Effects Of H-beam Rolling After Cooling On Thermal Stress

H-beam has excellent mechanical performance and widespread applications. It hasthe priority to develop as an energy saving and environmental-friendly steel. After tenyears of rapid development in China, the production and sales of H-beam are increasing.Also, product performance requirements have been more strict. The final performance ofthe hot-rolled H-beam is closely related to the rolling process, controlled cooling afterrolling steel can optimize the organization state, increase strength, and improve themechanical properties and the performance.The paper studies H-beam cooling transient temperature field and stress field byusing the finite element software ANSYS/Multiphysics. Based on the actual production,the three-dimensional model is established, spray cooling as the control cooling methodis defined, spray cooling10s then air cooling10s is set. The air cooling results shows thatH-beam can be broadly divided into three temperature zones: R angle, flange and web,their temperature reduce in turn, the maximum cross section temperature reached120°C.The stress concentrated areas locate at R and web connections. Controlled coolingsimulation results show that the H-beam overall maximum temperature is rapid cooling tothe temperature below austenite transformation. The air cooling temperature fielduniformity was improved, temperature difference is reduced to29°C. Maximum stress atroom temperature is reduced accordingly to40.1MPa, ensuring the good performanceand the organization.The analysis of relationship between temperature field and stress field shows thatcross section temperature gradient in H-beam rolling cooling process is mainly due toresidual thermal stress. Taking appropriate controlled cooling in order to reduce the crosssection temperature gradient can improve the H-beam comprehensive mechanicalproperties. The analysis result has guiding significance for the study of H-beam coolinglaw and control cooling process.