How to improve quality of inspection

Dear Guest

Your question is not very clear.

a) You are the purchasor and are buying from a trading company ?

b) You are the trading company and want to stock quality valves ?

In either cases as some one deeply involved with the quality function, and that includes the vendor assessment, evaluation and training I can offer the following comments

There is no quality of inspection. the quality was in the product, and is in the process. And the process is the valve manufacturing.

Ensure tha valves are manufactured under controlled process that ensures repetibility of the product quality. The requirements to judge the quality is of course yours, or rather the equipment demand.

In case you want to purchase from a trader, ensure that the valves are from a brand that meets your quality rquirements.

The valves can be tested (in case you do not have the past data to select the brand) rigorously for the need (quality = fitness for use) and then the brand(s) may be frozen.

There are different standards available that define the testing requirements of valves (ASME, API 6D, etc) but again you can not test these for a water tap can you ?

We as users of equipments (as a part of OEM components) always go by limited vendors/ brands that go through rigorous testing and prove outs before enlisting into our approved vendor directory.

Without knowing what your present level of "quality of inspection" it's hard to suggest improvements.

If you want to improve the quality of the product, inspection will only point out the deficiencies, it will not yield a superior product. This requires a rigidly controlled manufacturing process.

Take what sb said to heart, he's right on.