In response to the issues of roller surface peeling and chunk falling in the service process of heavy-duty 70Cr3Mo forged support rollers

a comprehensive study was conducted from three aspects: selection of surfacing materials

optimization of surfacing processes

and design of process equipment. Firstly

through methods such as fracture macro morphology analysis

physical and chemical analysis

and metallographic analysis

it was determined that the main cause of roller surface peeling is delamination caused by fatigue crack propagation. Secondly

based on the weldability and high-temperature performance of 70Cr3Mo steel

key process parameters such as preheating temperature

heating rate

intermediate heat treatment

and final heat treatment were determined

and SW-type ultra-low carbon Cr-Ni-Mo-V martensitic alloy steel material was selected for surfacing. Finally

a multifunctional insulation cover and a four-gun surfacing device were designed to ensure the implementation of the large-thickness submerged arc surfacing process. The research results show that this process can effectively restore the dimensions of the support roller

improve its strength

hardness

and impact performance

and make the service life of the repaired support roller reach or even exceed that of the new roller. The research results have been successfully applied to the surfacing repair of 154-ton heavy-duty support rollers

achieving the remanufacturing of waste support rollers.