Short answer: Buyers ask us two questions during an audit - can you prove the case holds 500 kg, and can you prove the finish survives a coastal site. Both answers come from test reports, not from a catalogue. Below is the inspection sequence we run on every order, the instruments used, and the standards the numbers are measured against.
We build display cases in Shenzhen across six workshops: glass, sheet metal, low-VOC coating, woodwork, hardware and final assembly. 20,000 m² in total, roughly 200 staff, and a QC team that signs off at five gates before a crate is closed.
Gate 1 – Incoming material
Nothing enters the production floor without a batch record. Glass arrives with a certificate stating iron content and, for laminated builds, the interlayer batch and UV cut. Stainless steel is checked with a magnet and an acid spot test on every coil: 304 is non-magnetic and holds colour, 201 is not, and the difference shows up as rust on a Dubai shopfront in eighteen months.
| Incoming item | Check | Standard / instrument | Reject criteria |
|---|---|---|---|
| Laminated glass | UV cut, thickness, interlayer batch | UV-Vis spectrophotometer at 380 nm | Cut below 99.5% for museum grade |
| Stainless sheet | Grade, thickness | Acid spot test, micrometer | 201 grade substituted for 304, thickness under -0.1 mm |
| Powder coat | Batch, cure schedule | Supplier CoA, later checked at Gate 3 | Missing cure record |
| LED strip | CRI, CCT, bin consistency | Spectrometer, 3 points per reel | CRI below 95, colour shift above 3 SDCM between reels |
| Locks and hinges | Cycle rating | Supplier report, 20-cycle spot test | Visible play in the hinge after spot test |
Gate 2 – Welding and frame geometry
Museum frames are welded, not screwed, because a bolted joint opens under load and takes the seal with it. After welding we check squareness on a granite table: diagonal difference under 1.5 mm on a 2 m frame. Then the frame goes to the load rig.
The 500 kg test. A finished case, glass fitted and doors closed, is loaded to 500 kg distributed over the deck through a steel plate, held for one hour, then inspected. Acceptance is no permanent deformation above 0.5 mm measured at mid-span, no change in door alignment, and an AER re-measurement that stays within 10% of the pre-load figure. Most failures are not in the deck - they are in the plinth levellers, which is why we specify machined steel levellers rather than stamped ones on any case rated above 200 kg.
Gate 3 – Coating and corrosion
Powder coat is applied at 60 to 80 µm and cured at 190 °C for 15 minutes. Adhesion is tested by cross-cut according to ASTM D3359, method B; we require 5B (no coating removed at the edges of the lattice). Impact resistance is a 1 kg dart dropped from 50 cm on a test panel from the same batch, with no cracking to the substrate.
Salt spray. Coupons from every coating batch go into a neutral salt spray chamber per ISO 9227 (5% NaCl, 35 °C, continuous fog) for 72 hours. Acceptance is no blistering, no red rust at the scribe beyond 2 mm creep from the cut. For projects within 5 km of the coast - which in practice means most Gulf and Southeast Asian retail work - we run the same test to 240 hours and specify a zinc-rich primer under the powder.
We also keep the workshop on low-VOC water-based systems. Solvent-based paint is faster to dry and cheaper per litre, but the residual solvent keeps outgassing for weeks, and any of it that migrates into a sealed case ends up on the object. The Oddy Test rejects it outright.
Gate 4 – Assembly, lighting and function
Assembly is where a case stops being parts. At this gate we check: door alignment against a 0.2 mm feeler gauge, gasket compression at 30 to 40% of its free height, lock and hinge operation for 200 cycles, LED wiring dressed away from the object cavity, driver mounted outside the case, and the dimming curve verified from 100% down to 1% with a flicker meter.
Each unit is photographed at eight angles with a scale card, and the photos are archived against the order number. When a client reports a scratch on delivery, that archive is what settles the question of where it happened.
Gate 5 – Packing and pre-shipment
Export packing is a system, not a box. Our standard is a plywood crate on a timber skid, glass wrapped in 5 mm closed-cell foam under 3 mm hardboard, corner protectors on every frame, and a moisture barrier bag with desiccant sized to the crate volume. For ocean freight we test the design to ISTA 3E: vibration at 0.5 g from 5 to 500 Hz on a random profile, plus a 10 cm drop on each face and edge of the packed crate.
Every crate carries a packing list, a QC sign-off sheet with gate stamps, and a photo set of the interior arrangement. Customs documentation is issued against the same list, which cuts the argument at destination when a container is cleared short.
Certificates and audits
What we hold, and what an audit team will usually ask to see:
| Document | Scope | Validity | Who usually asks |
|---|---|---|---|
| ISO 9001:2015 | Quality management, whole plant | Annual surveillance | Every institutional tender |
| ISO 14001:2015 | Environmental management, coating and waste | Annual surveillance | European retail groups |
| BSCI / amfori audit | Labour and social compliance | Two-year cycle | Luxury brands with code-of-conduct clauses |
| TÜV product test reports | Load, stability, glass security | Per design family | Architects specifying EN 356 |
| CCC for tempered glass | Domestic safety glass certification | Annual | Projects shipping a bonded warehouse via China |
| Design patents (10+) | Case profiles, hinge and lighting assemblies | Per filing | Brands checking we are the source factory, not a trader |
Two honest caveats. First, a design patent is not a product certification - it protects a shape, and buyers sometimes confuse the two. Second, our ISO certificates cover the Shenzhen plant; if a project is partly subcontracted, say so in the audit scope, because an auditor who finds unlisted subcontracting moves the whole file to the watch list.
What this means for your order
If you are qualifying suppliers, ask for four documents before you ask for a price: the last ISO 9001 surveillance report, one 72-hour salt spray report from the last twelve months, the Oddy reports for the lining and adhesive on the design you are buying, and the load test record for the frame profile. A factory that can produce all four in a day is a factory that runs the gates. Send us your drawing and we will send the four documents plus a 3D render within seven days.