The main difference between WH vs WR chain (welded steel mill chain) lies in heat treatment.
WR (Welded Riveted) chains have only the pins and bushes heat-treated for basic strength, while WH (Welded Hardened/Heavy Duty) chains have all components (links, pins, bushes) heat-treated, giving them significantly higher tensile strength and wear resistance for tougher applications like heavy conveying, forestry, and sugar mills.
WH chains are superior for demanding use, while WR chains offer a more cost-effective solution for less severe tasks.
Available with riveted or cottered construction. Power-Link Catalog