quality control

INTRODUCTION
Quality control is one aspect of production planning and control. It is basically concerned with quality production. Quality is a combination of characteristics pertaining to the manufacture of the product and control is the quality of the product, when the deviations in the product are more than expected. To most people quality is variable. It is subjectively judged because it deals with the relative goodness of a product. When a buyer boasts that his house or car is the best, it implies high quality.
The ultimate aims of quality system should be to enable companies to share the benefits sensibly and fairly among consumers, employees, and share holders to raise countries standard of living and to make life better for the world as a whole.
Quality control uses statistical methods, so it is referred to as statistical quality control (SQC). The effective implementation of quality control requires the participation and cooperation of all the employees at every stage of the company’s activities. They are such as market research, product planning, designing, purchasing and subcontracting production.
“QUALITY” requires developing, designing, producing, marketing and servicing products and/or service with optimum cost effectiveness and usefulness, which customer will purchase with satisfaction. To achieve these goals all the parts of a company top management must work together.
Introducing total quality enables the realization of benefits for everyone i.e. Management, consumers, employees and shareholders.
Total quality control is applicable to all the functions:
Quality at work, service, information, process, divisional units, people, system and company has to be maintained at minimum cost.
In order to implement an effective QC program, an enterprise must first decide which specific standards the product or service must meet. Then the extent of QC actions must be determined (for example, the percentage of units to be tested from each lot). Next, real-world data must be collected (for example, the percentage of units that fail) and the results reported to management personnel. After this, corrective action must be decided upon and taken (for example, defective units must be repaired or rejected and poor service repeated at no charge until the customer is satisfied). If too many unit failures or instances of poor service occur, a plan must be devised to improve the production or service process and then that plan must be put into action. Finally, the QC process must be ongoing to ensure that remedial efforts, if required, have produced satisfactory results and to immediately detect recurrences or new instances of trouble.

MEANING OF QUALITY
Quality may be defined as the sum total of features of a product which influence its ability to satisfy a given demand
Basically the quality of product and services is not defined or determined by producing firms, it is determined by customers. “The quality of product or services is a customer perception of degree to which the products or service meet his or her expectations”
Quality is essentially about learning what you are doing well and doing it better. It also means finding out what you may need to change to make sure you meet the needs of your service users. Quality is about:
• knowing what you want to do and how you want to do it
• learning from what you do
• using what you learn to develop your organization and its services
• seeking to achieve continuous improvement
• satisfying your stakeholders - those different people and groups with an interest in your organization.
DEFINITION OF QUALITY
According to John Stewart:
“There is no one definition of quality. Quality is a sense of appreciation that something is better than something else. It changes in a life time, and it changes from generation to generaFtion and it varies by facets of human activity.”
In simple words, Quality can be defined as:
“Quality is the ongoing process of building and sustaining relationships by assessing, anticipating, and fulfilling stated and implied needs.”

MEANING OF QUALITY CONTROL
Quality Control is an effective system for integrating the quality development, quality maintenance. And quality-improvement efforts of the various groups in an organization so as to enable marketing, engineering, production and service at the most economical levels, which allow for full customer satisfaction.
In order to carry on these functions a separate department is created which is called control department or simply, department of quality. The person who heads this department carries the title of manager of quality control, manager of quality assurance, or chief inspector. The level of quality control in an organization is influenced by several factors namely, the quality level of significance (e.g.: food and pharmaceutical industries), the complexity of manufacturing, and the policy of customers. Thus, each company must establish a type of organization which best fulfill its needs. Frequently, the quality control department is composed of a quality engineering function, an inspection function, an a laboratory function
Quality control (QC) is a procedure or set of procedures intended to ensure that a manufactured product or performed service adheres to a defined set of quality criteria or meets the requirements of the client or customer. QC is similar to, but not identical with, quality assurance (QA). QA is defined as a procedure or set of procedures intended to ensure that a product or service under development (before work is complete, as opposed to afterwards) meets specified requirements. QA is sometimes expressed together with QC as a single expression, quality assurance and control (QA/QC).
The phrase Quality Control is used to cover all those activities which are directed for Defining, Controlling and Maintaining quality.
DEFINITIONS OF QUALITY CONTROL
According to Alford and Beatty:
“Quality Control is that techniques of industrial management or group of techniques of industrial management by means of which products of uniform acceptable quality are manufactured.”
In the words of Broom quality control:
”Systematic control by management of the variables in the manufacturing process that affect goodness of the end product.”
In simple words, Quality Control can be defined as:
“The operational techniques and the activities that sustain the quality of a product or service in order to satisfy given requirements. It consists of quality planning, data collection, data analysis, and implementation, and is applicable to all phases of the product life cycle: design, development, manufacturing, delivery and installation, and operation and maintenance.”

