Study On Towing Capacity And Draft Requirement Of V-Plow Drain-pipe Installation Machine

The V-plow trenchless drain pipe installation machine has the advantages of simple structure,high working efficiency and low operation cost,making it particularly suitable for installation of subsurface drain-pipe in the plain areas along the Yellow River Basin.The towing capacity of the tractor and draft requirement of the plow-body are essential to the designing proceses.However,the existing theoretical and experimental studies availaboe for reference are far from adequate for developing a home-made machine.Thus the objective of this study is to explore the towing capacity of tractor and draft requirement of the plow-body at different working depth,with an aim to revel the soil-machine interaction and verify the rationality of the design of the prototype machine,and thereby to provide theoretical support for prototype improvement and new model development.The scope,methods and results of the study include:(1)Study on towing capacity.Based on theoretical analysis,three mathematical models are established for ground pressure,tangential draft and additional draft.The influence of mechanical structure,soil type and operating load on tractive performance was analyzed The maximum towing capacities under different(sandy,loam and clay)soil conditions are determined(257.51kN,295.42kN and 409.81kN).(2)Study on draft requirement.The model of draft requirement under different installation depth of drainage pipe is built through mechanical analysis.Based on the soil physical properties of the test plot,the simulation study is carried out by combining the finite element method with the smooth-particle hydrodynamics coupling method and the multi-body dynamics method.With the installation depth of drainage pipe and operation speed as the factors,the field experiment is planned with central composite design method.The rationality of the simulation regression model is verified with experimental regression model,indicating that the maximum relative error is less than 20%.(3)Verification of draft performance of the prototype.The test results show that the actual maximum operating speed at low gear is 1.35 km/h,the maximum draft requirement is 356.8 kN,and the maximum draft power requirement is 133.8 kW.Therefore,the prototype design meets the operational requirements.From the above studies,it can be concluded that the tractor has demonbstrated excellent towing performance and longitudinal stability as evidenced by the fact that resultant grounding pressure falls within the center third of the track no matter how the draft load changes.Both increasing the vertical load in sand and the height of the thorn can improve the towing capacity of the tractor.It is confirmed by field test that there exists a quadratic relationship between the pipe-installaion depth and the draft tractive force,as established in the draft requirement model.The prototype machine is in good conformance to the design requirements,with adequate towing capacity and power reserve,which suggests that the mahine can perform under even tougher working conditions.The research method and results can be used as reference for prototype improvement and new model development.