Design and Development of an Unconventional Roller Test-rig for the Investigation of Rolling Contact Fatigue and Wear Phenomena in Railway Wheels and Rails

该项目的目标是设计、制造和测试一种非传统的滚子试验台，用于在“新研究仪器”计划的框架内研究铁路车轮和钢轨的滚动接触疲劳和磨损现象。提出了拟议的试验台的概念设计。该试验台旨在取代目前用于研究铁路车轮和钢轨用钢的滚动-滑动接触疲劳和磨损特性的双盘试验机。双圆盘试验机不适用于铁路车轮和钢轨材料试验中的滚动接触疲劳和磨损研究，因为它们无法复制轮轨接触中的参数。它们还遭受关于源自结果缩放的解决方案准确性的问题。用于测试真实的铁路车轮的常规全尺寸滚子测试台在RCF和磨损测试方面也具有若干缺点。提案中详细讨论了这些问题。所提出的试验台可以克服其前辈的局限性，因为它有能力测试的疲劳和磨损特性的铁路车轮和钢轨材料在接触条件接近现实。除了材料试验外，它还可用于在自由滚动、制动和加速条件下进行实际接触载荷下的一般接触研究，这使它成为一种多用途的试验台。试验台的原理是通过将试验台的滚子产生的接触斑与真实的轮轨接触斑进行比较来验证的，而不是使用模型试验台进行经验验证。这是因为，在模型试验台中不能产生用于模拟铁路车轮和轨道中的滚动接触疲劳和磨损现象所需的载荷和接触参数。有限元计算已经进行了计算的几何形状的接触补丁和其结果进行了详细讨论的建议。因此，这项申请是针对该方案的第二阶段，即制造试验台和实施试点项目，该项目分为三个工作包。WP I包括基于开发概念的试验台的详细工程设计。在WP II中，制造并调试了试验台。在WP III中，在试验台上进行了验证项目，以证明其在试样上产生预期疲劳裂纹和磨损的能力。整个项目（WP I至WP III）计划为期30个月。试验台将在验证后提供给第三方研究人员。

The objective of this project is to design, manufacture and test an unconventional roller test-rig for the investigation of rolling contact fatigue and wear phenomena in railway wheels and rails within the framework of the "New Instrumentation for Research" program. The concept design of the proposed test-rig is presented. The test-rig has been designed with an intention to replace twin-disc machines, which are currently used for investigating rolling-sliding contact fatigue and wear characteristics of steels used in railway wheels and rails. Twin-disc machines are not suitable for rolling contact fatigue and wear investigations in the context of materials testing for railway wheels and rails, as they cannot replicate parameters in a wheel-rail contact. They also suffer from problems with respect to solution accuracy stemming from scaling of results. Conventional full-scale roller test-rigs that are used for testing real railway wheels also have several drawbacks with respect to RCF and wear testing. They are discussed in detail in the proposal. The proposed test-rig can overcome the limitations of its predecessors as it has the ability to test the fatigue and wear characteristics of materials for railway wheels and rails at contact conditions close to reality. Apart from materials testing, it can also be used for conducting general contact investigations at free rolling, braking and accelerating conditions at realistic contact loads, which makes it a multipurpose test-rig.The principle of the test-rig is validated by comparing the contact patch developed by the rollers of the test-rig with the real wheel-rail contact patch instead of verifying empirically using a model test-rig. This is because, the loads and contact parameters required for simulating rolling contact fatigue and wear phenomena in railway wheels and rails cannot be produced in a model test-rig. Finite Element calculations have been carried out to calculate the geometry of the contact patch and the results thereof are discussed in detail in the proposal. This application is therefore aimed at the second stage of the programme in which the test-rig is manufactured and a pilot project is carried out.The project is divided into three work packages (WP). WP I consists of the detailed engineering design of the test-rig based on the developed concept. In WP II, the test-rig is manufactured and commissioned. In WP III, a validation project is carried out on the test-rig to prove its ability to develop intended fatigue cracks and wear on the specimens. The complete project (WP I to WP III) is planned for 30 months. The test-rig will be made available to third party researchers after its validation.