Quality management in manufacturing: who is allowed to say a part is good

Four things that have to exist before anyone can say yes

A requirement stated so that it can be checked. A method that turns the requirement into an observation, with a nominated gauge and a defined way of holding the part. A person whose signature releases the material. A record that lets somebody reconstruct the decision after the goods have gone. Struggling plants usually have three of the four, and the missing one is almost always the method. A tolerance exists on the drawing and an inspector exists on the floor, but two inspectors measuring the same feature by different means reach different answers, and the argument that follows is about people rather than about steel.

Keeping the verdict away from the pressure to ship

Whoever judges the part should not be the person whose month depends on it leaving. That does not demand a large independent department. In a small works it can be the operator, checking to a written method, holding real authority to stop. What matters is that overriding the stop is a visible act. Where a supervisor can quietly release held stock on the last afternoon of a month, the records become fiction and every measure built on them misleads. Require the override to be written down with a name against it and the behaviour shifts inside a couple of months, without anybody being disciplined.

Being wrong in either direction has a price, and only one of them shows

Two errors are possible and they are not symmetrical. Scrapping sound material costs metal, hours and sometimes a late delivery, all of it visible on the plant report by Friday. Releasing bad material costs a return, a sort at the customer, engineering time and standing that takes years to rebuild, none of which appears anywhere until it is large. Because only the first error is measured, settings drift loose over time unless escapes are tracked deliberately. Useful practice is to put an approximate value on both errors for the specific part, then tune the check to that, instead of applying one level of rigour across the catalogue.

What a shift supervisor may settle, and what has to go upward

Escalation rules prevent more argument than any procedure. A workable division gives the line authority to stop, segregate and rework against an approved instruction, and reserves for a review group anything touching use of nonconforming stock, a departure from the drawing, or material already dispatched. Name the situations rather than only the job titles, because awkward cases arrive at night. Then write the sentence most rules forget: if the reviewer cannot be reached, the material stays on hold. Defaulting to hold rather than release is worth more than the rest of the document put together.

Records a stranger can follow without a guide

A fair test of any quality system is whether an outsider can pick a part number and walk the evidence unaided: the drawing revision it was built to, the instruction the operator worked from, the gauge used and its calibration status, the readings, the signature that released it, and any concession in force at the time. If the walk needs a long-serving employee to explain the gaps, the system lives in heads rather than records and it will fail when those people retire. ISO 9001 is the general quality management standard published by the International Organization for Standardization; whether a particular system conforms is settled by an accredited assessment, never by a description like this.

Frequently asked questions

Do industrial customers genuinely insist on a certified quality system?

Some make it a condition on the purchase order, others prefer to audit your plant themselves and accept what they find, so treat certification as a commercial question before a technical one. Ask the specific accounts you are chasing rather than assuming. Certificates are issued by certification bodies whose own competence is assessed through accreditation arrangements coordinated internationally, and only that route settles conformity. A certificate evidences that an assessment took place; it is not evidence that your parts are good.

Should the quality manager report to the plant manager?

That line creates a conflict at precisely the moment independence earns its money, which is the last week of a period with an order outstanding. Groups avoid it by reporting quality into a site or divisional function with a dotted line to the plant. Smaller businesses cannot usually afford the structure, so protection has to come from visibility instead: holds logged where nobody can edit them quietly, escapes reviewed by the owner, and every override carrying a signature rather than a conversation.

How much checking is right for a factory that has just started production?

Begin heavier than you intend to end. Until you know how the process behaves, frequent checking is how that knowledge gets bought, and the cost is real but temporary. As readings accumulate, ease off on characteristics that have held steady and keep the effort on those that wander, drift with tool wear, or carry consequences downstream. The common error is fixing one plant-wide rhythm and never revisiting it, which leaves the easy features over-checked and the difficult ones under-checked.