Study On Press Forming Technics Of Mineral Microelement Licking Block

The mineral microelement licking block (to hereinafter referred to as mineral licking block) to formed mainly uses the press forming at present. Whether in theory or in the test, the research results about production process are quite few relatively. Moreover, the mineral licking block as a result of its unique nutrition function and the product characteristic, becomes a new thrifty feed which suits the development of our country's feeding culture and livestock, and receives many large-scale pastures and general herdsman's welcome. The largest plant of the production of mineral licking block is located in my district at home. Some varieties of its products are more nutritious than foreign products, but high production costs, poor product quality, low prices and small profits. In order to improve the competitiveness of domestic products, this paper focuses on one-way compaction production process, mainly to do the following:1. Based on the closest packing theory of granular materials, grain composition test of the mineral licking block was done according to the actual situation of production. First of all, the material was divided into three levels: diameter of 2mm-4.75mm as large particles; diameter of 0.05mm-2mm as middle particles; particle size less than 0.05mm as small particles according to the results of the screening material. Then, took the compressed ratio, the compacted density and the compressive strength as test index; Took them press forming under pressure 60MPa,70MPa,80MPa,90MPa respectively, and the optimal grain composition was the large particle content of 20%-25%, the middle particle content of 40% -60%, the rest of the small particle content through the analysis of variance. At the same time, the rule of the grain composition to compression, coMPacted density and compressive strength were investigated.2. The correlation of the grain composition, include between grain composition and compressed ratio, between grain composition and compression strength and between grain composition and the entire test index was investigated.3. The regression between grain composition and the compacted density was investigated. The multivariate linear regression equation of the compact density is y=1.631+0.003x1+0.083x2-0.051x4( the pressure x1, the large particle content x2, the small particle content x4 and the compacted density y).4. The press forming of the mineral licking block was investigated with orthogonal test method. Through variance analysis and trends diagram analysis, the optimal technological parameters were filling quantity 150g, grain composition 20%/50%/30% and pressure 100MPa.5. The relationship between water content and 1% of the binder on press forming of the mineral microelement licking block was studied. Water content 1%-1.5% is right considering water resistance, compacted density and compressive strength comprehensively. Moreover, press forming with high pressure takes higher water content and pressing forming with low pressure takes lower water content.6. Engineering application test, three kinds of mineral licking block production scheme comparison test was taken, the material without any binder, the material with 1% binder without grain composition and the material with 1% binder for grain composition. The results showed that water resistance, compact density and compressive strength performance had improved significantly with the material adding binder for particle composition. The optimal parameters was grain composition by large particle content, the middle particle content and the small particle content 20-25% / 40% - 60% / 15% - 40%, water content 1%-1.5%, the higher pressure according to the existing equipment, and the lower filling quantity based on ruminant lick appetite and production efficiency (now widely 5kg).7. The press forming process of mineral licking block was simulated with nonlinear large deformation elastoplastic finite element method (FEM). The unidirectional press forming process of the cylindrical mineral licking block was visualized with FEM software Msc.Marc 2007. The density distribution, the displacement and strain distribution, particles deformation and dense rule and the influence to density distribution from the friction between particles and die wall, upper punch and bottom punch was studied primarily. The simulation resultst can forecast the size of the green compact, and had good consistency with the experimental results. In addition, pressure upkeep can improve the compacted density and the density distribution non-uniform, and the advisable pressure upkeep time is 30s.