| Medium Density Fiberboards is one of the important inventions offorestry industry in the 1999s, its excellent performance can't be taken placeby the other fiberboards. The pace of development of Medium DensityFiberboard of China is the fastest, and China has become the productionranks. With the maturation of the technology of defiberator, the scope ofdomestic medium density fiberboard production lines is expanding gradually,but a considerable number of domestic production lines are composed ofimported defiberator, this shows that has a big gap between domesticdefiberator and imported defiberator, the refiner plate is the one of reasons.Fiber is the quality foundation of the medium density fiberboards, thegrinding process is a very important process in the whole process ,however,the refiner plate is the key of influencing on defiberator performance, thatis to say, the plate is a component to separate fiber directly, in the fiberseparation ,the plate leads to seriously wear, and the energy consumption ofdefiberator is very great. In the period of using defiberator, the replacementcost of refiner plate is even more than the acquisition cost of defiberator.Because we are lack for the key technology of plate production, themanufacturing precision of refiner plate, the structural design of refiner plate,wearability, the saving of energy, the using life etc. there is a considerablegap compared with the advanced international level. Therefore, manyfactories of manufacturing medium density fiberboards are importing refinerplates. moreover, the cost of imported equipment is very high .Therefore, weshould actively learn from foreign technology, absorb advanced foreigntechnology, and develop new, high-quality, high efficient defiberator.The refiner plate is the key part of defiberator ,its gear design andchoice is reasonable or not ,will have a direct impact on the effectiveness ofdefiberator. Therefore, in this paper, we need certify the cutting each turn ofdesigned refiner plate.The refining space is composed of a dynamic plate and a relative staticsite. When the pulp gets across the gap of two plates rolling relatively, fibercomes in for mainly the pressure and shear stress, so in the course of grinding operation, the refiner plate also comes in for the pressure andshear stress. In this paper, I make a linear static analysis by employing finiteelements analysis software, in order to ascertain whether the refiner plate inthe awful working environments can meet the demands of material andproviding necessary data for later optimization and analysis.The refiner plate works under the condition of high temperature, in thestructure of the refiner plate ,the plate will have thermal stress, and thisthermal stress often exceeds the load stress, leads to structural cracks,endangers the safety of the structure. in the course of grinding operation,the refiner plate will occur wear, make the gear low, lead to change in thedisc space. Therefore, it is very important to adjust the grinding gap timely.however, when the grinding gap is small, there is a little or no fiber, so it isdifficult to absorb friction heat, it will cause the growth of refiner plate surfacetemperature dramatically. The refiner plate absorbs a large amount offriction heat, the corresponding expansion will occur, and cause two refinerplates opposite bending deformation, the direct contact between the refinerplate will take place, which leads to a greater accumulation of heat anddeformation. Therefore, it is necessary to make a thermal stress analysis,and make understand of the thermal deformation of refiner plate.In order to meet the demand of light–duty of the refiner plate, the wholemodel of refiner plate is parameterized, with the gear highness and gearthickness of the refiner plate for the design variables, the overall weight ofplate for function, this dissertation optimizes the plate by finite elementanalysis software to ensure the model to be light-duty with the premises ofmeeting material requirements.
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