The Overload Of Chemical Process Pump's Thermal And Structure Coupling Analysis And Optimization Under High Temperature And High Pressure

An overload of chemical process pump are mainly used in petroleum,chemical and natural gas industries as process pumps,and other departments that need to produce high-temperature and high-pressure fluids,medium temperature is between 150 ~ 450 ?,pressure is between 2 ~ 20 mpa.When the pump is running under such working conditions,if the structural strength and sealing performance cannot be guaranteed,it will easily cause cavitation,vibration,noise,deformation,liquid leakage and injection or equipment failure,shutdown,explosion,and fire of surrounding objects.It not only causes environmental pollution,property loss,but also endangers human health and safety.The traditional chemical process pump is designed according to the empirical formula.The most companies do not have the experimental verification conditions of high temperature and high pressure in production,but only use conventional tests to verify the strength and sealing of the pump,the rationality and reliability of the design.It not only takes a long time to research,but also has high cost,and it is difficult to guarantee the requirements of safety and reliability.Therefore,it is urgent to find an effective research method to carry out targeted design improvement for this kind of chemical process pump.This paper adopts ANSYS finite element simulation analysis method to analyze the structure and thermal coupling of a KPP series overload chemical process pump under high temperature and high pressure.It has the function of performance prediction,numerical test and fault diagnosis,and it is repeatable,which makes many complex problems which cannot be analyzed in the past and can be solved satisfactorily by computer simulation.It can not only shorten the research cycle and make the product reach the advanced design level,but also reduce the production cost of repeated trial production.The main contents of its research include:1.Based on specific temperature and stress conditions,analysis the heat transfer characteristics of existing bracket without reinforcement plate,such as temperature and heat flux distribution,and to optimize its structure,three different types of bearings are designed respectively: the bearing rack with stiffened plate,the bearing rack with cooling cavity at the end of pump cover,and the bearing rack with forced convection fan at the end of transmission.Their heat transfer rate accelerates one by one and the cooling effect is remarkable.2.Based on specific temperature and stress conditions,analyze the deformation and stress of the pump shaft,evaluate its structural strength and fatigue life,and strengthen thebearing strength of the pump shaft by optimizing the cantilever ratio and axial order chamfer.3.(1)Based on the structural design and material invariability of the existing pump body and pump cover,the temperature or pressure limit applicable to the pump in the specific industrial process device is analyzed,as well as the influence of high temperature and high pressure on the strength of the pump structure.(2)Based on specific high temperature and pressure industrial process devices,find the maximum temperature and pressure allowable under certain allowable deformation,allowable stress and limit value of safety factor of the pump with single material combination and different wall thickness,and optimize the structure form of existing products.(3)based on specific high temperature and pressure industrial process devices,find out the allowable maximum temperature and pressure of the pump body and the pump cover with the same wall thickness and different material combinations under certain allowable deformation,allowable stress and limit value of safety factor,and optimize the material configuration of existing products.The result of simulation analysis shows:(1)The high temperature has a greater impact on the pump strength than the high pressure,and the maximum deformation and stress are almost doubled.The reason is that the performance of the pump material has changed under the high temperature,from the creep of elastoplastic material to plastic brittle material,which seriously affects the strength of the pump.In the improvement,more heat-resistant materials can be selected.(2)The maximum deformation of the pump is mainly in the area of front cavity and machine seal cavity,while the maximum stress is mainly in the area of contact between the middle support seat,the rib plate and the pump body,and the area of the pump cover ring cavity.The safety coefficient of many parts is less than 1,which is very unsafe,and the wall thickness of these parts should be increased.Finally,the research method adopted in this paper will lay a foundation for the research and development of key equipment under similar working conditions.The successful implementation of the research method not only shortens the product design cycle,but also reduces the cost of manufacturing and purchasing such pumps in the industry,creating more benefits for the society.