The Simulation Research Of Bottom Spray Quenching Technology

27SiMn steel tube is the key component of hydraulic support, while the Heating Processing plays an important role to ensure the mechanical properties of steel tube. Bottom spray quenching(BSQ) is a new type of quenching technology, which has been studied with Finite Element Method(FEM) in this paper.The flow field of quenchant and the temperature field of work-piece have been simulated with FEM, during which the technology of fluid-solid-hot multi field coupling has been taken into considered. Convective Heat Transfer Coefficient(CHTC) curve of the BSQ has been obtained for the first time, and the curve has been compared with other quenching method. The result shows that it is almost directly into the boiling stage, and has no vapor blanket stage. the BSQ have a strong cooling capacity.The flow velocity around the wall is an important factor to illustrate the cooling capacity of quenchant. The research shows that the flow rate which distances from the tube wall 10 mm is monotonically increasing. The temperature of core area of tube wall decreases slowly and smoothly. The temperature variation process of surfaces of tube wall can be divided into three phases, which are quick drop phase, step-shaped transition phase, and stable cooling phase.To improve the cooling uniformity of BSQ, the structure of quenching tank has been studied from three aspects, which are the inflow direction of water,the flow area ratio between the inside and outside of tube surface and variable diameter quenching tank, The result shows that the variable cross-section quenching tank is more superior than the uniform diameter quenching tank, whether on the cooling uniformity of axial or the cooling uniformity of the inside and outside of tube surface.