Risk-Based Quality Coordination
Outgoing inspection and packaging verified before shipment against your acceptance criteria, with a sealed master sample kept for batch comparison.
Magnet quality problems are usually discovered too late to be cheap. A container is loaded, paid for, and only then opened and inspected — and by that point an out-of-tolerance arc, a weakly oriented lot or a demagnetized batch is the customer's problem in both senses: it stalls a line, and it is difficult to remedy from another continent. This capability moves the verification in front of shipment, against a reference the customer has already approved.
The Customer Problem
Inspection may use sampling, automated checks or full inspection depending on the agreed plan, so a batch is approved in aggregate, and the real risk sits in the difference between that batch and the last accepted one. Payment terms on a full container concentrate that risk into a single moment: once the money has cleared, the customer's leverage is limited to a claim and a conversation.
- A batch arrives out of tolerance and the assembly cannot be built, with no verified reference to compare it against.
- Magnets pass an incoming dimension check but are measurably weaker once inside the assembly.
- Packaging that failed in transit has damaged brittle parts, or exposed plated surfaces to corrosion before use.
- There is no record of what was checked, or on which batch, so a dispute becomes a matter of opinion.
- Repeatability cannot be demonstrated between batches, so the customer cannot tell when to accept and when to reject.
What We Do
We coordinate quality around the risks that actually apply to the part, before the goods leave:
- Retain a sealed master sample agreed with the customer, and use it as the physical reference a batch is compared against.
- Coordinate the producing factory's outgoing inspection against the standards agreed for that part — dimensions, magnetic parameters and surface condition, per the inspection items fixed on the production drawing — and review the results per project risk.
- Verify packaging and protection, which matters most for brittle ferrite and for NdFeB supplied with a plated surface that has to survive transit.
- Keep batch records, inspection results and packaging verification together, so the evidence exists if a question is raised later.
- Handle a claim as a single point of contact: ProfurtherMag receives the complaint, verifies the evidence and coordinates the factory and the remedy, with the outcome and the responsibility settled on the facts and the terms agreed in the order.
What a Risk-Based Inspection Actually Fixes
An even split of inspection effort across a drawing is easy to defend and wrong. Effort should follow what a failure costs at assembly, not how convenient the feature is to measure. A mark on an uncoated arc is cosmetic; a wall that runs to the wrong side of its band stops the part entering the rotor. Both can be measured in the same second on the same bench, and only one of them earns a check on every piece.
A delivered pump-motor stator arc, supplied since 2017, shows the allocation. It is supplied uncoated and unmagnetized, with radial magnetization, two arcs per steel yoke, at 30–35 days per batch: Br 380–400 mT, Hcb 230–275 kA/m, (BH)max 27–32.5 kJ/m³. Its two unilateral limits, inner radius R27 +0.2/0 mm and wall 8.5 −0.1/0 mm, are both biased the same way, so dimension error can only make the magnet smaller — it can never intrude into the rotor space. That bias is what lets the drawing carry a hard limit instead of a symmetric one, and it is also what tells us which checks to weight.
| Outer radius, R35.5 ± 0.1 mm | Factory outgoing inspection, on the seated face. Full check: this feature positions the arc in the yoke, so drift here appears as an assembly fault rather than a magnet fault. |
|---|---|
| Inner radius, R27 +0.2/0 mm | Same stage, same section. Read against the zero side of the band: the bore may open, never close, which is what keeps the arc clear of the rotor space. |
| Wall, 8.5 −0.1/0 mm | Same stage, measured with the inner radius as one section, since the pair together define the rotor clearance. |
| Section, 63 ± 0.1 × 40 ± 0.5 mm | Same stage. The two bands differ because they do different work; neither is interchangeable with the other. |
| Br 380–400 mT, Hcb 230–275 kA/m, (BH)max 27–32.5 kJ/m³ | Sampled per lot on magnetized samples before shipment — these cannot be read from the part as delivered unmagnetized. |
| Surface condition, supplied uncoated | Visual, sampled. A mark here does not stop assembly, so it does not take the effort the interface geometry takes. |
A 2018 fan and blower project makes the other half of the argument. The batch was rejected at the customer's assembly because the end chamfer was too tight for the plastic holder's seating point, although no dimension on the supplied drawing was out of tolerance. Drawing conformance is not assembly conformance. The chamfer had never been stated as an interface feature with a band of its own, so inspection could pass it correctly and the assembly could still fail — and an even check of the drawing would never have caught it.
So the effort is placed where the failure lands: interface geometry checked full at outgoing inspection, magnetic parameters sampled per lot, surface and packaging looked at in proportion. Factory outgoing inspection stays the base for a shipment; the risk-based review sits on top of it, on site or by a third party, at a level set by the project's risk rather than a visit on every batch.
Expected Outcome
The outcome is batch-to-batch repeatability, compared against the reference sample, with the arrangement recorded in the order. Each incoming batch can be compared against a sealed reference and a written inspection record instead of being judged from appearance, which keeps the acceptance decision factual. Where the customer's risk profile calls for an additional independent check, third-party laboratory inspection can be arranged as part of the outgoing routine.
What This Capability Changes for a Project
The problem a project arrives with, what we do about it, and the result the work is measured against.
When This Capability Fits, and Where It Stops
The projects this work suits, the input it needs from you, and the limits it states before a project starts.
Technical articles that reference this capability.
- Custom Magnets from China: What to Confirm Buying / Sourcing Guide
What to confirm before a custo…
- Magnet Tolerances, Grinding and Plating Technical Guide
How critical tolerances are re…
Bring Us the Starting Point You Have
A sample, a partial drawing or an operating condition is enough to begin. Tell us what the magnet has to do and we will tell you what the evaluation can and cannot settle.