Craft And Numerical Simulation And Reaserch Of P110Oil Case For Quenching Alternately By Water And Air

The oil casing is mainly used as supporting equipment of oil wells and gas wells,because of its poor working conditions,caseing will suffer such as bending,compression, tension and torsion combined effects of all kinds of stress,and the casingcan not be reused,this requires casing with high integrated mechanical propertiesmechanical properties.So oil casing must be quenching and tempering in production,in order to improve the oil casing integrated mechanical properties.Currently in theproduction of heat treatment,using the traditional craft as quenching process,foundcasing quenching cracks to appear,it is difficult to guarantee the quality ofcasing,causing huge economic losses to businesses.This article makes P110casing with25MnV material as the study object,on thebasis of analyzing the original tradition of quenching process(casing directlyquenching by water to room temperature),propose a new type of alternating water-airquenching method instead of the traditional cooling methods,and using finite elementmethod in numerical simulation of residual stress produced in the quenchingprocess,by combinating orthogonal method,simulate ognization stress and thermalstress of quenching process with different parameters,work out the best processparameters of casing quenching.During study, for the sizes are:244.48mm×11.99mmP110oil casing,first of all,using finite element analysis software ANSYS14.5,established a mathematical model of oil casing pipe quenching process, calculated onthe temperature field of oil casing pipe wall thickness direction,to compare thesimulation results with the actual measurement results,they matche better,verify thefeasibility of numerical models.And use orthogonal experimental method on thecomparison of different water and air simulation of quenching process of alternatingparameters,the temperature field and stress field analysis results showed that: whenthe combination of process parameters is water cooling7s,air cooling7s,again watercooling10s,thermal Stress and organizational stress of casing in the process oforganizational changing can be reduced, pipe’s residual stress can be reduced. Then toanalysis the experimental sample,observed its microstructure,results display:using this parameters combination,casing basically completed the martensitic transition,andthere is a little of lower bainite in the microstructure,and lower bainite has highstrength and toughness,will stop producing micro-cracks and curtail its expansion,andthe pipe quenching hardness reached48HRC, guarantee the quality of quenchingeffectively.The study of alternating water-air quenching method not only reduce the stress inquenched,but also can ensure the simultaneous of casing martensitic transformation ofinner and outside,can inhibit formation or expansion of quenching crack.This way ofmodeling and simulation that proposed by this article,on the analysis of casingtemperature field and stress field changing under different conditions and differentoperational parameters,provide a theoretical basis,on further analysis of heat treatmentprocess for oil casing with different sizes,different usage,it have greater referencevalue.The results of the study have great effection on improving the rate of heattreatment to ensure product quality,and increasing economic efficiency of businesses.