Improvment And Application Of The Finite Elemet Simulating Model Of Sucker Rod

Sucker rod is the most important tool in the system for rod pumping. The real well track is a spce cure in straight well and controlled directional well.While the sucker rod moving in the well, the rod would frict the oil tube, because the rod bears much press and is stricted by the well trace. And this reduces the life of rod, even will cause rod-break accident in worst. So it is very significant for directing the optimizing design of decreasing the friction to researching the flexural law of sucker rod and forcasting the contact area and pressure and rate of friction between rod and tube. As the above-mentioned, the works are as followed:(1)Study in depth the simulation model of enviroment load of sucker rod. Improved and developed the mechanical analysis and simulative software for flexural deform of sucker rod. It includes all that: Builded the simulation model of pressure in pump and loading of pump.It considered the infulunce caused by the flowing of oil-gas-water mixture. Considered the axial vibration of sucker rod,build the realistic model. Builded the new method of auto dividing elements with the help of real structure of sucker rod. Raised the iterat method of rigid of elastica elements. All of these speed up the rate of simulation and reduce the duration from 30~90 minitues for one well to less than 5 minitues for one well.(2)Based on the simulative result of displace and pressure of node on rod, build up the simulative model of contact-area model and distributed pressure between rod and tube. Found the optimize model including unknown parameter. It provides the foundation for researching the friction rate between the sucker rod and oil tube.(3)Use the theory of tribology and based on concrete structure of rod, build up wear-efficiency model as the contact area and distributed press are known between rod and tube. Certain the maxium wear limit with the help of checking the residual intensity of worn rod and build up the forcasting model of rod under the practice operational mode. (4)Develop the software called mechanical analysis software of sucker-rod with the Visual Basic 6.0 programe language.It not only can judge the contact situation of sucker-rod and oil tube,but also can prescribe the contact area and forcast the life of sucker-rod. It will be very useful in oil field production.