Design Of Mechanical Property Testing And Data Transmission System For Downhole Pipe String

Reservoir water injection technology plays an important role in maintaining reservoir pressure,enhancing oil recovery,increasing production and stabilizing production and improving oilfield development effect.Under the comprehensive influence of piston effect,bulging effect,bending effect and temperature effect,the stress state of the layered water injection string is very complicated in the process of downhole operation.At the same time,the change of downhole pressure and temperature will also cause the stress change and axial deformation of the water injection string,resulting in the peristaltic failure of the packer.In order to reduce the blindness of the string design and improve the service effect and life of the string,we need to accurately grasp the force and creep of the downhole string in order to improve the safety and reliability of the oil field operation.In order to accurately detect the mechanical property parameters of downhole water injection pipe string and realize the extraction of downhole data,this paper designs a mechanical property test and data transmission system of downhole water injection pipe string.First of all,the mechanical structure part of the system and the seal and other key parts of the system for the scheme design and drawing,the relevant theoretical calculation and strength check,and the mechanical part of the trial production of the finished product,the relevant ground test,to verify whether the strength of the mechanical structure to meet the safety requirements and design requirements.Secondly has carried on the related design to system circuit board related functions,the main part of sensor,controller,a memory,a power supply parts selection and related peripheral circuit design,system data acquisition,data storage and data transmission function,and the trial production of circuit board and sensor,the ground test,verify that the system circuit is qualified.Then has carried on the design to the data transmission module,the CST electromagnetic simulation software based on the well conditions to build parameterized model of underground wireless communication,thickness,width,Angle of antenna design for the dimensional parameters such as simulation,to extract the best dimension of the antenna and pipeline parameters and the optimal transmission frequency of 433 MHz,the extraction of the antenna longitudinal displacement,transverse displacement and rotation Angle and the injection fluid salinity and the influence of different parameters on the antenna signal transmission performance,and puts forward a kind of wireless communicate with cable transmission way,the data transmission module circuit design,Combined with the simulation results,a test rig is built to verify the feasibility of the underwater wireless short transmission scheme.Finally,the whole system is made,and the test is carried out in the oilfield test well site,and the test data is extracted and analyzed.The results show that the mechanical structure strength and seal design of the system meet the design requirements of no deformation,damage and leakage under the pressure of30 MPa and temperature of 80℃.The system circuit can meet the collection,storage and data transmission functions of the downhole mechanical property parameters,and the system has low power consumption,high stability,high fitting degree between the data detection results and the actual results,which meets the design requirements of the circuit system and power consumption requirements.The wireless transmission part of the data transmission system can realize good communication within the range of 60 cm,and the wired transmission part can realize data transmission within the range of 0-2000 m,so as to realize effective,rapid and stable data transmission.