Design And Analysis Of Wax Removal Device For Oil Well Casing Based On Ultrasonic Technology

In order to solve the problem of paraffin blockage which is in oil well casing during oil exploitation,at present,each oil field usually use the paraffin removal technology of oil well casing which mainly includes hot oil circulation paraffin removal,chemical paraffin removal and mechanical paraffin removal.However,these technologies generally have some disadvantages,such as low intelligence,high single operation cost and high pollution to the environment.Compared with the traditional oil well casing wax removal process,in recent years,ultrasonic wax removal process has been widely concerned and applied in China,because it has some advantages such as high intelligence and low environmental pollution.However,now the application of ultrasonic technology in the field of oil well casing wax removal is not mature in China.When facing many kinds of working conditions,many existing ultrasonic oil well casing wax removal tools have disadvantages such as poor adaptability,high manufacturing cost,difficult maintenance and so on.Therefore,this text is established in solving the above problems,it is meant to design a new oil well casing wax removal device based on ultrasonic technology.So,the following work is carried out in this text:Firstly,this text is based on Huygens-Fresenl theory,establishing an integral model of nonpoint sound source(ultrasonic)sound field,and deducing three sets of characterization functions of sound pressure,sound intensity and sound field directivity.What’s more,it considers the problem of sound attenuation based on Stokes-Kirchhoff theory.Then,six groups of ultrasonic frequencies which is commonly used in industry are selected,and the numerical analysis software that are Comsol and Matlab are used,and it carries out numerical calculation and simulation analysis respectively on the relationship between them and the above representation function acoustic attenuation phenomenon,and determines three groups of ultrasonic frequencies suitable for different operating conditions.Secondly,based on the research of ultrasonic sound field theory,it confirms the process route of ultrasonic oil well casing wax removal.And based on this process route,it designs an ultrasonic oil well casing wax removal device which can be applied to different operating conditions.Then,it uses the finite element analysis software Ansys-Workbench.And under working state,for the possible vibration response of the designed device,it carries out Modal Analysis and Harmonic Response analysis.The analysis results show that: The natural frequencies of the key components and the whole device in this device are far less than the three groups of ultrasonic frequencies suitable for different operating conditions which are selected in the previous text.Therefore,the device will not cause structural failure as the excitation of the vibration source in actual operation.Finally,according to the device which is designed above,processing the experimental prototype and built the relevant experimental platform it carries out the test for the paraffin removal effects.It includes ultrasonic power,treatment time and temperature of the device.Based on the experimental results,it proposes ultrasonic frequency selection suggestions in view of the conditions of different oil well casing paraffin removal operation and requirements.