Research On Application Of Pipe Thruster Of Horizontal Directional Drilling Technology

With the continuous increase of the construction length of underground pipe network in China and the increase of long-distance large-diameter pipe-laying engineering,the horizontal directional drilling technology has experienced accidents such as insufficient dragging force,easy breakage,and collapse.In response to this phenomenon,relying on the national science and technology project "Research and Application of Pipe Thruster",this paper studies the application of the pipe thruster.It can be used in the horizontal directional drilling pipe laying project.With its powerful push-pull ability,it can assist in the back-towing stage of the pipeline.This paper mainly discusses the structure and function of the pipe thruster equipment,including the supporting and pushing device,the Pipe tightening device and the control device.The application of the Pipe Thruster machine in the horizontal directional drilling pipe laying technology is discussed,and the feasibility of the auxiliary pipe pushing process is costed.In the middle distance crossing,the pipe thruster cooperate with the small rig can reduce the cost by about 13%;In the large pipe diameter crossing above 1000 meters,the pipe thruster with the small rig machine can reduce about 20% of the costs compared with traditional method.In this paper,the existing back-towing calculation model is analyzed and compared,and the stress of the pipeline in the back-towing phase is analyzed.Based on the theory of the bending section winch effect,the predictive calculation method of the pull back force is proposed.the software were compiled by using the GUI interface of MATLAB.Based on the assumption of the calculation model,this paper simulates the force of the pipeline back in the back-towing stage.Mainly using ABAQUS software,multiple sets of simulation tests were carried out on the different load ratios of auxiliary push force and back pull force,and reliable comparison data were obtained.The simulation results show that the auxiliary pushing force has obvious effect on reducing the tensile stress and strain of the curved section of the pipe.In addition,as the load ratio of the auxiliary pushing force increases,the stress value inside the bending section of the curved section was increased;during the same effective working time,the pushing force can make the pipeline a larger displacement value than the back pulling force.