| The full-section tunneling machine is a machine capable of uninterrupted tunneling.It has large tunnel construction equipment with functions of rock excavation,support and propulsion,slag transportation and anchor support.It is mainly composed of a cutter head cutting system and support-propulsion-Composed of auxiliary systems such as stepping system,muck conveying system and anchor support.Anchor rod drilling rig is the construction equipment of the bolt support system,and the drill rod is a key component of the normal operation of the anchor rod drilling rig.The working conditions of the slender drill rod during the high-speed rotation work are relatively complex,and the direct contact between the drill bit and the rock is likely to cause wear and failure of the drill bit.Therefore,it is very important to use ANSYS software to study the static and dynamic characteristics of the drill rod and drill bit.significance.During the tunnel excavation process,the rock broken by the cutter head will generate strong vibration.Therefore,the dynamic analysis of the drill rod of the anchor rig is carried out to determine the natural frequency of the drill rod to prevent the drill rod resonance from causing the drill rod to break.In order to explore the static and dynamic characteristics of the drill pipe and drill bit,optimize the structure of the drill bit,improve the chip removal efficiency of the drill bit,and extend the service life of the drill rod,the main work carried out in this paper is as follows:(1)For different supporting objects,the rotation speed and thrust of the bolt rig are different,and the working parameters such as the feed thrust,torque and rotation speed of the bolt rig in hard rock are determined to provide the following finite element analysis According to this,the structural design of the luffing mechanism,the rotating mechanism,the propulsion mechanism and the host system of the anchor rod rig is carried out,and the three-dimensional model of the anchor rod and the drill bit is established in the SOLIDWORKS software.(2)Import the model into ANSYS Workbench for static analysis,and obtain strain cloud diagram,stress cloud diagram and total deformation cloud diagram of drill pipe and drill bit.Because the drill bit is subjected to rock crushing reaction force and reverse moment and other forces,the drill bit deforms greatly,and the deformation amount of the drill rod increases from the lower end to the upper end of the drill rod.The maximum deformation amount is 0.7265 mm at the drill bit,and the maximum strain It is 394.72 Mpa,and the overall deformation is relatively small,which does not affect the normal operation of the bolt drill.(3)Aiming at the problem that the resonance of the drill pipe will cause the resonance of the drill pipe when the excitation frequency is the same as the natural frequency of the drill pipe,if the resonance occurs,it is easy to cause serious deflection of the drill pipe during work,resulting in irregular drilling and even drill pipe breakage Failure.Therefore,use ANSYS software to conduct free modal analysis and constrained modal analysis on the drill pipe,and explore the influence of the length of the drill pipe on the natural frequency at a certain diameter.If the length increases,the natural frequency decreases;at a certain length,the diameter increases Then the natural frequency of the drill pipe increases.The natural frequency of the main stage of the drill pipe is obtained through modal analysis,and the resonant frequency region is avoided by adjusting the rotation speed of the bolt drill.Through dynamic analysis and research,the service life of the bolt rig can be extended,and it is of great significance to prevent resonance during the actual drilling process.(4)Topological optimization is used to analyze the drill bit and optimize the structure of the drill bit.The key force part of the bolt drill is defined as a non-optimized area.According to the analysis results,an optimized plan is proposed.After optimization,the cross-sectional area of the chip removal channel is increased by 36.11 %.The simulation analysis of the structure after the optimization program was conducted again.The results showed that the maximum stress after optimization was 280.14 Mpa.The optimized model improved the chip removal ability of the drill bit and accelerated the drilling speed of the drill bit. |
PDF Full Text Request