| Hammer piece is the core part of the crusher.In the process of crushing the material,the hammer piece itself suffers serious wear and tear and is easy to fail because of the direct contact and interaction with the material,thus affecting the production efficiency and service life of the mill.In order to improve the grinding effect and anti-wear property of hammer piece,this paper adopts brazing method to consolidate single layer and orderly arranged diamond abrasive particles on the surface of common stainless steel hammer piece.The high hardness of diamond abrasive is used to effectively crush the material and resist the wear of the hammer sheet at the same time.Through comminution of corn grains,the effects of order arrangement,grain size and density of diamond abrasive grains on the grain size and hammer wear of corn were studied and compared with those of stainless steel hammers in common use,and the effects of grain size,grain size and density of diamond abrasive grains on the grain size and hammer wear of corn were studied.The wear characteristics,regularity and mechanism of brazed diamond hammer are analyzed.In addition,the comminution adaptability of brazed diamond hammer to Pueraria lobata and biological straw was studied,and the crushing mechanism of the material was also discussed.The main conclusions are as follows:The grinding performance of diamond hammer is better,the grain size of corn is70% of that of straight line,and the wear resistance of straight line is better,which is 1.35 times as much as that of ordered dislocation.The grain size of corn is 70% of that of straight-line uniform arrangement hammer,and the wear resistance of straight-line uniform arrangement hammer is 1.35 times as high as that of ordered dislocation hammer.The grinding property of the hammer with small diamond size is better.The crushing size of the hammer is 89.9% of that of the 25/30 hammer.The wear-resistance of the hammer with large diamond size is better,and the 25/30 hammer is 2 times higher than the 35/40 hammer.The grinding effect of the hammer with low density of diamond grains is better,the particle size of the hammer is 95.7% of that of the hammer with high density,and the wear resistance of the hammer with high density is better,which is 1.4 times higher than that of the hammer with low density.The grinding and wear resistance of brazed diamond hammer is better than that of stainless steel hammer.The wear resistance of brazed diamond hammer is improved by 7 times and the particle size of the material is finer and more uniform.The wear characteristics of diamond particles on brazed diamond hammer face arecomplete,micro-and macro-fragmentation.The macro-fragmentation at the top edge of brazed diamond hammer is more than that near the center and the positive center.The end of the hammer near the feed port of the comminution chamber is seriously worn.The wear of the hammer piece is distributed along the width of the comminution chamber and is uneven.Brazed diamond hammers wear gradually under the action of continuous front impact and eccentric friction of the material,and the diamond grains are repeatedly impacted and rubbed by the material,the reaction force of sliding appears to be slightly broken,with the increase of time.Local macro-fragmentation occurs at the part of the hammerpiece where the maximum force is placed on the hammer.Brazed diamond hammer has good material adaptability,especially for corn and Pueraria lobata,and its wear resistance is outstanding.The average grain size of corn powder can reach 30.1 ?m,the wear amount of hammer piece is only 0.35 g,the average particle size of Pueraria root powder is 38.8 g,and the wear amount of hammer piece is only 0.04 g.The comminution of peanut,corn and rice straw showed that the grain size of peanut straw was the smallest,and the grain size of rice straw was the largest,which was2.15 times that of peanut straw and 1.98 times that of corn straw.The impact force and rubbing force of brazed diamond hammer to the material can break the cohesion of the material when the material is broken,and when the corn particles are larger,the main ones are brazing diamond hammer front strike and corn particle impinging on the tooth plate and the screen plate,and the material is broken when the corn particle is larger than that of the brazed diamond hammer piece.With the decreasing of corn grain volume,the grinding form becomes the main crushing form,and the whole grain crushing of corn is irregular.Pueraria root is mainly brazed diamond hammer piece rubbing peeling and shear under the action of crushing.With the increase of crushing time,Pueraria lobata was continuously stripped into thin strips,which were completely crushed under the combined action of rubbing and shearing of hammer and tooth plates.The crushing form of Pueraria lobata was fiber-like whole strip peeling. |
