The review of the valve manufacturer’s approved sub-supplier list is a very important part of the consumer’s evaluation process. Most times, issues come up in plant operation because of inadequate or poor sub-supplier control of materials and manufacturing operations. It is very important to inspect all valve internals before assembly to avert problems. There are also incidents of machining issues with poor surfaces. After a while, it was seen that the valve kp-lok.com manufacturer sub-contracted 90% of their machining to different machine shops, and they were not adequately audited no QA/QC controlled. So it is very important to inspect all valve internals before assembly to avert problems.
The valve manufacturer must have a well-defined process with the right people and review period for:
- Removing poor performing sub-suppliers
- Maintaining existing suppliers
- Approving new sub-suppliers
Most times manufacturers get complacent during the process, whereby:
- Not all suppliers are on the sub-supplier approved list
- New suppliers are made use of because of urgent delivering reasons or cost
- New staffs are not trained properly to follow the right procedures
- No or not all contractor services are on the list
- By-passing the process because of over-familiarity with the supplier
- The valve manufacturer takes all decisions on his own.
Who exactly should be involved in the sub-supplier approvals?
The sub-supplier approvals should be led by procurement, quality, and engineering. These three disciplines should work together to create the sub-supplier approved list. Although other disciplines might be involved, that is when it is necessary.
A sub-supplier contact must have quality performance criteria and other key performance indicators like delivery and commercial.
How sub-suppliers are ranked
Sub-suppliers are ranked according to importance and criticality to the value. It is ranked as level 1, 2 and 3 or A, B and C. Sub-suppliers are also ranked according to internal and external assessment such as engineering audits and QA and ongoing performance monitoring.
Customers expect all these assessments to be undertaken on an annual basis and recorded with a full audit trial. The balance between “actual audit assessments” and “desktop assessments” needs to be right. Also, an internal team meeting is also very important for efficient and effective management of this list, and there must be evidence that the internal team meetings have taken place.
ISO vs. Non-ISO sub-suppliers
A very interesting discussion that is often held is the use of ISO sub-supplier versus experienced non-ISO sub-suppliers. Both the ISO and non-ISO sub-suppliers are good, but some customers are very strict and only allow ISO 9000 sub-suppliers.
Performance of sub-suppliers
The performance of sub-suppliers needs to be quantified. And how exactly is this done? Are nonconformance reports issued at the sub-supplier plant or from goods inward inspection? Does the valve manufacture visit the sub-supplier to do checking?
Customers will easily know if such checks are effective during their audit because they inspect sub-supplier check compliance and components quality. Unfortunately, most times poor quality is not identified immediately until during the manufacturing process. This is very expensive, and it also runs the risk of slowing down production. Most times, parts and components pass the inspection which should have been rejected. And so, these causes poor-performance of sub-suppliers.
Management of the approved sub-supplier list
The list should be a controlled document by QA document procedures. The valve manufacturer has to ensure procedure compliance and only certain people should be able to amend the list. Any one that is allowed to amend the list should be from upper management. The quality performance meeting should review the performance of the list and also take necessary action to maintain or improve the list.
The customers will surely access the valve manufacturer’s capability to control their sub-suppliers. Where processes are being followed by a high standard of performance is very easy and fast, and the auditor will move onto the next subject without hassle.