Development and Application of Anti-corrosion and Anti-scaling Integrated Tubing String for Nitrogen Injection Machine
The wellbore and downhole tools with the nitrogen injection machine in Tahe Oilfield are seriously corroded and scaled,which is easy to cause downhole accidents such as pump sticking and difficulty in releasing packer.In view of these problems,on the basis of the existing technology,an integrated pipe string for nitrogen in-jection anti-corrosion and anti-scaling machine was developed through the optimization and improvement of struc-tural technology innovation.The pipe string includes key tools such as gas injection anti-scaling rod pump and HLR anti-corrosion packer.The structure of plunger and pump barrel is optimized and improved by gas injection anti-scaling rod pump.The upper part of the pump barrel is designed with gas injection hole,and the lower part of the pump barrel is designed with plugging cylinder.The lower part of the plunger is designed with sealing plug,and the lower part of the plunger seals the oil inlet channel during gas injection.It can prevent the high-pressure oil from flowing back into the pump chamber to cause corrosion and scaling,and eliminate the risk of plunger down failure.The anticorrosive packer adopts a new type of shoulder-protected rubber cylinder assembly and double O-ring,two-way support sealing structure,graded unsealing mechanism and split two-way slip anchoring structure to improve the corrosion resistance of the packer rubber cylinder,reduce the lifting and unsealing force and ensure the slip anchoring performance.Both the theoretical check and the indoor simulation test meet the field requirements.The field application shows that that the setting,releasing and gas injection of the pipe string are normal,and the success rate of conversion is 100％,which can meet the development requirements,solve the engi-neering problems of gas injection corrosion and scale formation of the pump and packer,and has high populariza-tion value.
nitrogen injectionrod pumpanti-corrosion and anti-scalinganti-corrosion packerintegrated pipe string
NETL
NSTL
万方数据
