Research On The Mechanical Behavior Of The Packer Under High Temperature

Currently,thin layer and small spacing technique of injection production process in the main oilfields of our country develops rapidly,when the development of the well drilling and the well completion process is aiming at the high temperature,high pressure stratum and the deep well even the extra deep well and the thermal production well.The packer,whose mechanical behavior under high temperature can impact the effect of the injection production,is a key component to get oil layer sealed and isolated in oil well and water well.What above expresses the reason why the mechanical behavior and application of the packer under high temperature is becoming more and more urgent.We discussed in this paper about the research status and history of development on mechanical behavior of rubber.We discussed the theory basis of hyperelastic to analyze the mechanical behavior of packer rubber,the mathematics equations of common constitutive model,the contact and friction between rubber and tube,and finally the basic principle of sealing.After that,we gave a specific sealing principle.Aiming at the commonly used compression type packer rubber,the oil immersed experiments under different temperature and the uniaxial tensile test were conducted,which was completed with universal tester,with large deformation condition and under different temperature.After the test,the stress / strain curve of four rubber,which was immersed by oil with different temperature,was obtained.The test data could reveal the variation tendency of the stress / strain curve from different rubber under different temperature.The material fitting process,used the test data,was conducted for different constitutive model.The hyperelastic constants came from different constitutive models under large temperature range,with which the fit constitutive model for rubber under different temperature were selected as Yeoh.The FEM model of packer was set,where the rubber was described with the hyperelastic constants mentioned above.The numerical simulations for packer were carried out,the result from which was composed of the varying patten of friction force,contact force,compression distance of packer after setting under different temperature from different constitutive model.The setting and friction test of packer under different temperature were conducted.The result of laboratory test verified the result of numerical simulation on high temperature.The result mentioned above could give some theory basis for oil immersed rubber of compression packer under high temperature.