High Speed Cryogenic Blasting for Rail Cleaning to Alleviate Low Adhesion

用于钢轨清洗的高速低温喷丸可降低轮轨界面的低粘附性，如果列车无法按要求停车，轮轨界面的低粘附性会引起安全问题。相关延误会导致罚款和乘客不满。不可预测的制动和牵引力是轮轨接触中粘着条件的变化。出现的波动在很大程度上与轨头上存在的污染物有关，如水(如露水或沉淀)、树叶、油、金属氧化物或磨屑。解决这个问题的一种方法是清洁轨头，以保持更一致的表面。以前的工作表明，与目前使用的水射流相比，使用干冰喷射清洗轨头具有许多好处。当干冰颗粒撞击到污染层时，它们会使其冷却，导致其破裂和脱粘。进一步的轰炸，当弹丸变成气体时发生爆炸，然后采取行动将其移除。这种方法不会留下任何残留的材料，也不会损坏车轮或钢轨。2019年秋季，一个公路到铁路安装系统与Network Rail在五条线路上进行了成功的试验。该系统现在可以推广到轨道头部处理列车(RHTT)无法通过的轨道清洁，并将在2020年秋季整个西高地线上使用。在该项目中，将在Network Rail、Northern Trains Ltd.、Stagecoach Supertram(谢菲尔德)和Nexus(Tyne And Wear Metro)等利益攸关方的支持下开展工作，开发一种至少可运行60英里/小时的高速低温清洗系统，以匹配目前RHTT的运行能力，并评估在客运列车上具有清洗能力的可行性。这将涉及调整技术，用于Nexus轨头治疗列车和北方列车有限公司客运列车的试验。开发工作将使用哈德斯菲尔德大学哈罗德大学的全轮/轨试验台(最高可运行到每小时125英里)，以找到这些车辆比以前测试中使用的更高速度的最佳应用参数。由于低温颗粒可以在火车上产生，它们的使用允许高速铁头处理平台比目前的RHTT小得多，并且它们将能够进行更长距离的清洁。

High Speed Cryogenic Blasting for Rail Cleaning to Alleviate Low Adhesion Low adhesion in the wheel/rail interface causes safety concerns if a train is unable to stop as required. Associated delays result in fines and passenger dissatisfaction. Unpredictable braking and traction is the variation in adhesion conditions in the wheel/rail contact. The fluctuations that occur are largely related to the presence of contaminants on the rail head such as water (as dew or precipitation), leaves, oil, metal oxides or wear debris. One way to overcome the problem is to clean the rail head to leave a more consistent surface. Previous work has shown that rail head cleaning using dry-ice blasting provides many benefits over the water jetting currently used. As the dry-ice pellets impact a contaminant layer they cool it causing it to crack and debond. Further bombardment, and the blast as the pellets turn into gas, then acts to remove it. This approach leaves no residual material and will not damage wheels or rails. In Autumn 2019 a road-to-rail mounted system was successfully trialled with Network Rail across five routes. This system can now be rolled out to clean rail where rail head treatment trains (RHTTs) are unable to pass and will be used on the West Highland Line to clean for the whole of Autumn 2020. In this project, with support of stakeholders such as Network Rail, Northern Trains Ltd., Stagecoach Supertram (Sheffield) and Nexus (Tyne and Wear Metro), work will be carried out develop a high speed cryogenic cleaning system that can operate at at least 60mph to match the operating capability of a current RHTT and asses the viability of having cleaning capability on passenger trains. This will involve adapting the technology for trials on the Nexus Rail Head Treatment Train and a Northern Trains Ltd. passenger train. Development work will be carried out using the University of Huddersfield HAROLD full-scle wheel/rail test-rig (which can operate up to 125mph) to find the optimum application parameters for the higher speeds attained by these vehicles over those used in previous testing. As the cryogenic pellets can be generated onboard a train, their use allows a high speed rail head treatment platform to be much smaller than a current RHTT and they will be able to clean for longer distances.