OBJECTIVES OF QUALITY CONTROL
OBJECTIVES: The ultimate aim of quality control is to provide products which are dependable, satisfactory and economical. A quality control is designed to ensure economical production of products of uniform quality which is acceptable to the customer.
“Quality control aims at preventing the defects rather than detecting the defects”

1] Establishment of quality standard:
The main objectives of quality control are the economical production of a high quality of uniform product at the quality level the customer wants. Quality control is basically for eliminating variations in production and in order to have uniformity in production. So, the firm establishes quality standard to achieve its objective.


2] Locating quality deviations:
It is necessary to analyze the trend and extent of quality deviations in a manufacturing process. Such deviations should be explained by statistical techniques when they cannot be attributed to the element of chance. Accordingly the deviation must be overcome with the help of the quality standard fixed by the firm at the earlier stage.

3] Evaluation of methods and processes of production:
By evaluating the methods of processes of production, quality control helps to take corrective measures to maintain the quality of the product during the manufacture. And these corrective measures are indeed very important for the firm so as they can maintain the quality and let it not fall below the standard fixed.

4] Quick sales of quality goods:
In today’s world, consumers are looking for quality goods and services, so to live up to the consumer’s expectation the firm needs to maintain quality. Quality control accelerates the sale of the goods by supplying only the quality goods in the market. Consumers also support quality goods.

5] Production of standard quality goods:
Quality control aims at manufacturing standard quality goods. Such standard quality goods give satisfaction to consumers and also create goodwill in the market. As explained in the earlier point, that the quality goods makes quick sales, so while taking this in mind the firm go for production of standard quality goods.

6] Improvement in quality:
One objectives of quality control is to find out high quality standards and to make constant effort to reach those standards. It aims at creating quality consciousness at all levels in the organizations. Because consumers want quality goods and services, and so the firm must live up to the expectation.

EVOLUTION OF QUALITY CONTROL
OPERATOR QUALITY CONTROL
It was applicable during the end of nineteenth century. One worker or a group of workers were responsible for the manufacture of the entire product and therefore each worker controlled the quality. Since the worker or groups of workers were responsible for that particular product, more efficiency was produced. But slowly it became unpopular and as time progressed another method of quality control came into existence.

FOREMAN QUALITY CONTROL
During industrial revolution, foreman or supervisor assumed the responsibility of quality control. A production strategy designed to ensure product quality that involves a foreman responsible for directing a group of employees performing one set of similar tasks. So it can be said that maintaining quality of a product lied in the hands of the foreman or supervisor of the firm. The Foreman is responsible for supervising the inspectors at the site, and reports directly to the highest level of supervision assigned to the site, and receives daily workload from the Maintenance Manager.


INSPECTION QUALITY CONTROL
Manufacturing system became complex during world war I. this time, full-time inspectors appeared on the scene to inspect already manufactured products. Quality Control Inspection is performed to verify quality of materials, parts and final products. The object of this service is to independently assure that the activities of a specified project are being performed in accordance with all contractual specifications, codes and standards or government regulations. This is verified through checks audits, inspections and witnessing. This service is carried out completely independently of both the individual manufacturer or sub-contractor as well as the purchaser or final user. Quality Control is concerned with actual measurement or testing or supervision of manufacturers own final product control, either by inspection of each unit or by sample testing.

