Quality problems found at the customer cost the most: freight both ways, the replacement, and the next order. The same problem found at the gate costs a phone call to a supplier. Good factories check at three points.
Section 1Incoming material
Check material against the purchase order and the specification before it goes into stock. For a casting, that may be dimensions and hardness; for yarn, count and strength; for chemicals, the supplier's test certificate checked against a sample. Material that fails is held in a separate area and recorded as rejected, so it is not paid for or issued by mistake.
Section 2In-process
Set checks at the stages where a mistake is cheapest to catch: the first piece after every setup, then a sample at fixed intervals. Record readings, not just pass or fail, so you can see a process drifting before it produces rejects.
Section 3Final inspection
Before dispatch, inspect a sample from each lot against the customer's specification. Record the lot number, sample size, results and inspector, and keep the record for as long as your warranty runs. When a complaint comes, the lot number takes you straight to the material, the machine and the shift.
Handling rejections
Every rejection gets one of three decisions: rework, use as is with approval, or scrap. Record the cause. The Pareto rule works here too: a few causes usually make most of the rejections, and fixing them is the work that matters.
BIS and quality control orders
Many products in India, including several kinds of steel, cables, toys, footwear and electrical goods, are covered by Quality Control Orders. Covered products cannot be made, sold or imported without BIS certification. Check the current list on the BIS website before you launch a product or change a supplier.
In MatruOS, the quality checks of your industry are set up as registers, rejections are recorded with causes, and the lot number links each dispatch to its tests.