Manufacturing Process

Twelve Steps, And What Can Go Wrong At Each One

A supplier list says what a factory can make. This page says how, in what order, and which measurement stops a bad unit from travelling — the set of answers a buyer's engineer asks for.

Every step below happens under one roof, which is the practical difference between a factory and a trading desk: when a coating fails an adhesion coupon, the polishing line that caused it is a hundred metres away and is adjusted the same week. The four lines under each step are the same four questions — the machine, what is held to a number, how the process fails, and how that failure is caught.

Tube cutting and blanking

Equipment: Automatic tube cutters and blanking presses, fed from 304 coil.
Held to a number: Cut length to drawing tolerance, squareness of the cut face, and no deformation of the tube wall.
How it fails: Burrs left on the cut edge, and an angled cut face that will not sit flat in the forming die.
How it is caught: First-off sample against the drawing, then a dimensional check per batch with the burr condition recorded.

Metal forming and necking

Equipment: Rotary forming and necking stations, plus the threading head for the lid interface.
Held to a number: Neck diameter and roundness, wall thinning at the shoulder, and the thread pitch that decides whether every lid in the range fits.
How it fails: Wrinkling or splitting at the neck radius, and a thread that binds on one lid design and not another.
How it is caught: Dimensional card per batch plus a lid-fit gauge — the same gauge a sample is checked against before it is sent.

Cleaning and degreasing

Equipment: Multi-stage ultrasonic and rinse line.
Held to a number: Oil and drawing-compound residue on the surfaces that will be welded, coated or used as a drinking surface.
How it fails: Residue left in the base radius, which shows up much later as a coating that lifts or a weld that will not take.
How it is caught: Water-break test on the surface and a wipe check per shift.

Welding and seam sealing

Equipment: Automatic circumferential welding for the base and the neck joint.
Held to a number: Weld penetration and continuity around the full circumference, with no undercut at the toe of the weld.
How it fails: A pinhole or a cold lap — invisible on the outside, and the single most common cause of a body that will not hold vacuum.
How it is caught: Visual and dye-penetrant sampling, plus the vacuum test at the next stage that catches anything the sample missed.

Vacuum brazing and evacuation

Equipment: Vacuum brazing furnaces for the inner/outer wall joint, then individual evacuation and sealing.
Held to a number: The vacuum level inside the wall gap, and the integrity of the seal that holds it for the life of the product.
How it fails: A partial vacuum, which passes a quick check and then loses retention over a few weeks as the gap draws air.
How it is caught: Every body is evacuated and measured individually. Not sampled — see the note in the performance block above.

Polishing and surface preparation

Equipment: Polishing lines and the pre-treatment stages for coating and plating.
Held to a number: Surface roughness before coating, and the absence of polishing compound in the areas that will be printed.
How it fails: A polished surface that is too smooth for the coating to key to, which fails an adhesion test weeks later rather than on the line.
How it is caught: Adhesion coupon per batch, tested to ISO 2409 / ASTM D3359 before the run is released.

Coating, plating and colour

Equipment: Powder-coat and spray lines, plus vacuum metallising for plated finishes.
Held to a number: Dry film thickness, colour against the approved Pantone reference, and cure schedule.
How it fails: Under-cured coating, which feels and looks correct on the day and chips on the shelf; and a colour that drifts between the first and the last carton of a run.
How it is caught: Thickness gauge and colour check against the approved chip on every batch, with the cure log kept against the order.

Decoration and printing

Equipment: Silk-screen, heat-transfer, water-transfer, air-transfer and 3D UV print lines; laser and embossing for the engraved methods.
Held to a number: Registration and colour against the approved print proof, and the depth of a laser or embossed mark.
How it fails: Registration drift across a taper, and a screen that clogs and prints a thin or broken mark.
How it is caught: A decorated sample off the run is compared with the approved proof at the start, the middle and the end of the batch.

Assembly and lid fitting

Equipment: Assembly cells for the lid, gasket, handle, straw and accessory set.
Held to a number: Gasket seating, lid torque and the presence of every component the order calls for.
How it fails: A gasket seated with a twist, which passes a static check and leaks once the bottle is carried on its side.
How it is caught: Lid function cycles measured per order, plus a filled inversion test on every unit.

Inspection and laboratory testing

Equipment: In-house laboratory: hardness, wall thickness, adhesion, thermal retention and salt spray.
Held to a number: The performance the product was specified to reach, measured on the production article rather than on a golden sample.
How it fails: A test run on a hand-built sample that the production tooling cannot repeat — the reason the lab tests the run and not the prototype.
How it is caught: Retention, adhesion and cycle results recorded against the order before release.

Pre-shipment inspection

Equipment: Inspection bench with the approved limit sample and the customer specification.
Held to a number: Appearance against the limit sample, packing configuration, carton marking, and quantity.
How it fails: A mixed carton built from two colour batches, which only surfaces at the buyer's distribution centre.
How it is caught: AQL sampling per the agreed plan, with photographs and a written report issued before the container is loaded.

