新型齿槽结构磨片的设计与实验

Design and Experiment of Refining Plate with New Groove Structure

分析纤维分离磨片的作用机理,利用连续性方程及黏性流体运动微分方程,推导木材纤维原料沿齿槽二维流动的N-S方程;求解齿槽内纤维运动轨迹,得到纤维沿齿槽流动的运动规律。利用黏性流体流动能量损失计算公式分析齿槽内纤维运动能量损失,设定变化的齿刃侧倾角及齿槽宽度,从沿程损失及局部损失两方面降低纤维流动能量损失。基于纤维在齿槽内的流动规律及能量损失分析,设计具有扭转曲面齿槽结构的新型磨片,缓解周向齿区域加工强度,延长磨片使用寿命。采用新型磨片与普通磨片进行纤维解离实验,验证新型齿槽结构磨片设计的合理性;结果表明,新型齿槽结构可以明显改善纤维束堵塞齿槽的现象,新型齿槽结构磨片可以提高纤维的合格率约13%。

We studied the mechanism of refining plate separating fiber,derived of the N-S equation for the two-dimensional flow of wood fiber material in the groove by means of continuity equation and motion differential equations of viscous fluid. We solved the fiber motion trajectory in grooves,and obtained the motion law of the fiber flow along the groove. We analyzed the energy loss of fiber flow in grooves by the formula of energy loss of viscous fluid flow and set the parameters such as the bar edge heeling angle and the width of the groove,the fiber flow energy loss was reduced from both linear loss and local loss. Based on the flow characteristics and energy loss analysis of the fiber flow in grooves design a refining plate with twisting curved surface groove structure,the processing strength of transverse bar region was relieved,the service life of the refining plate was prolonged. A series of experiments were conducted for separating fiber using the new refining plate and ordinary refining plate,approved the rationality of the design of the new groove structure. The new groove structure can improve the phenomenon of fiber bundle blocking groove significantly,and the refining plate with new groove structure can increase the qualified rate of fiber by 13%.