Stainless steel chains for galvanization companies

Chains for hot dip galvanizers, hardening shops and pickling plants

Because of the special environmental conditions (zinc baths up to 475°C, hydrochloric or sulphuric acid baths with a concentration of 15% at approx. 30°C=86°F) only chains in special qualities and with reduced lifting capacities can be used in hot dip galvanizing, hardening shops and pickling plants. If other chains are used there is a danger of hydrogen embrittlement.

The following can be used:

1.     Chains acc. to DIN 32891 grade 2 - stress-relieved annealed
2.     Armco chains grade 2
3.     Chains acc. to EN 818-6 - 4 grade 4, with increased tempering temperature
4.     Kettenfabrik Unnas stainless sling chain system grade 5

1. DIN 32891 Quality Class 2 chains must be stress-relieved annealed for use in hot dip galvanizing.This means heat treatment at a temperature clearly above 1000°C. Here the steel's carbon content is reduced and the alloy elements from the enriched zones (segregations) are evenly distributed. This reduces the danger of stress corrosion.
2. Armco has a carbon content acc. to DIN of less than 0,03% usually less than 0,01%. This reduces the danger of intercrystalline corrosion as well.
3. Chains in accordance with EN 818-6 - 4 are heat-treated at min. 450°C, i.e. chains may only be used at temperatures up to 400°C. Because temperatures of up to 475°C are usually reached in galvanizing baths, chains for this application are heat-treated at a temperature higher than 600°C leading to a ferritic grain size of 7 or better. However, this also means a reduction of the working load limits as well.
4. The Kettenfabrik Unna stainless sling chain system is manufactured from corrosion-resistant stainless material in accordance with DIN 17440.

The safety provisions (ZH 1/323) prescribe reduced carrying capacities for all chains in order to take account of the aggressive ambient conditions. The following lifting capacities apply for single strands in Germany (for other countries please contact us)