棒材高精度二辊矫直质量控制策略研究

高精度矫直辊辊型设计及工艺参数控制是二辊矫直机的核心技术。为了满足高精度棒材矫直要求，在辊型设计过程中依据矫直辊磨损状态、弹塑性理论、塑性变形硬化系数求解模型及中性层偏移理论，提出“凹三凸二”分段辊型的矫直辊组合形式及辊型设计方法。在此基础上，根据棒材与矫直辊的局部线接触状态，建立棒材二辊矫直倾角及辊缝估算模型，进而探讨二辊矫直工艺参数（倾角、辊缝、矫直速度和导板间距）的变化规律和控制策略，并给出具体设计实例和有限元模拟分析。从矫直力、塑性变形深度、直线度及残余应力等角度，证明该辊型设计方法和工艺控制策略的有效性，且现场试验矫后的棒材直线度小于1 mm/m，完全满足棒材高精度矫直标准。

Study on Control Strategies of Two-roll Straightening for Bar High Precision Straightening

High precision straightening roll design and process parameters control are the core technology of the two-roll straightener. In order to meet the requirements of bar high precision straightening, the design method of “three-stage concave roll and two-stage convex roll” is proposed based on wear state of straightening roll, elastic-plastic theory, hardening coefficient model of the plastic deformation and stress neutral layer offset theory. On these basis, according to the local contact state of bar and the straightening roll, the models of the roll angles and roll gap between bar and straightening roll are established, and the change rules and control strategies of two-roll straightening process parameters (roll angles, roll gap, straightening speed and plates spacing) are studied, and the specific example and finite element simulation analysis are put forward to verify the control strategies. From the straightening force, plastic deformation depth, straightness and residual stress, it is proved that the effectiveness of roll shape design method and process control strategies, the straightness of straightened bars is less than 1 mm/m in the field experiment, and the straightness fully meets the standard of high precision straightening.