Materials / Structure

Heavy welded conveyor chain pins and bushings are machined from low-carbon weldable case hardening steel. To achieve best possible wear resistance, pins and bushings are case hardened. During case hardening process base material is through-hardened and additionally extremely wear resistant layer is formed onto surface of pin and bush. It is noteworthy that as a result of case hardening process also inner diameter of bush receives an wear resistant layer.

Besides the mechanical wear, conveyor chains are often exposed to corrosion and for example in many fuel feeding conveyors corrosion is bigger concern than the actual mechanical wear.

Heavy-duty welded conveyor chains have tight press fitting between pin/bushing and link plate. The shoulders of the pins and bushings ensure high dimensional accuracy and correct lateral gap while increasing the joint strength. Already strong structure is secured with V-braze weldings.

Ketjurauma has developed an unique induction hardening method to significantly increase wear resistance of side plate sliding surfaces. Unlike quenching and tempering, induction hardening has no effect on chain plate pitch and press fitting dimensions. I other words, great dimensional accuracy is maintained even after the induction hardening process.