QUALITY CONTROL-AN OVERVIEW
Quality control, now a days has become one of the most important function of management. Customer’s demand for quality product and competition from products of related concerns compel the business to maintain their quality standards.
Quality control comprises of two terms i.e. ‘quality and ‘control. Quality involves the sum of all the characteristics of a product that make it attractive and durable to customer whereas the term control refers to process of verifying that whether the production is done as per the planning or standards set or not.
So, quality control may be defined as a process of determining that whether the products confirms to the quality standards. If not, there is a need to take corrective action to remove the deviations.
METHODS OF QUALITY CONTROL:
There are basically two methods of quality control. Both of these methods are explained as follows:
Inspection is one of the most common yet important methods of controlling quality. Under this method the actual production is compared with the standard sets to check that whether the required quality is maintained or not. It is a process in which the product, material or performances comparable to standards are accepted and the rest are rejected. The inspection can be undertaken in any of the following ways:
Under this method of inspection, goods and services as per the pre decided standards are accepted whereas the products that do not fall within the standard sets are rejected.
Under this method, the causes of low quality are studied properly and corrective actions are taken to avoid any kind of rejections in future. Hence this method is more effective as compared to remedial action.
Under centralized inspection, all goods and services are inspected centrally in the inspection department. Goods which satisfied to the standards are returned to the department concerned. This method is time saving, economical and involves unbiased inspection.
Under this, the inspectors move from one floor to another or from one production process to another to do quality check. It ensures a link between the inspector and the work hence rectification can be done promptly, without any delay.
►►STATISTICAL QUALITY CONTROL:
This method has been introduced by Walter S. Schewhart and Harold F. Dodge shortly after world war 1. The method makes use of statistical principles which aims to assess on the magnitude of “chance cause variation” along with “Assignable cause variation.” The two important tools of SQC are discussed below:
►QUALITY CONTROL CHARTS:
It is a graphical representation of variations in quality. In each graph, two lines are drawn. One line is drawn above the average line called as upper control limit (UCL) and other line is drawn below the average line known as lower control limits(LCL). A sample is taken from every lot and the measure quality is plotted on the graph. If the sample cross the assignable limits, the assignable cause is determined and corrective action is taken immediately to remove those deviations.
Under this method, a sample is taken from a whole lot of finished goods and inspection is done to determine whether it meets the required standards or not. If the sample is good, it is presumed that the whole lot is good and vice versa. It generally involves two types of risk i.e. producer’s risk under which a lot of good quality can be rejected on the basis of one bad sample and the consumer’s risk, under which a whole lot of defective products is accepted on the basis of good quality sample product. To avoid these risks one can inspect more than one sample.
IMPORTANCE OF QUALITY CONTROL:
The quality control function is beneficial to both the producers as well as consumers in the following ways:
- The system of Quality control ensures that the resources must be used in the best possible way hence, control wastage.
- The consumers also feel satisfied by getting quality products at reasonable costs.
- It also helps in reduction of cost by reducing wastage and using better methods of production.
- Working in an enterprise that provides quality products provides job satisfaction and sense of accomplishment to the employees.
- The enterprises by providing quality products, enjoys good reputation in the market.
- Producers find wider markets for their quality products.