Study on brazed diamond grinding wheel for rail grinding
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摘要: 为解决传统树脂砂轮打磨钢轨时存在的打磨效率低、易烧伤钢轨和粉尘污染大等问题,分析利用钎焊金刚石技术的优势制备新型钢轨打磨用砂轮的可行性。结合磨粒有序排布工艺,制备具有开槽结构的新型钎焊金刚石砂轮,并对U71Mn钢轨钢进行打磨对比试验。结果表明:相较于树脂锆刚玉砂轮,新型钎焊金刚石砂轮能提高50%左右的打磨效率,并有效降低磨削温度,避免钢轨烧伤。在钢轨打磨过程中,新型钎焊砂轮排屑效果显著,基本不发生磨屑黏附现象;但砂轮开槽导致磨削振动增大,加剧金刚石磨粒破碎,并增大钢轨表面粗糙度。新型砂轮磨屑多为带状,磨屑体积大且无熔融小球。Abstract: In order to solve the problems of low grinding efficiency, easy to burn rail and large dust pollution, when grinding rail with traditional resin wheel, the feasibility of taking advantage of brazed diamond technique for preparing a new rail grinding wheel was studied. The brazed diamond grinding wheel with slotted structure was prepared by using of the diamond orderly arrangement process. The comparative grinding tests were carried out on U71Mn rail steel. The results show that compares with resin corundum grinding wheel, the new brazed diamond grinding wheel can improve the grinding efficiency by about 50%, effectively reduce the grinding temperature and avoid rail burn. The new grinding wheel has remarkable chip removal effect in the process of rail grinding, and there is almost no chip adhesion. However, the slots on the grinding wheel increases the grinding vibration, aggravates the breakage of diamond abrasive particles and increases the surface roughness of rail. The grinding debris of the new grinding wheel is mostly band-shape with large size but no molten balls.
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Key words:
- rail grinding /
- brazing diamond /
- structural optimization /
- grinding efficiency
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表 1 砂轮相关参数
Table 1. Grinding wheel related parameters
编号 磨粒
类型结合剂
类型磨粒排布 是否开槽 A 锆刚玉 酚醛树脂 多层无序 否 B 金刚石 Ni–Cr钎料 单层有序 否 C 金刚石 Ni–Cr钎料 单层有序 是 表 2 打磨参数
Table 2. Grinding parameters
参数 类型或取值 砂轮转速 n /(r·min−1) 3 000 砂轮行进速度 v /(m·s−1) 0.1 打磨压力 F / N 600 磨削方式 干式磨削 -
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