二辊矫直机理论VIP专享VIP免费

1 / 6 Theory of Straightening on Two Roll Bar Straighteners 关于二辊棒材矫直机的矫直理论 Bars are straightened on a two roll straightening machine by bending the bar beyond its yield point and at the same time rotating it. The bending is carried out across the horns of the concave roll. 在二辊矫直机上棒材得到矫直，是靠将棒材超过其屈服强度下进行弯曲，并同时将其旋转。在棒材通过凹辊的两个喇叭口处时，对其进行弯曲。 Consider the simplified case of ‘point’ support and application of loads. 按简化的“点”支承和施加载荷考虑。 W = Straightening Load 矫直力 L = Bending Centres 弯曲中心距 ≈ Profile Length 辊身曲线长度 From bending theory按弯曲理论 M = s I y Where 式中:- M = Bending Moment 弯矩 = W .x L 2 2 = W.L / 4 I = 2nd Moment of area of bar being straightened 被矫直棒材面积的第二个弯矩 = p.D4 / 64 where 其中 D = bar diameter.棒材直径 s = Stress induced in section of bar material being considered. 所计算的棒材断面上承受的应力 y = Distance from neutral axis to point of bar being considered. 所计算的棒材上一点到中心轴线的距离 施加在棒材上的弯矩 2 / 6 Stress distribution through bar, smax ≤ bar material yield strength 通过棒材的应力分布，smax ≤ 棒材屈服强度 In order to straighten the bar, sufficient bending moment must be applied to yield the bar some way below the surface. The depth of material subject to yielding must be sufficient for the outer straightened portion of the bar to overcome the unstraightened inner portion. In practice it is found that if the calculated stress induced at the surface of the bar is 1.3 times the material yield strength sy then the required straightening effect is achieved. 为了矫直棒材，必须施加足够的弯矩，以使棒材表面以下在某种程度上得到屈服变形。棒材外层被矫直部分达到材料屈服的深度必须足以用于抑制芯...