One rolling line for sheet, plate and coil in six main stages — and one finishing line for battery terminal rod Φ18 in twelve documented operations. Parameters, QC gates and equipment are listed in full so an audit can be checked off step by step.
What decides performance is the temper as much as the grade. Every annealing and cold-reduction combination ends in one specific condition: O, H1x, H2x, H3x, T4 or T6.
Charge make-up, melting at 700–750 °C, refining for degassing and dross removal, on-line spectrometer check, cast into slab.
Soaking in the homogenising furnace removes segregation and casting stress before hot rolling.
Reheated slab broken down on the hot mill into plate or hot-rolled coil.
Cold reduced to target gauge; reduction ratio sets the work-hardening level, with closed-loop thickness control.
Softening to O in batch or continuous annealers; T6 solution treatment for 6xxx; H116 / H321 stabilising anneal for 5xxx.
Tension levelling, slitting, shearing, filming or brushing; tensile, hardness and thickness reported for every batch.
Aluminium coil rod in, finished Φ18 rod out. Three operations are controlled as critical characteristics (CC), three positions carry inspection gates (QC). Finished diameter tolerance is per order — ±0.05 mm as standard.
Coil rod / billet receiving, grade & heat number verified
700–750 °C, refining & degassing, spectrometer recheck
Water quench then air blow-dry, set and dry
Straightener removes bending stress; ≤1 mm/m
Removes oxide skin and burrs
25–40 kHz, 40–60 °C, 3–5 min: de-oil & de-chip
Blow-dry before extrusion, no water film
Steady temperature, pressure & speed; uniform section
Sized through Φ18 die, ample drawing lubricant
Dimension, surface, mechanical & physical testing
Coiled neat, each coil tagged with batch number
Final check, stretch film & strapping, warehoused
| Operation | Key Parameters | Inspection Item | Acceptance Criteria | Non-conformance Action |
|---|---|---|---|---|
| 1. Raw material | Grade per order (1060 / 6063); no heavy oil, scratches | Mill cert, surface, diameter | Matches order grade and size | Return / concession review |
| 2. Melting (CC) | 700–750 °C by grade; refining & degassing | Composition, furnace log | Spectrometer result within grade limits | Composition adjustment / re-melt |
| 3. Water / air cooling | Water 20–40 °C, exit ≤50 °C | No water stain, no overheating | Dry, no oxidation colour | Isolate & rework |
| 4. Straightening | Roll gap set to material diameter | Straightness, no roll marks | ≤1 mm/m | Re-straighten |
| 5. Brush de-scaling | Moderate brush pressure | Surface cleanliness | Uniform, scratch-free | Adjust & re-brush |
| 6. Ultrasonic cleaning (QC1) | 25–40 kHz, 40–60 °C, 3–5 min | White-glove wipe test | No visible oil or black residue | Re-wash |
| 8. Extrusion (CC) | Set by die and by grade | OD, straightness, surface | Uniform section, no cracks or blisters | Scrap, trace to die |
| 9. Precision drawing (CC / QC2) | Φ18 die; tolerance per order (±0.05 mm std) | OD, roundness, surface finish | Φ18 within tolerance, no scratches | Scrap if out; trace to drawing die |
| 10. Material inspection (QC3) | Per GB/T or customer standard | 100% dimensional, sampled mechanical | Conforms to order and standard | Isolate & review; rework if feasible |
| 12. Final inspection & packing | Label: grade, size, batch, qty, date | Complete labelling, secure packing | Label matches goods | Re-label |
| Equipment | Purpose | Daily Check Points |
|---|---|---|
| Pay-off stand | Raw material feed | Free rotation, no jamming |
| Straightener | Straightening | Roll wear, gap setting |
| Brushing machine | Surface de-scaling | Brush wear, pressure |
| Ultrasonic cleaner | De-oil & de-chip | Power, bath concentration, temperature |
| Air-cooling section | Surface drying | Air pressure, nozzle blockage |
| Horizontal extruder + die | Extrusion | Die wear, temperature, pressure |
| Melting furnace | Melting & composition control | Furnace temp, flux, degassing unit |
| Water tank / air section | Cooling & setting | Water temp & level, air pressure |
| Drawing bench + Φ18 die | Precision sizing | Die bore, drawing lubricant |
| Coiler | Coiling | Neat traverse, tension |
A mandatory item in any automotive-chain audit. We run electronic batch-level records as standard and upgrade to piece-level traceability under IATF 16949.
Heat number, die number, operator and inspection data recorded for every batch and retrievable with the shipment.
Incoming, process, extrusion and melting records kept 1–2 years; final inspection data archived long term.
MTC issued with every shipment: chemical composition, mechanical properties and measured dimensions.
SGS, BV and Intertek inspections accepted on site; container loading can be video-witnessed.
We can send the process flow chart, control plan and inspection report templates together with the quotation — everything you need for supplier approval.