STATISTICAL QUALITY CONTROL
It is extension of inspection quality control. Statistical Quality Control provides the statistical techniques necessary to assure and improve the quality of products. Most of the Statistical Quality Control techniques used now have been developed during the last century. One of the most commonly used statistical tools; Control Charts was introduced by Dr. Walter Shewart in 1924. The end of World War II saw increased interest in quality; primarily among the industries in Japan. Inspectors were aided by special quality control tools like control charts. So it can be said that in this evolution of quality control, the responsibility of the inspector increases and also the quality of the product also increases at the same rate.



TOTAL QUALITY CONTROL
When step 4 was found to add inspection cost, firms began to develop a specific-decision-making and operating framework for the product quality which was effective enough to take suitable action on the quality control findings, to obtain better quality and lower costs. System for optimizing production based on ideas developed by Japanese industries from the 1950s on. The system, which blends Western and Eastern ideas, began with the concept of quality circles, in which groups of 10-20 workers were given responsibility for the quality of the products they produced. It gradually evolved into various techniques involving both workers and managers to maximize productivity and quality, including close monitoring of staff and excellent customer service. The concept of Kaizen, the notion that improvement must involve all members of a company, is central to TQC (Total Quality Control).

TOTAL QUALITY CONTROL-COMPANY-WIDE
This is Quality Management with a Quality Assurance plan. This is also the Systems Approach to Quality. Quality Management is a recent phenomenon. Customers recognize that quality is an important attribute in products and services. Suppliers recognize that quality can be an important differentiator between their own offerings and those of competitors (quality differentiation is also called the quality gap). In the past two decades this quality gap has been greatly reduced between competitive products and services. This is partly due to the contracting (also called outsourcing) of manufacture to countries like India and China, as well internationalization of trade and competition.
There are 14 formulated points of attention for managers, which are a high level abstraction of many of his deep insights. They should be interpreted by learning and understanding the deeper insights and include:

• Break down barriers between departments
• Management should learn their responsibilities, and take on leadership
• Improve constantly
• Institute a programme of education and self-improvement

ADVANTAGES OF QUALITY CONTROL
The importance of quality control is, now, accepted at a global level. It is an essential pre-condition for promoting exports. Quality control is important as it gives benefits to producers, consumers and the society at large. Consumers are now extremely quality conscious and they support quality products. They even insist for superior quality goods for their safety and protection. This suggests the importance of quality control. Even the survival of a manufacturing unit depends on its ability to supply high quality goods to consumers. It gets capacity to compete with rival producers through effective quality control. The advantages of quality control to consumers and manufacturers are:

1] LOWER COSTS:
Improvement in the designs of products and process to enable production at lower costs. Since the cost is low, it is both beneficial to manufacturer and consumer. First, when the manufacturer will produce goods and incur low cost, then he will sell to consumers also at comparatively low cost. So, at the end of the day, both the parties enjoy the benefit.

2] UNIFORMITY:
Improvement in the quality level and uniformity of the finished goods and incoming materials. If there is uniformity in the finished goods, it would be advantageous to both manufacturers and consumers. And from the point of view from the firm, it’s obligatory to maintain standard or homogeneity in their product, so as to show consistency.

3] RELATIONSHIP:
When there is uniformity in the finished goods and also high quality level, then the bond between the manufacturer and consumers has to be strengthened. In this scenario, both the parties enjoy the benefits they receive, and so the relationship improves between firm and their loyal customers.

4] ENHANCING TECHNOLOGY:
Improvement in technical knowledge and engineering data and manufacturing design. When all the above points go in right path, then we see enhancement in technology. And when the technology improves, it will again promote the firm first and later to the consumers. So, this point is again common to both in terms of advantage.

5] REDUCTION:
If the quality is improved with the enhanced technology, and if we see reduction in rejections, scrap, re-work, and inspection costs, it wouldn’t be surprising. Once the firm sets it standard and work on it efficiently, then there could be reduction in re-doing the work again and other costs.

