Design And Research On Single Spiral Cutting Head Of XTR260 Tunnel Boring Machine

With the rapid development of modernization of our country,some major engineering projects,such as water conservancy,transportation,resource development etc.,are increasing progressively,and there are large quantities of constructions of tunnels included,which leads to vastly increased demand of tunneling equipment.Boom-type tunnel road header has been widely used in mining,water conservancy,tunnel traffic,urban subway and other major engineering projects,due to its wide universality,wide scope of operation,reducing labor intensity effectively,high efficiency,shortening the project cycle and other advantages.At present,domestic boom-type road headers,mainly used in the coal mine roadway construction,can't be directly used in the tunnel construction,and there are few of boom-type tunnel road headers in our country,which causes the demand for tunnel construction can't be met.In order to meet the growing demand of tunnel constructions and breakthrough the foreign monopoly of market and technology,research and development on boom-type tunnel road headers are extremely urgent.Cutting head,being the core component of boom-type tunnel road header,has important effects on working reliability,efficiency,economy and other whole machine performance,therefore,its performance provides important references on the evaluation of machine performance.The design and research on cutting head is the top priority in the research and development of boom-type tunnel road header.However,it's still lack of scientific and systematic methods and routes on designing cutting head,which leads to high load,large differences of loads,big load fluctuation on picks,short and different lifetime of picks,high energy consumption and low efficiency and other bad results.It must be particularly stressed that there are few research on the cutting head of boom-type tunnel road header,which lack of theoretical foundation and test guidelines.A lot of problems,in geometric structure parameters,installation parameters,arrangement parameters and working condition parameters and high hardness rock etc.,are still left to solve.In order to reduce energy consumption and spoilage of picks and improve cutting efficiency,this paper takes the cutting head of the hard rock tunnel boring machine as the research object,and takes the different solid coefficient and the rock with no fissure as the cutting object.Taking the technical means of Pro / E-Ansys-LS_Dyna3D joint modeling and solving the problem,the related research work is carried out,which mainly includes the following contents:(1)The mechanical properties and failure criterion of the rock and the breaking mechanism of the cutting head of the roadheader are studied.The influence of the structure,installation,arrangement and working parameters on the cutting performance is analyzed to design the geometric structure of the cutting head.The movement characteristics of the cutting head are analyzed.(2)The numerical simulation theory of simulated cutting rock is studied,and the whole process of Pro / E-Ansys-LS_Dyna joint modeling is introduced.The key problems in joint solution technology are studied deeply to ensure that the numerical simulation of cutting rock is reliable and accurate.(3)The parameters of cutting parameters of different hardness are studied,and the evaluation indexes of cutting performance are clarified: torque and its fluctuation coefficient and cutting ratio energy consumption.The influence of the spiral angle and the hardness coefficient of the rock on the cutting performance is studied by the variance analysis of the orthogonal test.The influence of rock hardness coefficient on cutting performance is studied,and the optimum rock hardness coefficient matching is determined.(4)The helix equations of the cuttings on the cutting head are studied,and four kinds of cutting head models are established.The effect of the spiral angle on the cutting performance is studied.The optimal spiral angle matching under different hardness rock is analyzed and evaluated under the evaluation index with cutting energy consumption,torque and its fluctuation coefficient as the priorit.According to the above research,the cutting head of XTR260 is finally designed out.