冷轧组合式支承辊过盈配合面应力和微动滑移的分布及影响因素

采用ABAQUS软件建立冷轧组合式支承辊的三维模型,通过模拟带钢轧制过程获得不同工艺参数条件下支承辊辊套和辊芯之间过盈配合面的应力及微动滑移分布,并分析了辊套厚度、配合面摩擦系数、过盈量、轧制力、弯辊力等参数对过盈配合面应力分布及微动滑移量的影响规律。结果表明:过盈配合面上周向应力最大,径向应力次之,且二者均在轧辊压扁区达到最大;离支承辊长度方向对称面越远,过盈配合面上的微动滑移量越大,且压扁区边部的周向滑移量最大,压扁区中部的轴向滑移量最大;支承辊外径不变时,辊套厚度与过盈配合面等效应力成正比,与微动滑移量成反比;摩擦系数对等效应力影响很小,但与微动滑移量成反比;当过盈量增大时,配合面上的接触应力和应变都增大,微动滑移量先增加后趋于稳定;轧制力增大导致过盈配合面微动滑移量和轧辊压扁区等效应力增大,但弯辊力对等效应力及微动滑移的影响均较小。

Distribution and influencing factors of stress and fretting slip on the interference fit surface of composite back-up roll for cold rolling

Three dimensional model of the composite back-up roll for cold rolling was built and the process of strip rolling was simulated based on ABAQUS software, then the distribution characteristics of stress and fretting slip on the interference fit surface between the roll sleeve and mandrel at different technological parameters were obtained. In addition, influences of such parameters as thickness of the roll sleeve, friction coefficient, interference magnitude, rolling force and bending force on the stress distribution and fretting slip were analyzed. The results show that the circumferential stress is the largest one on the interference fit surface, followed by the radial stress, and both are maximized in the flattened zone of the roller. The farther away from longitudinal symmetry surface of the back-up roll, the greater the fretting slip on the interference fit surface is. Circumferential relative slip value gets its maximum on the edge of flattened zone and axial relative slip value reaches its peak in the middle of flattened zone. When the outer diameter of the back-up roll is constant, roll sleeve thickness is directly proportional to the equivalent stress of the fitting surface while inversely proportional to the fretting slip amount. Friction coefficient has little impact on the equivalent stress but is in inverse proportion to the fretting slip amount. With the increase of interference magnitude, the contact stress and strain become larger, and the fretting slip increases at first then tends to be stable. The fretting slip on the fitting surface and equivalent stress in the flattened zone of the roller increase with the rise of rolling force, but bending force has little effect on both equivalent stress and fretting slip.