圆锥破碎机磨损模型英文文献和中文翻译

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Abstract Cone crushers are used in the aggregates and mining industries to crush rock material. A model to predict the worn geometry of cone crushers was previously developed. In that model there was some disagreements between predicted and measured geometry and several effects were suggested to explain the discrepancy in the model. In this study the effect of shear forces along the crushing surfaces was implemented in the model. Simulations were compared to measurements on two different crushing chambers. The results show a signiﬁcant improvement with respect to the discrepancy between measured and simulated geometry. Measurements were made on a coarse crushing chamber where the operating parameters hydroset pressure, power draw and capacity were tracked during the lifetime of the set of liners. The simulated operating parameters show some agreement with measured data, but the crusher was not run under ideal conditions at all times. 43856

1.Introduction

Cone crushers are widely used in the mining and aggregates industry to crush blasted rock material. The two main crushing parts are the mantle and the concave. The main shaft of the mantle is suspended on a spherical radial bearing at the top and in an eccentric at the bottom. A hydraulic cylinder supports the thrust bearing that carries the thrust force of the main shaft. The hydraulic system can raise the main shaft in order to compensate for the wear of the mantle and concave.

The hydraulic pressure in the cylinder that supports the thrust force from the main shaft is called the hydroset pressure. As the eccentric is turned the rock material will be squeezed and crushed between the liners (see Figs. 1–4).

Along its path through the crushing chamber, a rock particle will be subjected to several crushing events. The shortest distance across the crushing chamber is called the closed side setting, CSS, and is an important variable for the performance of the crusher. The control system is calibrated regularly to maintain a constant CSS. Previous research has made it possible to model the behaviour of a given cone crusher. Evertsson developed a ﬂow model, a size reduction model and a pressure response model.

The geometry of the crushing chamber is crucial for the performance. Due to wear the geometry of the liners will change,and hence the crusher performance will also change and sometimes suffer. Therefore it is desirable to simulate the change of geometry and performance as the liners wear. A model for this purpose was previously developed . That model was based on the results of Evertsson . In the model for wear prediction there was some discrepancy between the simulated geometry and measured geometry in the upper part of the crushing chamber. Several explanations of this discrepancy were suggested.It was ﬁrst assumed that the work hardening behaviour of the liner material might depend on the applied pressure. In a study by the author it was concluded that it was not a variation in work hardening in the chamber that caused the discrepancy in the wear model.

Among the other explanations for the discrepancy, that were proposed by Lindqvist and Evertsson,the prediction of pressure on the liners was assumed to be an important factor. To address this, an improved ﬂow and pressure model was presented by Lindqvist and Evertsson. That model showed a signiﬁcant improvement in prediction of the operating parameters CSS,power draw and capacity, but only a slight improvement of wear prediction for a ﬁne crushing chamber.

Other suggested explanations are non-linear dependency between pressure and wear, shear stress at the interface between rock and liner, dependency between particle size and wear rate. Chenje and Radziszewski showed that there was a non-linear relationship between applied force and wear rate in a sliding wear experiment. If Chenje’s results were also applicable for the case of non-sliding wear in cone crushers, they would, at least in part, explain the discrepancy. The technique used in the present study, to measure the geometry of the liners, is similar to the technique used by Rosario . He has made measurements of liner wear on gyratory crushers.