33kg/m槽型护轨的感应热处理研究

Study on inductive heat treatment for 33 kg/m channeled guardrail

采用33 kg/m护轨用槽型钢制造的槽型护轨在道岔中得到广泛应用,但目前无法直接利用现有的道岔尖轨热处理装置和工艺对其进行热处理。本文比较了槽型护轨和其他类型护轨的结构特点及技术标准对各类护轨热处理性能的不同要求,提出了槽型护轨热处理方案,即通过设计和制造槽型护轨专用的感应加热线圈和定位导轮,在现有的道岔尖轨热处理设备上进行槽型护轨的感应热处理。对热处理后槽型护轨的硬化层硬度、深度和金相组织进行检测,结果表明各项性能指标达到标准《33 kg/m护轨用槽型钢》(TB/T 3110—2005)的要求。

33 kg/m channels for guardrail are widely used in turnout. They cannot be inductive heat treated by the present equipment and technique for switch rails yet. In this paper,the structure and technical requirement of heat treated channel for guardrail and other types were compared,and the method of inductive heat treatment for channel guardrail was proposed. With a designed inductive coils and guide wheel dedicated for channel guardrail,inductive heat treatment of channel guardrail was conducted using present inductive heating equipment for switch rails.Through the test of hardness,depth of hardened layer and microstructure,it revealed that the channel guardrails heat treated with this method meet the technical requirement of TB/T 3110—2005.