6] EFFECTIVE COMPETITION:
Sales promotion and ability to face market competition effectively is another advantage to the manufacturer. If all the firm produces quality goods, then they can compete effectively. That competition will not only be beneficial to manufacturers alone, but the consumers will be a part of it. Because at the end of the day, their competition is for the consumers only.

7] PROMOTION:
Export promotion is possible through systematic quality control as consumers, particularly from the developed and rich countries prefer quality goods. So the firm would be getting extra profit because they can sell or they can export at a rate higher than they sell in domestic market. So, they are expanding their business and as well as they are making a good profit margin from foreigners.

STEPS IN QUALITY CONTROL/ HOW TO EXERCISE QUALITY CONTROL
Inspection is indispensable to quality control. Precisely, inspection should be of ‘least amount to furnish the control required.’ Inspection should be carefully selected and fully linked. An inspector must remain fully acquainted with his duties possessing keen insight for inspection jobs. He must be carefully instructed about his responsibilities pertaining to the end produce. The principal steps in quality control are as noted below:

1] Devising control over raw materials:
The quality of the finished product is determined mostly by the quality of raw materials. It calls for close connection between the Raw Material Purchase Department of the company and the vendors. As and when necessary, a resident inspector may be deputed by the quality control department in the vendor’s place to see that only goods in accordance with specifications are supplied. It is advisable to inspect again the raw materials before putting them to actual use.

2] Fixing standards and specifications:
In order to make any scheme of quality control successful, It is essential to predetermine standards and specifications. The practice should be to provide quality instructions in the form of drawings, showing shapes, dimensions and specifications describing color, strength, thickness, chemical composition and similar other characteristics.

3] Exercising control over production operations:
In order to execute efficient practices, the technical expert of the Quality control department must investigate, from time to time, the operating methods. When such an investigation is carried out, it helps to eliminate all possible variables.

4] Locating inspection points:
When the points at which defects occur are wrongly located or located with delay, it hinders quality control. Therefore, there should first be the inspection of the raw materials at the vendor’s places, then at the company’s plant, then at the various points during the process of production and finally at the time of packing. The defects are likely to occur at these points. The finished goods can be cleared after obtaining ‘O.K.’ or ‘All Correct’ from the quality control department.


5] Maintaining quality of equipments:
The final quality of the products is conditioned by the quality of the equipments and other devices used. Therefore, the quality control department is responsible for testing the equipment used in inspection such as gauges, which measure dimensions, electronic devices, magnetic devices, industrial radio graphical instruments and so on.

6] Maintaining records:
The quality control department is responsible for maintaining all records relating to quality inspection and control and the number rejected. On the part of the firm, this is essential because a time may arrive where they will have to take a decision on the basis on these reports of records.

QUALITY CLASSIFICATION
Quality is a relative term. It is generally stated with reference to the end us of a product. A product is said to be a good quality if it works well in a particular situation for which it is meant. Quality may be classified as per the following.

1] Quality of design:
Before the product is produced, quality of design is determined. This is the level of quality which the engineer desired the product to possess. It is desirable to get this quality level approved by marketing and operations departments. Quality of design is stated in terms of the “tolerable variations” that may be allowed for the end product e.g., two items are to be produced with similar sizes having the following specifications:

Item 1 Nominal size= 80mm, tolerance= +- 0.6mm
Item 2 Nominal size= 80mm, tolerance= +- 0.3mm
Therefore, Item 2 can be said to have better quality.

2] Quality of Conformance:
It means producing a product to meet the specifications. When a product conforms to specification, the product is considered to be a quality product e.g., two machines are to produce an item with nominal size 60mm and tolerance +- 0.1mm. Machine 1 produces a rage of +- 0.06mm and machine 2 produces a range of +- 0.03mm, thus it can be said that machine 2 has a higher quality of conformance.

3] Quality of performance:
It refers to the ability of the product to perform its function most economically. Quality of performance has three components:
[a] availability reliability and [c] maintainability.

[a] Availability:
Availability of a product is measured as the ratio of total uptime of a product and the combined time of total uptime and total downtime.

