Improvement of a chain-hardening furnace by computational fluid dynamics (CFD) simulation

Hardening heat-treatment is an important operation in the fabrication of large chains for both the shipping industry and anchorage of offshore oil-platforms. This paper presents the outcome of an investigation that led to the introduction of modifications in a hardening furnace resulting in a substantial improvement and largely eliminating the problem of gradual cooling of the chain before immersion in the water-quenching tank. Comparing this with the present operating conditions, it can be concluded that redirecting the gas flow increases the gas temperature in the lower part of the furnace, which changes the chain's temperature-distribution accordingly.