- Cpk 1.851 (one characteristic on one part, not a blanket capability claim) on a representative length characteristic (76.1–76.5 mm), against an initial-study target of Ppk ≥ 1.67.
- 20+ inspection instruments, including two Hexagon CMMs, a KEYENCE laser microscope, and an XRF spectrometer.
- Three certificates with numbers — ISO 9001, IATF 16949, ISO 14001 — all issued by URS and verifiable.
- Full lot traceability from raw material to shipment through MES/ERP, with XRF material verification at incoming.
Read the tolerance band before you read the index. Cpk is a ratio of the tolerance band to the process spread, not an absolute measure of accuracy. The figure above was recorded on a length characteristic with a 0.4 mm band (76.1–76.5 mm) — wide by design. Hold the same process spread against a ±0.005 mm feature and it fails outright. Ask for the band, the subgroup count and the sampling window on every capability number a supplier quotes.
What quality evidence should a buyer ask to see?
The quality checklist has four items, and each maps to a document: the certificates with their numbers, the SPC evidence with its Cpk, the inspection bench with its instruments, and the traceability with its records. Ask for all four. A shop with a real quality system produces them without hesitation; a shop without one produces adjectives instead.
The sections below run through each item with the numbers this facility works to, so you can see what a complete quality answer looks like, and use it as the benchmark when you diligence any other supplier in China.
The reason quality has to be proven rather than described is that it is the one attribute invisible in a photograph. A machine, a floor, and a part all show up in a picture; a quality system does not. The only way to confirm it is through the documents it produces — certificates with numbers, charts with Cpk, instruments with calibration records, and trace chains with lot numbers. That is why every section on this page leads with the document, not the adjective.
Which certificates back the quality system?
A certificate is a document with a number, and the number is what makes it checkable. Three third-party-certified systems govern production here, each with a registrar you can contact to confirm the number is live.
| Standard | Certificate number | Scope |
|---|---|---|
| ISO 9001:2015 | 116024/A/0001/UK/En | Machining of metal parts |
| IATF 16949:2016 | 131941/A/0001/SM/En | Manufacture of CNC metal machining parts (excludes product design, Clause 8.3) |
| ISO 14001:2015 | 116024/B/0001/UK/En | Environmental management related to machining of metal parts |
Why IATF 16949 matters to a non-automotive buyer: it is the strictest quality-management standard in volume manufacturing. The SPC, FMEA, and control-plan discipline it requires for automotive parts runs on every job on this floor — you inherit automotive-grade rigor without paying a special tier.
The three certificates do different jobs, and if you know the difference, you read the quality page correctly. ISO 9001:2015 is the general quality-management baseline: it says the shop runs a documented system, controls its processes, and corrects its own non-conformances. IATF 16949:2016 is the automotive-grade layer on top of that baseline: it adds the SPC, FMEA, control-plan, and traceability discipline a moving-part supply chain demands. ISO 14001:2015 is the environmental-management standard, separate from part quality but part of the same habit of documented, audited operation. Together they mean the quality answer is not a paragraph of adjectives but a system a third party audits on a schedule.
How is process capability proven, not claimed?
Anyone can type a tolerance on a page. The proof is a control chart from an actual run, because a control chart shows the process is stable and predictable, not that one sample happened to pass. Here is the real SPC result this facility works to:
| Characteristic | Spec range | Subgroups | X̄ | Cpk | Judgement |
|---|---|---|---|---|---|
| Length | 76.1 – 76.5 mm | 25 × 4 | 76.393 | 1.851 (one characteristic on one part, not a blanket capability claim) | OK |
The internal standard is Ppk ≥ 1.67 initial on key characteristics and Cpk ≥ 1.33 on general ones. A Cpk of 1.851 (one characteristic on one part, not a blanket capability claim) sits comfortably inside spec — the chart tells you the process will keep producing good parts, which is a stronger statement than any single measurement. If a print demands a dimension the process cannot reliably hold, that is flagged during the design-for-manufacturing review, before any chip is cut.
Two capability indices look alike and answer different questions, and if you know the split, you can read a report instead of just accepting it. Cpk measures both how centered the process is and how wide its spread is, against the spec — it is the number to ask for on an established, stable process. Ppk measures the same thing over a shorter, initial sample, before the process has proven its stability over a long run. A shop that hands you a Cpk is showing sustained performance; a shop that hands you a Ppk and calls it a Cpk is showing a snapshot. The distinction matters because you are buying the process, not the snapshot.
Which inspection instruments verify dimensions?
Verification is only as good as the instruments behind it. The metrology bench here is the same class a buyer would use to audit the shop, and it covers dimensional, surface, and material checks:
- Hexagon GLOBAL S CMMs (2) — dimensional verification on 3D geometry.
- KEYENCE VK-X3000 laser microscope — surface profile and micro-feature measurement.