Packing, marking and loading

Equipment: Packing lines with polybag, white box, colour box, PDQ and mailer formats; barcode and carton-marking stations.
Held to a number: Carton configuration, unit count, transit protection and the marking the buyer's warehouse scans.
How it fails: A carton that passes a static check and fails ISTA transit, or a barcode placed where a retail scanner cannot read it.
How it is caught: Carton drop and vibration per ISTA where the buyer asks, and a loading plan drawn against the container before the truck arrives.

Performance

Thermal, Vacuum And Leak — Measured, Not Described

Insulation is developed to the retention your market claims rather than to a house number, and every body is vacuum-tested on its own before assembly. The figures below are the envelope our standard double-wall bodies reach; the method behind each one is stated so your own lab can reproduce it.

How It Is Tested

24hours Cold retention Up to 24 hours holding cold on a standard double-wall 500 ml+ body, measured filled and closed at 20 °C ambient. Tell us the retention your market claims and we will say which body, lid and wall gap reaches it.
12hours Hot retention Up to 12 hours holding hot to the same method. Hot performance is decided by the lid as much as the body — an open chug lid loses heat far faster than a sealed screw cap.
100% Vacuum tested, piece by piece Every body is evacuated and measured individually before assembly. This is not an AQL sample: an AQL plan would tell us how many units leak, never which ones, and a leaking vacuum body cannot be fixed after the walls are sealed.
100% Leak test on finished units Assembled and filled units are inverted and checked before packing. The test is recorded against the order, so a claim months later can be traced to the batch it came from.
8checks Documented control points Incoming material, in-process inspection, performance, appearance against the limit sample, lid function cycles, pre-shipment AQL, documentation and traceability, and after-sales response. Each has an owner and a record.
FDA · LFGB Food-contact developed Materials and coatings are selected against FDA 21 CFR and LFGB §30/§31 from the start, not screened afterwards. Test reports are issued per model and per destination market.

Standards

What The Process Is Measured Against

The standards the production route is developed and tested to. Naming them is the point: a buyer can look each one up, and the report we send references it.

Food contactThe materials and coatings that touch the drink.

Standard	Where it applies	What it covers
FDA 21 CFR 175.300 / 177.2600	United States	Resinous and rubber coatings and their extractives, tested against the food-contact conditions the product is used in.
LFGB §30 & §31	Germany	The German food-contact test most European buyers name in a specification, covering both the article and the sensorial change it causes.
EU 1935/2004 · EU 10/2011	European Union	The framework regulation and its plastics measure; declarations of compliance are written against them.
GB 4806.9	China	The national food-contact standard for metal materials and articles, used for the domestic market and for buyers who mirror it.
UK Food Contact Materials Regulations	United Kingdom	The retained GB regime, which is not the same document as the EU one and is often asked for separately.

Substances and restricted materialsWhat must not be in the article, and how it is declared.

Standard	Where it applies	What it covers
REACH (EC) 1907/2006 — SVHC	European Union	Screening against the candidate list, reported per article with the concentration found.
California Proposition 65	California, US	Declarations covering lead, cadmium and the other listed substances in the body, the coating and the decoration ink.
CPSIA	United States	Lead and phthalate limits where a product or a lid can reasonably be expected to be handled by a child.
RoHS	European Union	Relevant only to products carrying electronics — a temperature-display lid, for example — and stated separately when they do.

System and socialHow the site is run and how the people who work in it are treated.

Standard	Where it applies	What it covers
ISO 9001	Quality management system	Certified against the system under which orders are planned, produced, inspected and released.
ISO 14001	Environmental management	The environmental management system covering the production base.
BSCI / Sedex SMETA	Social compliance	Third-party audits of labour standards, working hours, wages and site safety, commissioned by the buyer community rather than by us.

Performance and durabilityWhat the article has to survive, measured.

Standard	Where it applies	What it covers
EN 12546-1	Vacuum ware	The European standard for vacuum flasks and insulated containers — capacity, thermal performance and the marking on the article.
QB/T 2332	Vacuum flask	The Chinese standard for the same product family, used as the in-house performance baseline.
ISO 9227	Salt spray	Neutral salt-spray corrosion testing on coated and plated bodies.
ISO 2409 / ASTM D3359	Coating adhesion	Cross-cut and tape tests on the finish, which is where a cheap powder coat fails first.
ISO 15184	Pencil hardness	Surface hardness of the coating against a defined pencil grade.

Transit and packagingWhat happens to the carton before the buyer opens it.

Standard	Where it applies	What it covers
ISTA 1A / 2A	Transit packaging	Drop and vibration protocols on the packed carton, which is the test that finds a carton that will not survive a container.
FSC	Paper and board	Chain-of-custody on the board used in the retail box and the display unit, where a retailer asks for it.

Test reports are issued against a specific product and a specific destination market. Tell us your item number and where the goods are going and we will confirm which of these apply, and how current they are.

Verification

Come And Watch It Run

A video walkthrough of the production hall, the coating line, the laboratory and the packing area, scheduled against a running line rather than a parked one. Or read which audits already run over this site.

Book A Video Tour Audit Records

Enquiry

Ask For The Process Sheet For Your Model

Send the item number and we will confirm the machines it runs on, the checks recorded against the batch and the test reports that apply.

Ask For The Process Sheet For Your Model

Send the item number and we will confirm the machines it runs on, the checks recorded against the batch and the test reports that apply.

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