Research methods for the evaluation of the relevance of application oriented laboratory wear tests

In this work, different research methods and test procedures were examined and compared in order to have a better understanding of the relevance of various application oriented laboratory wear tests relative to the in-service performance of the steels in mining conditions. One of the important results of this study is that quite different wear events can be compared, when the wear rates are presented as the mass loss of the sample divided by the wear area, contact time, and density of the material. However, this kind of information is commonly very difficult to obtain for the in-service samples, and thus normalizing of the results with a reference material is often an easier route. On the other hand, thorough characterization and comparison of the wear surfaces and deformations is essential for the confirmation of the similarity of the wear mechanisms in different cases or different tests. In the studied case of the wear plate of a dumper truck body, several test methods were needed for the experimental simulation of the complex wear environment in the haulage of minerals.

A Study on Maintenance Free Method for Bogie of the Freight

As there are many wear parts in the bogie of freight car, the cost of maintenance is high. Also there are many problems to change the wear plates. In case of welded structure bogie, wear plates are attached 30 positions. Especially, the occurrence of the wear quantity at the side of axle box is higher than any other wear plates. Wear parts needs the low wear and high strength. But the repeated load of carbody has acted on wear parts up down direction continually, the friction force defects at their surfaces. At present, the life of wear plates at the side of axle box is about 3~4 years. So we need the new development of wear plate over ten years life to improve the durability and find the new composite material for maintenance free.

Effectiveness of Wear Plate at the Saddle Support

A theory is presented to analyze the effectiveness of incorporating a wear plate at the saddle support of a cylindrical pressure vessel. The wear plate can be either welded to the vessel or of loose fitting. The theory is based on a contact stress formulation together with the use of a cylindrical shell bending theory for simply supported cylinder. The effectiveness of the wear plate in reducing the peak circumferential saddle-horn stress is quantified by definition of a stress reduction factor. Parametric data are carried out for the saddle angle of 120 deg. From the study, the optimum thickness of the wear plate for three different angular extensions, are obtained.