The Research Of Well Tractor Used In The Cased Oil Well

Oil is a fundamental energy that sustains the development of economy and national defense. With the gradually increasing demand for oil, the horizontal oil wells develop gradually as an important way to raise oil production. However, the logging of horizontal oil well is very difficult because of the hardness of conveying logging tools to the distal end of the horizontal oil well. As a new method for conveying logging tools, the well tractor developed rapidly because of its virtues. However, the domestic research of well tractor which is in the initial phase can't meet the requirement of the logging industry.No matter overseas research or domestic research, their emphasis is wheel-driven tractors identically which have the disadvantages of big size, great energy consumption and no function of automatic-unlocking. In view of the developing state, the article presents a new well tractor which can work on an inchworm principle and move continuously. The scheme of the well tractor is analyzed and studied deeply as well.Firstly, a new project of hydraulic-driven well tractor is presented. The project overcomes the shortcomings of no function of automatic-unlocking that the wheel-driven well tractors have. It also overcomes the disadvantage of intermittent-movement that the inchworm well tractors have. Based on the project, the structural design and force analysis are present.Secondly, in view of the special working environment, the hydraulic system is designed, including the design of hydraulic control circuit, valve block and oil tank. The project of vitta disposal is presented as well.Thirdly, the 3-D simulation model of the well tractor is designed by Pro/E and through kinematical simulation by ADAMS, the practicability and rationality of well tractor is proved in the article.At last, the capability of the well tractor is analyzed, including the capability of running over obstacles and running through curved pipe, efficiency, velocity, the capability of load, temperature rising of hydraulic system, the displacement of sliding block in oil tank. All of the analyses lay the theoretical ground for the manufacture of well tractor. The research of the well tractor is only in the basal phase and the deeply research on the application of the well tractor will be improved in the future.