Design And Analysis Of Thermowells For Reciprocating Compressor

Reciprocating compressor is a device that increases the gas pressure by reducing the gas volume through the reciprocating motion of the piston.Temperature is one of the most basic and important parameters in the measurement and control of reciprocating compressor.The protective sleeve(commonly called thermometer sleeve,abbreviated as sleeve)installed on the pressure vessel for temperature detection can cooperate with thermometer to effectively monitor the temperature change of compressor during operation and is widely used in petrochemical industry.However,in practical application,due to the effect of process fluid,the casing immersed in the fluid will vibrate due to vortex shedding.When the vibration frequency approaches the natural frequency of the casing,resonance may occur,causing the stress of the fluid acting on the casing to exceed the bearing limit of the casing,causing the casing to break and leak,damaging the temperature detection element inserted in the casing,affecting temperature measurement,and even causing accidents.This paper takes 4M125 new hydrogen reciprocating compressor and thermowell of 3.2 million tons/year wax oil hydrogenation unit of 40 million tons refining and chemical integration project as the research object,carries out three-dimensional modeling and option design of reciprocating compressor,and makes in-depth analysis and research on dynamics and statics of thermowell.Firstly,the research background of reciprocating compressor and its thermowell is summarized,and the main research object and content of this paper are determined on the basis of analyzing the research status of relevant literatures at home and abroad.Secondly,the selection design of reciprocating compressor is introduced.The classification,characteristics,basic structure and working principle of reciprocating compressors are described,and the three-dimensional modeling of each component in the reciprocating compressor system is carried out.The selection design of reciprocating compressor and the calculation of buffer volume are completed.The determination of compressor type and buffer volume provides the original data for the subsequent thermowell frequency calculation and dynamic and static mechanical analysis.The dynamics and statics analysis of the third pair of thermowells.According to the actual situation in the field,the buffer volume of the buffer is calculated,the classification of the thermowell is introduced,the relevant technical standards are expounded,the resonance reason of the thermowell is analyzed,and the thermowell is designed according to the standard formula.Finally,the finite element simulation analysis of thermowell is carried out.As a supplement to the standard calculation method,the performance analysis of the thermowell is more perfect and comprehensive,and a thermowell strength analysis program is formed to improve the accuracy and efficiency of thermowell design.In this paper,theoretical analysis and computer-aided engineering analysis are combined to study the thermowell of buffer,and many performance indexes of thermowell are obtained.The service life of the unit is prolonged by selecting reasonable casing materials,changing the inner and outer diameters of the casing,changing the external structure of the casing,changing the installation position of the thermometer and adding other auxiliary devices,etc.,which provides strong support for the product quality,ensures the actual safe operation of the compressor system,and has important engineering significance.