- SURFCOM 1800D — surface roughness and contour.
- iCHEQ XRF spectrometer — alloy composition against the mill certificate at incoming.
- Micro-Vickers hardness tester, Fischer coating-thickness gauge, salt-spray chamber, tensile tester — material and finishing verification.
- Gear measuring center and vision measuring machines — complex and micro geometry.
An instrument is only as trustworthy as its calibration, and calibration is only as trustworthy as the chain behind it. A CMM or a micrometer should be checked against a standard that traces back to a recognized reference, and the record of that check should be available. The same logic applies to the measurement system as a whole: a gauge repeatability and reproducibility study, or GR&R, shows how much of the measured variation comes from the instruments and operators rather than the part itself. A shop that runs GR&R on its critical measurements is telling you its numbers are the part's numbers, not the gauge's noise. Ask to see the calibration record for the instrument named on your report — it is one more document a broker cannot reach for.
How are parts traced from raw material to shipment?
For regulated buyers, traceability is the difference between an isolated lot and a recall. The MES/ERP system records the full chain on every job: raw material source and usage, process parameters, machine data, production batch, machining time, operator, and inspection results. Incoming material is XRF-checked against the mill certificate before it reaches a machine, so a mixed lot is caught at the door.
If a non-conformance ever surfaces, the record can name the exact lot, machine, and operator, and isolate the impact instead of guessing. That is the same discipline an IATF 16949 audit looks for, and it runs on every job, not just automotive ones.
The business value of that record is containment, not nostalgia. When a defect is found in the field, the difference between a recall and a targeted correction is whether the shop can say exactly which lot, which machine, and which operator produced the suspect parts. A full trace chain narrows the impact to the parts that actually share the problem; a shop without one has to treat every part it ever shipped as suspect. For a regulated buyer, that is the difference between a contained non-conformance and an open-ended liability, and it is why traceability is a quality-system requirement rather than a paperwork nicety.
How are defects prevented before machining starts?
Catching a bad part after machining is expensive; preventing it during planning is cheap. The APQP/PPAP sequence does exactly that, and it is produced before the first setup:
- Process flow chart — maps every step from incoming to shipment so no operation is skipped.
- PFMEA — failure modes with severity, occurrence, and detection ratings, plus countermeasures defined before cutting.
- Control plan — the critical characteristics, measurement method, and sampling frequency for each step.
- SPC — control charts on key characteristics to catch drift before it produces a defect.
This is the sequence automotive OEMs audit for, and running it on every job is how a defect is kept from ever leaving the floor.
The APQP/PPAP sequence has levels of depth, and you should know which one their part needs rather than paying for all of them by default. The lighter levels confirm the process and a dimensional layout; the heavier levels add the full statistical package — capability studies, control charts, and material certification — to the submission. A supplier that asks which level your program requires is tailoring the documentation to the risk; a supplier that quotes a single flat "PPAP" without asking is charging you for the heaviest package whether or not your part warrants it. The question to put back to the supplier is simple: "which level does my part need, and what does that include?"
What quality documents ship with the parts?
You should not have to ask for proof after the parts arrive. Depending on the program, the shipment includes a first-article inspection report (full dimensional layout against the drawing), a CMM inspection report (measured values for critical dimensions), SPC control charts (evidence of stability), and the material certificate (alloy and heat, XRF-verified at incoming). The point is documented evidence of what you received — the same evidence you use to diligence the shop in the first place.
The documents differ in what they prove, and you should not confuse them. A first-article inspection, or FAI, is a complete dimensional layout of one part against every call-out on the drawing — it proves the process can make the part once. A CMM report on critical dimensions proves the features that matter are measured, but it may not cover the whole print. SPC charts prove the process is stable across a run, and the material certificate proves the alloy is what was ordered. Together they answer four different questions, and a shop that sends all four is giving you the full picture rather than the flattering slice.
What this shop actually runs
If you ask for capability evidence, you deserve a specific answer. This facility operates 100+ CNC machines across 6,800 m2 in Dongguan, China, staffed by 100+ people. The machines, listed by category:
- 5-axis machining centres (10+) - Mazak VARIAXIS I-600 (510/910/510 mm travel, 12,000 rpm, 22 kW, 71.6 N·m, 30-tool BT40) and Mazak INTEGREX I-250H S (B-axis 0.0001°, 24 kW, 124 N·m, 38-tool HSK-A63). Geared to compound-angle parts, single-setup multi-face prismatic work, and aerospace fittings where datum transfer loss is unacceptable.
- 3-axis / 4-axis machining centres (50+) - Brother SPEEDIO S500Z2N / S700Z2N (10,000 rpm, 14/21-tool ATC, 0.7 s tool-to-tool, Z-axis 2.2 G) and Mazak VCE-430A L / VCE-570C L (10,000 rpm, 118 N·m, 24-tool ATC). Geared to prismatic parts, plates, brackets, housings.
