论文部分内容阅读
电弧炉用的电极是由带有螺齿的两头为园锥形的接头连接成电极柱。由于接头的直径比所连接的电极尺寸小,因此,接头必须具有较高的强度以及横向较高、纵较低的热膨胀系数。连接体在热膨胀系数上的差异引起严重的热应力使接头孔变形,甚至使连接失效。失效可以图1(a)所示的各种形式出现。所有这些失效形式可能是由热应力引起的,虽然机械力也能引起失效,但通常,机械力所引起的失效在较低温度比高温更易于出现。几年前,已提出了图1(b)所示模型的有限元分析程序。这个模型具有当今电弧炉工业中最普遍的连接装配工序的特征,接头装入电极的上端接头孔直到全螺纹啮合。电极联结是从电极接头孔的下端不断增进,然后拧紧。
Electric arc furnace electrode is composed of two ends with a cone-shaped conical connector into the electrode column. Because the diameter of the connector is smaller than the size of the connected electrode, the connector must have a higher strength and a higher transverse and lower thermal expansion coefficient. The difference in thermal expansion coefficient of the connector causes severe thermal stress to deform the connector hole and even invalidate the connection. Failure can occur in the various forms shown in Figure 1 (a). All of these forms of failure can be caused by thermal stresses, which, though mechanical forces can cause failures, are usually more prone to failure at lower temperatures than at higher temperatures. Several years ago, the finite element analysis program for the model shown in Figure 1 (b) has been proposed. This model features the most common connection assembly procedures in the electric arc furnace industry today, with the connector fitting into the upper terminal hole of the electrode until full thread engagement. The electrode connection is continuously increased from the lower end of the electrode connector hole, and then tightened.