A convex pattern surface is proposed and optimized to mitigate the sliding wear of bulk handling equipment caused by interaction with bulk solids. This work investigates the effectiveness of the convex pattern surface on wear reduction during interactions with non-spherical particles. Multiple representative particles, obtained through a sampling method, are reconstructed using a photogrammetry technique. Two contact parameters between particles are calibrated through shear box and drawdown tests to ensure flow behavior similar to the real material. The numerical results indicate that the convex pattern surface can effectively reduce wear compared to a plain sample when involving both spherical and non-spherical particles. For a plain sample, the wear volume remains independent of particle shapes and increases linearly with numerical revolutions. For the convex pattern surface, the wear volume demonstrates a quadratic relationship with the test revolutions as the deformation of convex elements weakens the effectiveness of the sample on wear reduction. The particle flow behavior analysis reveals that the convex pattern surface experiences the lowest wear volume when in contact with non-spherical particles. This can be attributed to the non-spherical particles sliding shorter distances and rotating with higher angular velocities on the convex pattern surface.

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A convex pattern surface has been proposed and optimized to reduce sliding wear of bulk handling equipment by adjusting the flow behaviour of bulk material. This study aims at modelling the surface deformation of the convex pattern sample to investigate how effectively the sample reduces sliding wear. Archard wear model and a deformable geometry technique are combined to capture the sample deformation. A short-time laboratory wear experiment is performed as a benchmark to validate the numerical model. The simulation resutls indicate that there is a linear relation between the wear volume of a plain sample and the simulated revolutions, while the convex pattern sample has a quadratic trend. The wear distribution displays that the convex pattern accounts for the majority of wear of the sample. The contact behaviour demonstrates that the convex pattern facilitates the rolling of particles, resulting in the reduction of sliding distance. The numerical results indicate that the deformed convex pattern sample leads to lower overall sliding wear than a plain sample, although its effectiveness weakens as wear evolves.

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The pin-on-disc test is a standard sliding wear test used to analyse sliding properties, including wear contour and wear volume. In this study, long-term laboratory test performance is compared with a short-term numerical model. A discrete element method (DEM) approach combined with an Archard wear model and a deformable geometry technique is used. The effect of mesh size on wear results is evaluated, and a scaling factor is defined to relate the number of revolutions between the experiment and the numerical model. The simulation results indicate that the mesh size of the disc has a significant effect on the wear contour. The wear depth and wear width follow a normal distribution after experiencing a run-in phase, while the wear volume has a quadratic relation with the number of revolutions. For the studied material combination, the calibration of the wear coefficient shows that the wear volume of the pin-on-disc test accurately matches the simulation results for a minimum of eight revolutions with a wear coefficient lower than 2 × 10−11 Pa−1@en

Bulk handling plays a significant role in a range of industries, such as the mining, agricultural, chemical, and pharmaceutical industry. For the mining industry, economic development results in an increasing demand of steel and consequently the raw materials used for steel production, such as cokes and iron ore. Dealing with bulk material leads to severe wear on bulk handling equipment due to the countless contact between materials and equipment surfaces. The wear causes surface deformation and deterioration of handling equipment, bringing a high risk of reduction in the lifespan of equipment....@en

Sliding wear of bulk handling equipment (e.g., shovel bucket, mill and transfer chute) can be dramatically reduced by using a convex pattern surface compared to a flat surface, by adjusting the flow behavior of particles moving along the convex pattern surface. To study the effect of particle size relative to the dimensions of the convex pattern surface, a coarse graining technique is applied. Comparisons of bulk flow and wear behavior between the convex pattern and flat surfaces illustrate the two-sided effect of the convex pattern surface on sliding wear. The bulk flow behavior indicates that the particle size has a minor effect on the velocity and angular velocity of particles for the flat surface, while it has a significant effect on those of the convex pattern surface. The wear results show that the particle size has negligible influence on the sliding wear of a flat surface and a linear relationship with the sliding wear of the convex pattern surface. The convex pattern surface can reduce the sliding wear through influencing the flow behavior of the bulk material when the equivalent radius of the convex is larger than r50 of particles. This research reveals the relationship between the dimensions of the convex pattern and the particle size on the sliding wear caused by the interaction between bulk material and bulk handling equipment. The relationship should be carefully considered for the applications of the convex pattern surface to bulk handling equipment.@en

A previous study revealed that a convex pattern surface can reduce sliding wear of a transfer chute. A convex pattern surface is a flat surface outfitted with a pattern of convexes defined by five parameters. A three-level definitive screening design (DSD) method combined with discrete element method (DEM) is used to investigate the influence of the five parameters and two operational conditions on the sliding wear. Two flow regimes are distinguished, namely continuous and discontinuous flow regimes, and both flow regimes can significantly reduce the sliding wear. The particle velocity and angular velocity profiles verify the guiding and rolling effect of the convex pattern on the motion of particles. A regression model fitted based on the DSD indicates that three main factors and one interaction have significant influence on the sliding wear.

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Using bionic surface on the material equipment interface of bulk handling equipment is a promising solution for wear reduction. A bionic surface is a flat surface outfitted with a pattern of convexes that disrupt the natural sliding flow of bulk material. Previous numerical work has shown a significant reduction of wear of bionic surfaces compared to a smooth surface. The aim of this paper is to study the influence of bionic configurations on wear reduction. Four geometric parameters were introduced to define the shape and size of these convex patterns. The geometric convex patterns were evaluated with the aid of Discrete Element Method (DEM). The simulated material was iron ore with d50 of 10 mm sliding down a smooth chute transitioning into bionic surface of different geometric configurations. Hertz-Mindlin (no slip) model and Archard wear model were implemented to calculate the sliding wear volume. The experimental plan was based on a full factorial design, which varied the parameters of a0, a0:b0, c0 and d0. Simulation results show that different patterns of convexes have different influence on wear volumes and velocities of particles. The factors a0 and d0 of each pattern have significant influence on sliding wear, while there are insignificant interactions between geometric parameters. It is found that the existence of convex patterns makes the particles closest to the chute’s surface have the tendency to slow down, causing the remainder of the particles to slide and roll over these bottom particles instead of sliding directly over the surface.@en

Using bionic surface on the material equipment interface of bulk handling equipment is a promising solution for abrasive wear reduction. A bionic surface is a flat surface outfitted with a pattern of convexes that disrupt the natural sliding flow of bulk material. Previous numerical work has shown a significant wear reduction of bionic surfaces compared to a smooth surface and revealed the effect degrees of geometric parameters and the interactions between them. The aim of this paper is to design samples with an optimal convex pattern for steel plates of 100 mm by 100 mm to verify the simulation results in a test rig for industrial scale experiments in Newcastle, Australia. In order to find an optimal convex pattern, a stepwise optimization, one-factor-at-a-time, is performed by optimizing four parameters of convex patterns. The geometric convex patterns were evaluated with the aid of Discrete Element Method (DEM). The simulated material was iron ore with d50 of 4.6 mm sliding down a smooth chute transitioning into bionic surfaces of different geometric configurations. Hertz-Mindlin (no slip) model with the Archard wear model were implemented to calculate the sliding wear volume. Considering the direct relation between the dimensions of convexes and the sizes of particles, the ratios of a0, b0, c0 and d0 to d50 were used for analysis simulation results. The results show that a chute surface with circular convexes with a radius of 6 mm (a0:d50=1.3), spaced 25 mm apart in both horizontal and vertical directions (c0:d50=5.4), is optimal in reducing wear. This sample configuration and smooth surface will be tested to verify the predictability of the simulation approach.@en