Analysis And Research Of The Ability Of All-welded Ball Valve To Resist Earthquake Disaster

The all-welded ball valve is an important control component for the medium long-distance main line of oil,natural gas/shale gas and the valve control room of the branch line system.It plays a role of int ercepting and dividing the conveying medium,and its safety performance directly affects the operation safety of the long-distance pipeline system.With energy security.With the completion of the operation and construction of China's “West-to-East Gas Transmission”,“Chuanqi East Transmission” and “ Three Horizontal and Four Vertical ” Gas Transmission Projects,long-distance pipelines and supporting facilities have been achieved while breaking the foreign monopoly of key valve series products.The research on the ability of device components to resist geological disasters has become one of the important fields in the construction and operation of large-scale equipment projects in China.Although China is a country with frequent geological disasters and earth quake disasters,compared with the research and application of large-scale equipment engineering and supporting products against geological disasters in foreign countries,China started late,and the research methods,means and practical experience accumulated less.To a certain extent,it restricts the development of large-scale equipment projects in China,such as nuclear power projects.Under such a background,the research on the capability of large-scale equipment engineering system to resist earthquake disasters is put forward.This paper focuses on the large-scale all-welded ball valve series products and supporting pipeline systems for long-distance pipelines,based on the premise that the supporting pipelines do not produce critical yield limits.Transient dynamics method for modal(vibration)analysis,study the ability of large-scale all-welded ball valve products and supporting pipeline systems to resist earthquake disasters,and explore the application of transient dynamics in the study of seismic performance of all-welded ball valve series products and supporting pipeline systems The technical and effective methods provide theoretical and experimental verification basis for the formulation of large-scale all-welded ball valve series products to resist earthquake disaster safety technical specifications,long-distance pipeline valve localization and long-distance pipeline engineering construction and safe and stable operation.The main research methods are reflected in the following aspects:1)Taking DN48"FW-600 LB all-welded ball valve and pipe fitting system as the research object,using the finite element analysis and calculation method,using the transient dynamics method based on modal(vibration shape)analysis,obtain the vibration mode characteristic frequency and avoid the system.Resonance occurs,and for the subsequent transient dynamics analysis,the conditions for creating the response of the transient dynamic equation under the ground motion excitation load are effectively solved.2)The earthquake occurrence process is a typical stochastic process.How to effectively determine the ground motion load excitation and obtain the response solution of the transient dynamic equation of the research object has long been one of the difficult problems in seismic engineering research.In this paper,the main characteristic parameters of typical earthquakes in China(Wenchuan and Jiuzhaigou)are used to generate the ground motion standard response spectrum.Then,the ground motion standard response spectrum is retrieved from the PEER ground motion database to obtain two natural seismic waves that have occurred,and passed Simqke.Gr software simulates an artificial seismic wave as the load excitation of the research object with time history,adopts transient dynamics time history analysis method,introduces three major excitation factors of amplitude,frequency and time history,and uses Rayleigh damping to measure nonlinear dynamics.The equations are simplified into linear independent dynamic equations.Finally,the ANSYS Workbench software transient dynamics analysis calculation module(solver)is used to solve the time history response based on three ground motion seismic wave excitations,and obtain the time history in 1.3s.The stress characteristics of the point.3)According to JB/T4732-1995(R2005)steel pressure vessel-analysis design standard for pressure vessel classification and failure evaluation specifications,can be used for three types of pressure vessels using pressure members(acce ssories)for strength,stress,safety evaluation.The evaluation shows that the DN48"FW-600 LB all-welded ball valve and pipe fitting system has the ability to resist the Wenchuan and Jiuzhaigou seismic characteristics(8-level intensity)under the conditions of design and use,and will not cause functional failure.In summary,the methods,means and evaluation specifications of the all-welded ball valve resistance earthquake resistance analysis research conducted by the thesis have a good reference for the study of large-scale equipment engineering resistance to earthquake disasters.