Managing quality - You can do it! - Part 5
In Part 4 we looked at some of the important control procedures, in this section we cover some of the basics of purchasing and look at the control of production in the factory.
Your products can only be as good as the parts you purchase. ISO 9002 requires control of both the initial selection of suppliers and of the individual orders and deliveries from the approved suppliers. Naturally you will want to keep records of how your suppliers perform and this is also required by ISO 9002.
This procedure should cover all materials and services used for manufacturing the products you sell. As a general rule you need only assess suppliers who provide goods for use in the products and can exclude other suppliers. This means that you can exclude suppliers of paper, staples and the other sundries of the business.
Supplier Selection and Approval
Before you buy products or articles you should check that the supplier is capable of supplying the goods to your specification and at the right price and time.
A first step is to send a 'Supplier Assessment Form' to the relevant suppliers (for most window fabricators this will typically be about 20 suppliers). The full assessment is then based on:
- The completed Supplier Assessment Form.
- Previous delivery record for existing suppliers.
- Quality standards held by the supplier - you do not have to buy from ISO 9002 approved suppliers but this may be a factor in your grading.
- Product approvals held by the supplier.
- Price or discounts available.
The assessment should result in a grading of the supplier (A, B, C is general) and the production of an 'approved suppliers list' giving the grading and the items approved for supply. Performance records should be maintained to make assessment an on-going process and you should be prepared to re-grade if performance gets better (or worse). Keep your suppliers involved and inform them of both their initial grading and of any changes you make.
You should purchase from your 'approved suppliers list' wherever possible and preferably from the supplier with the higher A, B, C grading. Purchase orders need to be reviewed before release to the supplier and some type of approval system set up to record both review and approval. When preparing purchase orders you should always refer to a specification or the suppliers reference number. The approach of 'I want 20 of what I had last week is a recipe for disaster'.
ISO 9002 does not prevent you from ordering over the telephone or by fax but it naturally requires that you have a system for recording and controlling these orders in some way. Copies of all purchase orders need to be retained for checking against the delivered goods at Inwards Goods Inspection and reconciliation with invoices when they arrive.
Customers rarely supply products to window fabricators but this is a requirement of ISO 9002 and some reference needs to be included to cover this. One case could be where the customer has a base for a conservatory built and then wants the conservatory put on to it. In this situation the fabricator needs to check that the base is to the required dimensions before making the conservatory. Products such as these can be treated as normal purchased goods. The customer should provide specifications and goods inwards inspection should take place to these specifications.
Product identification is needed to ensure that the right parts are used to make the products and that the finished products are delivered to the right customer. The fabricator's decision regarding the level of product labelling during production is based on the needs of the business and only relates to products and components used for the final product.
Identification should begin at the Inwards Goods area and all delivered products should be clearly marked to indicate what they are and their status. If you have a Stores Area then this requires identification of parts for good stores practice.
In window fabrication the sawn bar lengths need to be marked (using pre-printed labels or other methods) to identify the both the job and window in the job. During fabrication the labelling must continue to the extent that you can identify and trace the parts, do not be excessive! Final products need to be labelled with any production information codes and order details necessary for delivery and installation.
Quality cannot be inspected into a product but must be built into the product by good control of the processes used in the manufacture of the product. Process control is the control of production to ensure that it is adequately controlled and that quality is not adversely affected. The production operators should be responsible for the manufacture and inspection of the product to ensure quality, do not try to rely on inspectors except for random checks. The operators are the key to success. Good process control depends on:
- Clear order details for each order.
- Clear, written Works Instructions for each operation, which are always followed.
- Checklists for marking to indicate ownership and satisfactory completion of each process.
- Maintenance and checking of production machinery.
One of the most important processes in window fabrication is the welding process and special attention needs to be paid to setting out adequate controls for this process. An initial pre-start machine condition check, followed by regular weld testing of some type is necessary. It is important to realise that weld testing in fabrication is not designed to achieve an absolute number (as is required by BS 7413) but is a process control. It should identify any changes in the process that might affect the product and allow corrective action to be taken.
You will have specific customer requirements and internal or external standards. You will need to check that you meet these. Do not be excessive! Your Quality Plan will identify the responsibility for inspection and test at the relevant stages but generally these will be:
- Inward goods will be inspected to ensure that only the correct parts are delivered by the supplier and put into the product.
- In-process inspection will take place to ensure that the products are being made correctly. The operator will carry out most inspections and checks after the operation. The production checklists will verify that these have been carried out and the product is acceptable.
- Final inspection will take place before despatch to ensure that the complete product meets the customer's requirements. The window should be marked to indicate that it has been checked and is ready for despatch.
As you would expect any inspection or test should be recorded so that you can prove the product was OK at that stage (see next month).
"Managing quality" is designed to give you direct and clear information on the requirements of ISO 9002. The series has been written specifically for window fabricators but most of the information is equally relevant to plastics processing of a general nature. The series is:
Part 1: Introduction
Part 2 - The requirements of ISO 9002
Part 3 - The procedures (Section 1)
Part 4 - The procedures (Section 2)
Part 5 - The procedures (Section 3) (This section)
Part 6 - The procedures (Section 4)
Part 7 - The procedures (Section 5)
Last edited: 11/03/10
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