Reliability:
Reliability relates to the length of time that the product will perform its technical function satisfactorily. Reliability of a product is mostly explained in terms of meantime between failure [MRBF] which is the average time that the product functions from one failure to the next. If the MTBF is longer, the product is said to be highly reliable.

[c] Maintainability:
Maintainability relates to correction of a product to bring it to service when it has failed. Maintainability is measured by mean time to repair [MTTR].
If a product is promptly brought to correction and maintenance is carried out, then the MTTR equals to downtime of the product.
DIMENSIONS OF A PRODUCT QUALITY:
Some dimension of product quality is:
i) Performance: How will the product or service perform and meet the customer’s intended use.
For example: The speed of a sport car.
ii) Features: The special characteristics that apple to customers.
For example: The power steering of an automobile.
iii) Reliability: The likelihood of breakdowns, malfunctions, or need for repairs. Higher the reliability lesser will be the likelihood of breakdown and malfunctions, and better will be the quality of the product.
iv) Serviceability: The speed, cost and convenience of repairs and maintenance. Higher the serviceability better will the quality of the product.
v) Appearance: The human sense, the look, feel, taste, smell or sound.
vi) Customers Service: The treatment received by customer before, during and after the sale.
vii) Safety: How well the product protects users before, during and after use.

SCOPE OF QUALITY CONTROL
Quality Control believes that control must start with identification of customer quality requirements and end only when the product has been placed in the hands of the customer who remains satisfied.
Quality Control guides coordinated action of people, machines and information to achieve this goal.
Thus the Scope of Quality Control:
1) Marketing evaluates the level of quality which customers want and for which the are willing to pay.

2) Engineering reduces this marketing evaluation to exact specifications.

3) Purchasing chooses contracts with. And retains vendors for parts and materials.

4) Manufacturing selects jigs, tools and processes for production.

5) Manufacturing supervision and shop operates exert a major quality influence during parts making, subassembly, and final assembly.

6) Mechanical inspection and functional test check performance of products by comparing conformance to specifications.

7) Shipping influences the caliber of packaging and transportation.

8) Installations and product service helps ensure proper operation by installing the product according to proper instructions and maintaining through service.


NEED FOR QUALITY CONTROL
Unless quality of the product/services is properly maintained it would not be possible to obtain repeat orders through customers satisfaction. The following illustrate need for controlling quality:
(1) Quality facilitates comparison between good and bad goods n services.
(2) Controlling quality ensures marketing of goods as per specification
(3) Good quality reduces dissatisfaction of customers.
(4) Good quality cuts down the rework and rejection costs.
(5) Longer life guaranteed to the products through improved quality.
(6) Standard spare parts are used ensuring continuous flow of production.
(7) Employees report regularly on the duty because their work is not rejected.
(8) Minimum or not wastage of material and other resources.
(9) Production of quality-perfect products.
(10) Quality specifications are strictly followed.

CONCLUSION
This project presented the chronological account of the development of Quality Control and analyzed Quality Control from the perspective of scientific inquiry. The purpose of quality control is to reduce this variability to an economical minimum. It is possible to attain this objective through control of purchasing and receiving by ensuring uniformity in incoming materials and parts. Control is generally grouped under quality assurance activities.
AFTER SALES SERVICE ALSO DETERMINES QUALITY
Ensuring quality involves action on several fronts. To be specific quality control involves actions like Action supporting the product after delivery:
i) Assures that product service specification are clear and correct
ii) After that spare parts confirms to quality requirement
iii) Assure the repair and modification are performed in accordance with company quality requirements
iv) Gather and analyses complaint data from the field to measure the degrees of customer satisfaction and initiate appropriate corrective actions

The significance of quality control is, now, acknowledged at a large-scale level. It is a critical prerequisite for promoting exports. Quality control is vital as it gives benefits to producers, consumers and the society at huge. Consumers are now tremendously quality conscious and they support quality products. They even insist for superior quality goods for their safety and protection. This suggests the importance of quality control. Even the survival of a manufacturing unit depends on its ability to supply high quality goods to consumers. It gets capacity to compete with rival producers through effective quality control.
“Quality control aims at preventing the defects rather than detecting the defects”
 
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