- Swiss-type turning centres (10+) - Citizen Cincom A20-3F7 (Φ20 mm, 10,000 rpm), TSUGAMI B0206-III / B0205-III (Φ20 mm, 0.1 µm), STAR SR-32JII / SR-32J Type N (Φ32 mm, 8,000 rpm). Geared to long, slender rotational parts at ±0.002 mm.
- CNC turning centres (20+) - HEADMAN T70M/1250 (720 mm swing, 117 mm bore, 3,000 rpm, BMT75 12-station turret). Geared to shafts, bushings, flanges up to ±0.002 mm.
- Wire EDM (5+) - Sodick AQ535L (550/350/300 mm travel, ±20° taper, 800 kg workpiece). Geared to hardened tool steel, internal splines, sharp internal corners that milling cannot reach.
- Inspection: Hexagon CMM + 20+ gauges - Hexagon CMM for coordinate measurement, plus vision system, profilometer, hardness tester, coating thickness gauge, XRF for material verification. The 10:1 rule (gauge 10x more accurate than the band) is applied to every feature.
- Machine highlights - VARIAXIS I-600: one-setup multi-face 5-axis + MAZA-CHECK auto-calibration; INTEGREX I-250H S: DONE-IN-ONE mill-turn, B-axis 0.0001° + Ai thermal shield; SPEEDIO S500Z2N / S700Z2N: Z-axis 2.2 G + 0.7 s ATC; Swiss-type: guide-bush switchable + 0.1 µm resolution.
Tolerance bands: ±0.003 mm milled, ±0.002 mm turned, ±0.002 mm ground or wire-cut. Capability indices: Ppk >= 1.67 at the initial study; Cpk >= 1.33 ongoing in production.
Certifications: ISO 9001:2015 (116024/A/0001/UK/En) · IATF 16949:2016 (131941/A/0001/SM/En, design clause 8.3 excluded) · ISO 14001:2015 (116024/B/0001/UK/En), held by Dongguan Zhuohang Ltd (USCC 91441900MA4UWT6X39, since 2005).
Service area: we supply Austria, Belgium, the Czech Republic, Denmark, France, Germany, Greece, Hungary, Ireland, Italy, the Netherlands, Spain, Sweden and the United Kingdom in Europe; Brazil, Canada, Mexico and the United States in the Americas; China, Israel, Japan, Singapore and Sri Lanka in Asia; Australia and New Zealand in Oceania; and South Africa in Africa, with worldwide delivery from China.
Contact: Felipe Iglesias, [email protected], +86 13126536955.
Ask to see the quality evidence before you order
Request a sample CMM report and SPC chart — email [email protected] or call +86 13126536955.
Frequently Asked Questions
What certifications back the quality system?
In short, The facility holds ISO 9001:2015 (116024/A/0001/UK/En), IATF 16949:2016 (131941/A/0001/SM/En), and ISO 14001:2015 (116024/B/0001/UK/En), all issued by URS. The IATF 16949 scope excludes product design under Clause 8.3, so the shop operates as a build-to-print manufacturer with automotive-grade process control.
How do you prove process capability rather than claim it?
In short, The shop runs SPC control charts on key characteristics. On a representative length characteristic of 76.1–76.5 mm, the chart showed Cpk = 1.851 (one characteristic on one part, not a blanket capability claim) across 25 subgroups, against an internal target of Ppk ≥ 1.67 initial for key characteristics and ≥ 1.33 for general characteristics — a stable, predictable process, not a single passing sample.
What inspection equipment verifies dimensions?
In short, Two Hexagon GLOBAL S CMMs, a KEYENCE VK-X3000 laser microscope, a SURFCOM 1800D profilometer, an iCHEQ XRF spectrometer, micro-Vickers hardness testers, and coating-thickness, salt-spray, and tensile testers. The bench is the same class of instrument a buyer would use to audit the shop.
Can parts be traced back to the raw material?
In short, Yes. The MES/ERP system records material source, process parameters, machine data, batch, operator, and inspection results for every lot, and incoming material is XRF-checked against its mill certificate.
What quality documents ship with the parts?
In short, Depending on the program, the shipment can include a first-article inspection report, a CMM dimensional report, SPC control charts, and the material certificate. You receive documented evidence of what was measured and verified, not just a pass-or-fail note.
How are defects prevented before machining starts?
In short, Through the APQP/PPAP sequence: a process flow chart, PFMEA, control plan, and SPC are produced before cutting, so failure modes and their countermeasures are defined during planning. This is the discipline IATF 16949 audits for, and it runs on every job rather than only automotive ones.
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Standards referenced on this page
- IATF 16949:2016 — Automotive quality management system standard
- ISO 14001 — Environmental management systems — Requirements with guidance for use
- ASTM A582/A582M-12 — Standard Specification for Free-Machining Stainless Steel Bars