MCD studied the influence of steel grade on the wear of the lining of the body of a mining dump truck for Severstal

2022: Carrying out a test to assess the wear resistance of steels of various grades

JSC Modeling and Digital Twins (JSC MCD), a supplier of domestic and foreign engineering solutions, on October 17, 2022 announced the completion of a research project for PAO Severstal. The company needed to conduct pilot tests to assess the wear resistance of steels of various grades. However, field experiments are expensive, and the dynamics of the behavior of bulk media is difficult to predict. At the same time, the issues of increasing the wear resistance of parts, replacing foreign steel brands with domestic counterparts for autumn 2022 are extremely relevant.

The experts of JSC "MCD" were faced with the task of predicting the picture and the speed of abrasive wear of two types of lining of the body of the CAT 793D dump truck, made of different grades of steel. The experts had to determine the specific wear resistance for the list of steel grades that were used in the creation of the lining. They also had to calculate their impact on body wear during operation. For the study, technological samples of iron ore and overburden rock of the coal deposit and billets of five grades of steel were taken: Powerhard 450, SD500, SD550, 09G2S and wear-resistant rolled products of a foreign supplier.

The experts of Modeling and Digital Twins JSC, together with representatives of PAO Severstal, have developed a comprehensive methodology that allows, based on inexpensive laboratory tests, to predict the rate of wear of protective coatings and working elements exposed to high-intensity abrasion. 10 pairs of "steel grade - bulk medium" were studied and the ratios of wear operation and weight loss of worn bodies were determined.

Two software complexes were used as tools for the study:

• Ansys SpaceClaim to restore 3D geometry from drawings and simplify the model;
• Rocky DEM for modeling the wear process of steel samples in the abrasive wear mill, as well as modeling the loading, unloading and transportation of ore in the Caterpillar 793D dump truck.

The work consisted of two stages. First of all, laboratory tests and DEM modeling were carried out, including:

• Calibration tests to determine the coefficients of interaction of bulk media with steel.
• Wear resistance tests. During them, samples of each of the 5 steel grades were subjected to abrasive action from the bulk media under the same conditions.

As a result, the mass losses of the plates of the studied steels were compared, as well as the wear work, on which the damage accumulated by the plates over time depends.

Further, the experts used mathematical modeling methods, including calibration tests, wear tests to determine the wear operation under these conditions and the process of loading, unloading and transporting ore with a dump truck. In total, the project used two models of a dump truck:

• A model prepared for wear of the bottom lining and rear wall of the body, on which two strips of the tested protective coating were located.
• A model prepared for wearing the lining of the side wall of the body, on which the tested coating samples were arranged in a checkerboard pattern.

The MCD JSC experts simulated loading and unloading cycles in an amount sufficient to achieve complete wear of the protective coatings of the bottom and side wall, and also recorded the work of tangent forces caused by loose media on the surface of the studied lining.

The use of DEM modeling made it possible to predict the suitability of lining from different grades of steels, compare the suitability of the protective coating of two different structures before manufacture and conduct mathematical modeling by one employee and one PC. As a result, experts determined the wear maps of the lining of the Caterpillar truck body 793D and confirmed them with pilot tests.

The project, carried out with the support of MCD JSC, allowed us to develop and implement new, more durable linings of mine dump truck bodies, to offer our customers technically and economically justified options for increasing production efficiency through the use of modern steel grades. A similar approach to the integrated application of knowledge about the properties of materials, laboratory research and computer modeling can be implemented to solve a large range of problems, "said Oleg Kopaev, head of the computer modeling team at Severstal.