Research And Application Of Wellbore Treatment In JM Block Of Junggar Basin

The wellbore problems become increasingly prominent and the pump inspections become frequently in JM block of Xinjiang oilfield in Jungger Basin,while the water cut rising year by year.It was seriously affecting the status of old wells.So,the present situation and main problems of the wellbore were analyzed,and the formation mechanism was analyzed in this paper.And then,the corresponding treatment measures were studied,and the experimental results were analyzed.There was great significance to the wellbores treatment in this area,and positive significance for the prevention and control of the damage to wellbores in similar blocks.It was conformed that eccentric wear,corrosion,scaling and wax deposition were the most effective damage to the wellbores of JM block,through the method of field investigation,data analysis,theoretical calculation,sampling tests,tools development and synthesis of new formula.The causes and mechanism of these damage were different.The main factors affecting the eccentric wear were the instability of neutral point,moisture content increased,the well trajectory,casing deformation and so on.The main courses of wellbore corrosion fouling were the water cut,wellbore temperature and the pH and ionic composition of output water.The wax deposition was mainly affected by the wellbore temperature and pressure,oil and gas system components,water cut,the water content and the pipe surface roughness and wettability etc..Accordingly,corresponding technical measures have been worked out and field application tests have been carried out.To carry out liner tubing eccentric wear prevention technology,centralizer wear prevention technology,technical research and application of anti rod eccentric wear were taken out;Research on the application of corrosion and scaling of solid anticorrosive antiscale technology,multi effect anticorrosive antiscale technology and anti scaling technology of pump have been done.The research was carried out using conventional paraffin technique discussion and leakage of hot washing process and the new technology of paraffin inhibitor.Through the comprehensive management of the wellbore,consequently,the proportion of pump inspection coursed by eccentric wear,corrosion and scaling,and wax deposition were down by 31.3%,21.5%,12.5%,5% from 2014 to 2016.In the same time,there was a total reduction of pump inspection of 134 wells reduced lay.after the wellbores treatment.Thus,the technical measures in this paper showed good applicability to this area,and also provide valuable experience for wellbores treatment in similar blocks.