Papers by Keyword: Grinding Efficiency

Abstract: The research object is horizontal stirred mill, and I have studied six different Stirrer disc (including the trapezoidal tooth disc, the serrated toothed disc, the common disc, decagonal disc, the octagonal disc and the hexagonal disc) structure on the horizontal stirred mill grinding efficiency. The paper applied EDEM for six different forms of Stirrer disc simulation, analyzing the simulation results, it is concluded that: when the Stirrer disc structure is the trapezoidal tooth disc, the comprehensive performance of horizontal stirred grinding machine is best, with high grinding efficiency, low power consumption, provide a reference for the design of the Horizontal stirred mill.

Abstract: The low-grade ludwigite is one of the complex and refractory ores. Based on the high energy consumption and inefficient in the grinding process and according to the microwave-assisted grinding principle, this paper studied the microwave absorption property of ludwigite and researched the effect of microwave heating on the grinding efficiency of it. The non-microwaved and microwaved samples were characterized with regard to the chemical components, mineral compositions, macroscopic structure and microstructure, grinding efficiency by methods of the chemical analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM) and grain size analysis, etc. The results indicated that ludwigite, with good microwave absorption property, was suitable for microwave processing. The grindability of microwaved ludwigite was related to the microwave power and microwave heating temperature. By the microwave heating temperature attained 500~650°C, many macro-cracks and micro-cracks were produced by thermal stress between different mineral interfaces, which resulted in the decrease of strength of ludwigite and easy levigation, but the mineral compositions had no obviously changed, which would not affect the subsequent magnetic separation. It was concluded that short, high-power treatments were most effective but over-exposure of the sample led to reductions in efficiency. Under the same conditions, the grinding efficiency of ludwigite was improved 24.54% higher than untreated ore, which significantly improved the grinding efficiency and reduced energy consumption.

Abstract: The effect of Z-164D dispersant on the grinding efficiency of oolitic hematite was studied. The content of-0.074 mm in the ground product was increased by 30.15% by using Z-164D dispersant which weight was 2% of oolitic hematite compared without using any dispersant under the optimal technological conditions of the grinding aid experiment. It was considered that the content of-0.074 mm in the ground product was increased by 26.52% by using Z-164D dispersant which weight was 1%, so it was confirmed that the weight of Z-164D dispersant was 1% of oolitic hematite from the perspective of economic benefit finally. On this basis, the absorption characteristics of the Z-164D on the oolitic hematite surface which could change the pulp viscosity and the surface experience of particles were studied and the mechanism how Z-164D dispersant improved the grinding efficiency of oolitic hematite was revealed.

Abstract: The Copper-bearing minerals Powder (≤2mm) is used in conical ball grinding, the experimental study shows that the effect of the three kinds offactors on grinding efficiency is obvious. In this paper, we will start from the pulp rheological perspective to discuss why this is. In the end, the optimal conditions include the best pulp density 70%, the best mill speed 86.33r/min and the best time 4 min.

Abstract: In this paper, The Copper-bearing minerals Powder (≤2mm) in Dahongshan is used in conical ball grinding, the experimental study shows that the effect of ball material ratio on the grinding efficiency is obvious. The critical value and the optimal value range of the ball material ratio are different on different grinding stages, the feasible ball material ratio of coarse grinding is bigger than the one of fine grinding. In the test conditions, in terms of the ball material ratio, the critical value of ores’ over crushing in coarse grinding is 13, and the optimal range is 6-8, which is beneficial to the next beneficiation; while the critical value in fine grinding is 7 and the optimal range is 5-7. Although the ball material ratios are different, the change rule of grinding fineness corresponding to different particle size fractions is consistent, which can be used as a reference in the site operation optimization.

Abstract: The paper introduces the precision processing technology of grinding using magnetic fluid and presents the working mechanism of magnetic-fluid grinding. Based on Preston Equation, it also establishes a mathematical modeling for magnetic-fluid grinding, which is used to study the relationships between the effects of grinding and the variation of such technological parameters as the revolving speed of work-piece, the intensity of magnetic field, the distance between work-piece surface and magnetic center, the size of the magnetic fluid and grinding time, etc. Analysis on the grinding of Si3N4 ceramic-balls proves that the model has been well established.

Abstract: The permeated grinding wheel was a new kind of grinding wheel, which was permeated by the chemical additives and solid lubricant into the interior gaps of the grinding wheel. Therefore, the grinding wheel can form a lubrication film on the surface of the grinding wheel. This grinding wheel has some good features, such as lower grinding temperature, smaller grinding force, higher life of the grinding wheel, and can prevent the adhesion of chip onto the grinding wheel surface. The experimental results indicate that the ground surface quality and grinding efficiency have been remarkably improved for more hard-to-cut materials.

Abstract: Pyramidal structured lapping film, which has minute pyramidal structures formed by abrasive grains and adhesives on polyester films, is newly developed finishing tool[1,2]. It is said that the tool has eminent grinding characteristics, mainly, good finished surface quality because chips generated during grinding process can escape into spaces between pyramidal structures, and high grinding efficiency because new abrasive grains come out from inside of the pyramidal structures during grinding process. However, finishing characteristics of this grinding tool have not yet been fully explained.　In this research, the grinding experiments were conducted, focusing on the efficiency of grinding. The grinding forces were measured to examine the state of the surface of the tool. In addition, to improve the grinding efficiency using this tool, a method for changing the grinding load continuously while processing was used. This method was intended to enhance the effective chip generation and new abrasive grain emergence. As a result, stock removal of the workpiece was increased more than when the grinding load was kept constant. Moreover, using scanning electron microscope, this new grinding tool surface was observed, and its effectiveness was examined.

Abstract: The grinding wheel in the grinding process will surely become duller and duller. To find the reason for it is beneficial to optimize grinding process. The paper draws the graph of the Passivation process of grinding wheel by carrying grinding experiment in the condition of invariable grinding force. The curve can be divided into three parts according to the Passivation rate i.e. initial dull stages, regular dullness stages and rapid dullness stages. In the initial stages, the Passivation rate is lowest and the grinding efficiency is the greatest. The curve figure changes from concave to protruding，which is greatly different from wear curve of grinding process.

Abstract: Grinding, characterized by its high specific energy consumption, may generate high grinding zone temperature. These can cause thermal damage to the ground surface and poor surface integrity, especially in the grinding of difficult-to-machine materials. Conventional cooling methods based on large amounts of water-oil emulsions can be both ineffective and environmentally unacceptable. Here a new high efficiency cooling technology—cryogenic pneumatic mist jet impinging cooling technology is offered. It utilizes the high penetrative power of fast cryogenic air jet combined with a little quantity of 0°C water to greatly improve heat transfer effects in the machining zone. The experimental results indicated that CPMJI could offer better machining effects compared to cold air jet and traditional flood cooling method in the grinding of titanium alloy.