DIN 764 Chains are calibrated and tested grade 2 & grade 3 round steel chains with a pitch, t=3, equal to 3.5d, for use with chain elevators. Case-hardened chain of this type are designed mainly for applications where will be to tension.
The chains are heat treated and the surface of chain links are at least 58-62 HRc. The depth of carbonization is equal to 10% of chain diameter, with deviations of +/-0.01xd.