The determination of quality can be a complex problem with a variety of people making some contribution. It is important therefore, that the process is properly coordinated. This can be done in several ways:
(a) As a member of committee concerned with specification and standardization, purchasing staff should:
i. Advise on costs, especially of alternatives.
ii. Advise on availability of materials to the specified quality
iii. Advise on suitability of requisitioned items for a particular purpose.
(b) By ensuring that suppliers meet quality requirements through:
i Seeing that appropriate references to quality are made in enquiries, purchase orders and conditions of purchase,
ii Vendor appraisal with regards to quality,
iii Implementing a programme of quality assurance,
iv Vendor rating, with reference to quality,
v Soliciting for vendor assistance in connection with quality,
vi Relation with suppliers in respect of rejected or unsatisfactory goods,
vii Ascertaining that the supplier has a satisfactory quality control system
Control of Quality
Effective control over quality standards demands two essential requirements:
(a) The ability to describe the need in a way that the supplier can clearly understand what is required;
(b) The creation of systems of examining or testing that the quality requirements is being adequately met.
The first requirement must be considered carefully when the quality is being determined and subsequently when the order on the supplier is being prepared.
Methods of Describing Needs
To satisfy the first requirement for effective control over quality, it is vital that one describes one’s needs accurately and in a manner that the supplier is unlikely to misunderstand. There are many ways of describing needs, each being appropriate in specific cases. They include the following:
By market grade
This method is most appropriate in indicating the quality of natural commodities such as timber, cotton, tobacco, cocoa, fruit, etc. Standards of size, shape, degree of perfections and other characteristics of quality are agreed by the producers and buyers, and grades applied can be quoted by the buyer to indicate the level of quality he requires.
By brand or trade name
Where one is buying manufactured goods which are in common use, the producers frequently give such goods brands or trade names. This distinguished their product from those of competitors and, in due course, a brand becomes known for the standard of quality, services, value, etc: that it provides. Buyers should of necessity, avoid the dangers of being too dependent upon a particular brand.
By commercial standards
Many individual goods are manufactured to a standard specification by all products. This means that by ordering to a simple standard description,the buyer can be sure of the level of quality, workmanship and performance he will receive. Bolts and nuts, pipe fittings, electrical products and many others fall into this category.
By specification
In many circumstances, a buyer’s need cannot be specified by standard specifications or brands, as they are required to perform a specific purpose or to fit into a particular design or method of manufacture . In such cases, the company must prepare its own specifications. This is the area in which it becomes very difficult to ensure that the supplier understands exactly what is required. To ensure that a specification will result in exactly the right item being obtained, great care must be taken in describing where appropriate:
(i) Physical characteristics
(ii) Chemical properties
(iii) Dimensions and tolerances
(iv) Appearances and finish
(v) Testing requirements to be met
(vi) Condition of material content (heat treatment, etc)
These and many other qualities may need to be fully described in a written specifications. It then requires detailed inspection to determine that the specification has been met.
By performance specification
This method of describing what an item is required to do, rather than what it is, can be used when one is buying goods with which the producer is more conversant with than the buyer. A material may be required to withstand a particular temperature or carry a certain electrical load; an oil may be required to lubricate certain speeds or resists acid. It is often easier to tell the producer the performance required than to specify the materials themselves.
By material and method of manufacturing
When the buying firm is more technically advanced than the supplier, it may be considered advantageous to specify exactly how a requirement should be produced and the specification of the materials it should be made from. It must be realized, however, that the buyer must then take complete responsibility for the end results.
By drawings or blue print
These are often used to supplement a specification where many precise dimensions or shapes are involved. Whilst they may be expensive to produce, they are precise; they illustrate clearly what product should look like and they provide clear standards for inspections purposes.
By samples
It is sometimes considered that this is the easiest way to ensure that you get exactly what you want, but it is usually very difficult to determine whether the finished article is precisely the same as the sample in terms of material specification, workmanship, etc. However, when a requirement is very difficult to describe, a sample may be the best way to specify one’s needs.
Methods of controlling Quality
Control over quality is not simply a matter of inspecting incoming goods and rejecting those which do not meet, the required standard. Inspection alone cannot put quality into a product, it can only prevent poor quality items proceeding any further, but considerable waste must have already occurred which must reflect on the ultimate costs.
The nearest we get to total quality control is through the following four stages:
- Preparation of clear and accurate description in the first place;
- Analysis of potential supplier’s true capabilities to meet required quality standards;
- Selection of those suppliers who have the best chance of meeting quality requirements
- Continuous evaluation of suppliers performance in meeting quality standards
Preparation of clear and accurate descriptions:
We had earlier examined the methods used to describe requirements.
To ensure that the said methods provide sound basis for control of quality, the purchasing staff will perform the following duties:
(a) Have a clear understanding of quality requirement.
(b) Ensure that the quality requirements are reasonable and realistic in relation to cost.
(C) Be satisfied that the quality requirements stated, give reasonable opportunities for obtaining competitive prices.
(d) Ensure that potential suppliers can be properly assessed on meeting quality standards.
Analysis of potential supplier’s capabilities.
Whilst suppliers are selected on the basis of other factors other than quality, the latter is likely to create additional cost than say any other, if it is not right in the first place. The following methods may be used to assess capability:
(a) Product testing: Whilst this is not feasible in all there are circumstances in which it can be used to good effect.
(b) Analysis of potential suppliers’ quotation possible from a careful scrutiny of quotations to determine the capability or attitude of potential suppliers to quality
standards.
(c) In-plant capability survey- in large-scale purchases, it is frequently worthwhile to inspect the facilities of the potential supplier to examine
– the production equipment available
– the methods of quality control employed
– the skills available in the company
– the attitudes of managers and production staff to quality
– the handling and storage of materials
Selection of suppliers
The ultimate choice of supplier, as far as quality is concerned, will be far easier where some care has been taken, in the
earlier steps described above. However, additional consideration to be taken into account in the final selection are
as follows:
(a) Is there adequate motivation for the supplier to maintain a good performance in maintaining quality standards?
(b) Is there likely to be good understanding between the supplier and the buyer on quality materials?
(c) Shall we be able to maintain good working relationships with the supplying company on a continuous basis?
Continuous evaluation of supplier performance.
The earlier performance can be evaluated, the less damage will be caused by poor goods being supplied, but evaluation shall not be restricted to the inspection of incoming goods. Some ways of evaluating performance on a continuing basis are:
– the buying company having their own inspection working in the supplier’s plant or factory permanently;
– a regular review meeting being held, at which the buyer and personel from the supplier examine all aspects of maintaining quality.
– individual suppliers being held responsible personally for the quality supplied;
– records being maintained of costs, losses and problems cause by the defective supply for which the supplier has agreed to be responsible.