Hard anodising line for aluminium parts

Hard coat anodising plays in a different league from decorative profile anodising: an oxide layer of 20–50 μm (standard anodising typically tops out around 25 μm), with hardness approaching hardened steel and wear resistance good enough for metal-on-metal duty. It is also a different market — instead of 6-metre architectural profiles, the racks carry precision aluminium parts: hydraulic rods and cylinders, pneumatic components, automotive parts, chiller and heat-exchanger elements, defence and aerospace hardware.

The process physics is demanding. The thick layer grows at a current density of 2.5–4 A/dm² — several times higher than decorative work — and the bath has to be held between -5 and +5°C, otherwise the coating comes out soft and porous. We say it plainly: at these currents the tank heats up fast, and the chiller with titanium heat exchangers is, next to the rectifier, the largest single item in the investment and a permanent energy cost. Any quotation that glosses over cooling is mis-priced. A 30 μm coating takes roughly one hour, so throughput is counted in batches of parts, not tonnes per month.

The scope of supply covers process tanks with acid circulation and cooling, a water-cooled pulse rectifier, degreasing and etching stations, hot sealing, a drying oven and rack transport — manual, semi-automatic or fully automatic with a PLC-controlled overhead crane. Tank dimensions are sized to your parts, not the other way round.

The factory-standard line requires EU conformity work before operation — we describe the scope and cost honestly (CE marking of Chinese machinery) instead of promising turnkey CE. Send your part drawings and monthly volumes via the contact page and we will size the tanks, rectifier and chiller for you — a process US buyers know as hard coat aluminum anodizing (Type III).