管线钢DWTT评定影响因素分析

Analysis of Influence Factors on DWTT Evaluation for Pipeline Steel

从冲击能量、锤击速度、对中装置及异常断口4个方面对管线钢落锤撕裂性能的影响因素进行了分析和讨论。结果表明,锤击能量过大不能真实反映材料断裂撕裂性能,锤击速度过大会使材料脆性增加且易发生异常断口,对中装置必须经常检查和调整,异常断口作为有效试样进行评定,测量区内的脆性部分均按照实际剪切面积计算,对于分层断口只将与断面呈一定角度的脆性断裂面计算在内。

In this paper, the impact energy, hammering speed, centering device and abnormal fracture are analyzed and discussed. They are the factors affecting the performance of the DWTr tear pipeline steel. The results show that hammer with excessive energy doesn＇t really reflect material fracture tore performance, the higher hammer speed will make materials brittleness increasing and easy anomalies fracture, and the devices have to be constantly checked and adjusted. The abnormal fracture is evaluated as an effective specimen, and the brittle part in the measurement area is calculated according to the actual shear area. For the delamination fracture, only the brittle fracture surface with a certain angle to the cross section is calculated.