts.
We resort to a sampling procedure for process control purposes. This has also another advantage by virtue of what is known as the Central Limit Theorem in statistics. The theorem states that the means of samples tend to follow a simple statistical distribution, viz. Normal Distribution.
Control Charts
x-Chart
To keep a watch on the central tendency we have to fix limits which are called control limits for the values of x. Any time the sample exceeds the control limits, we say that the process has gone out of control, that is, there are certain assignable causes which should be looked into immediately.
Control Charts
R-Chart
The standard deviation as well as the Range will give an indication of the dispersion. The Range is the difference between the maximum value and the minimum value of the observations in a sample.
When the R values fall below the central line, it indicates that the process at that point of time is having less dispersion that the average values of the same.
Control Charts
p-Chart or Fraction Defective Charts
Not in all cases can we describe the sample in terms of their measurable characteristics. Many time, the inspection is of the go / no-go, or accept / reject type.
Control charts for such inspection procedures have been named p-charts where p stands for the fraction defective in a sample.
Control Charts
c-Chart or Number of Defects Chart
A part or product is considered defective not just based on one measurement like the go and no-go gauges would indicate, but on the basis of a number of defects present in a sample.
For process control measurement in such situations where the number of defects is the criterion for acceptance or rejection, a special kind of chart called the c-chart is used.
Diagnostic value of Control Charts
It may not always be necessary for the sample point to cross the Control Limit in order to indicate trouble brewing in the process.
Many a time the trend of the sample values provides diagnostic information regarding some real trouble in the process.
Process Capability
Mass production is controlled for quality by controlling the means operating on the raw materials entering into the process. By controlling the means of production, it is assumed that the quality of the product will be controlled.
The quality of the product will be as good as the ability of the process to produce the same and will depend upon the capability of the stable system.
Managing Quality
Since each functional department has a contribution to make towards quality, it is imperative that the entire quality management effort be properly organized to coordinate the various contributing aspects to quality.
Just as in any management process, quality management also has three main components:
Managing Quality in Services
All the three components (Planning, Implementation and Monitoring & Control) are also necessary in services; since it is not inventory, quality planning assumes great importance in management of quality services.
As a result, much emphasis may have to be laid on the training of the employees in requisite skill, knowledge, orientation and attitude in addition to empowering them.
Cost of Quality
Quality management is not only concerned with maintaining the quality characteristics of a product but also with doing the same at least cost. There are basically three categories of cost of quality:
Category | Description |
Costs of Appraisal. | These are costs of inspection; testing and such checking operations as are necessary to maintain the product or service quality. |
Costs of Prevention. | These are the costs to prevent the production of bad quality output. These include costs of activity such as quality planning which tries to ensure that proper precautions have been taken to avoid wrong sampling plans being made or bad quality of raw material entering into plant or improper methods and processes being followed in the plant. |
Costs of Failure. | These are the costs of attending to customer complaints and providing product service, are included under the category of cost of failures. |
Quality Management as a Total Organizational Activity
Quality management is a total organizational activity. One has to be quality-conscious at every step of the functioning of an organization, if the organization desires to ensure the quality of its products and / or services.