CISDI is celebrating a first for China’s coated products sector.

A Zn-Al-Mg coating able to coat steel with a composition of 11 per cent aluminium and three per cent magnesium has been created at the Lianqiang Industry Co, in China’s Henan Province, by CISDI Thermal and Environmental Engineering Co.

This composition gives coated products the best surface and alkali corrosion resistance and fracture protection currently available in China.

“Stainless-like” 11%Al plus 3%Mg coated plates produced are valuable to the light steel structure sector and can be used for high-end buildings, on 5G base stations, photovoltaic supports and highway guardrails.

Lianqiang already had two Zn-Al-Mg coating lines but, due to their inadequate systematic design and incomplete equipment functions, they could not produce high-performing medium-percentage aluminium coated products (ranging from 6 to 13 per cent).

Lianqiang was far from alone - this is seen as the most difficult technical challenge right across the continuous galvanizing and coating sector.

CISDI Thermal’s coating line design meets the exacting technological requirements for 11%AI plus 3%Mg coatings and high-strength structural steel products.

It features a number of advanced technologies, unique to CISDI Thermal, which solve historical problems such as zinc flow pattern and edge oblique pattern on the surfaces of thick-gauge, thick-coating Zn-Al-Mg products:

•      pre-oxidation for high-strength steel

•      high-efficiency cooling inside the furnace

•      snout’s rising and falling

•      snout’s gas isolation and heating

•      snout’s slag removal

•      dedicated coating roller system (to the Zn-Al-Mg coating)

•      dedicated air knife (to the Zn-Al-Mg coating)

•      nitrogen heating for air knife

•      high-efficiency post-coating regulated cooling system.

The innovative line has filled a gap in China’s capabilities for medium-percentage aluminium coatings and has led the stable production of coated plates with excellent surface quality and strong mechanical and corrosion-resistant performance.

The first coil with 11%Al plus 3%Mg coating has been discharged from Lianqiang Industry Co. It is the first production line of its kind in China.

It’s a thumbs-up from CISDI’s team as the first coil with 11%Al plus 3%Mg coating is successfully produced