Development Of High-quality Disc Cutter Rings Used In TBM

The underground space development has been into the heyday in the 21 st century,while the shield construction method also has been used in the exploitation of underground space from the late 20 th century,and the tunnel boring machine has played a decisive role.The disc cutter ring directly contacts into the rocks in the work process,which is more easily wear and tear,so it will cost many rings in the construction.The costs will be improved when the cutter rings are changed frequently,and the construction cycle will be extended,so the cutter rings must maintain a good performance to use.The high-quality disc cutter ring is imported at a high price in domestic now,and domestic disc cutter ring's quality is lower than the abroad,so we are disciplined by the abroad which will limit the market of the development of the underground space at home.This paper focuses on the study of domestic high-quality disc cutter rings used by the way of simulation combined with experiment.Main study contents and results are listed as follows:1)The experiment of anatomy of the disc cutter rings have been done.The differences are contrasted at home and abroad after the anatomical analysis from the steel's purity,mechanical properties,metallographic structure and macrostructure.The test results showed that: the abroad of disc cutter rings' quality are much better than the domestic,and the manufacturing process exists differences at home and abroad.2)The hot deformation behavior has been studied about the H13 steel in the experiment.The high temperature constitutive equation was established after obtaining the curves of the stress-strain and the suitable processing parameter of the H13 steel is within 1050-1200?and the strain rate is the range of 0.01-0.1s^-1 basis of the hot processing map and metallographic structure to provide the theoretical basis and reference for the hot processing in the experiment.3)The simulation,optimization of design and trial-produce has been completed and the forging made in the experiment was anatomical tested.Based on the H13 steel's high temperature constitutive equation and the measured thermal properties,the thermo-mechanical coupling simulation for disc cutter rings' die forging processes were conducted,and the distribution of the stress,strain and temperature were obtained.The billet and mold were designed after optimization and the causes of defects were analyzed by metal flow mechanism analysis.On this basis,the design of the mold and the process of die forging are completed,and the dimension of the forging in the experiment comply with the design requirement after the trial-produce.The metallographic structure and performance were improved by the heat treatment of super-refinement.The results of the anatomy show that: the disc cutter rings' quality studied in this thesis have reached the abroad,which can be used in the TBM.