In order to realize energy-saving operation of heating system and reduce heating cost,high performance,high head and high reliability requirements are put forward for hot water circulating pump.Considering that the conveying medium is 130 ℃ high temperature hot water and the working pressure of the pump is 1.6 MPa,the whole shell structure is required to meet the strength demand,and the thermal deformation of each component has little influence on the variation of the component matching gap.Drawing on the experience of excellent hydraulic performance while taking into account the rationality of the structure,the hydraulic design of the impeller,suction chamber and extrusion chamber was carried out.After the design was completed,the pump performance,structural strength,thermal deformation and rotor dynamics were simulated and optimized with the help of analysis software.Through the test verification,the product meets the design requirements and customers requirements.