放空塔地脚螺栓断裂原因分析

Cause Analysis of Anchor Bolt Rupture of Blowdown Tower

北方某石化公司焦化装置改造于2003年9月竣工,运行两年后,在对地脚螺栓进行紧固时发生6根地脚螺栓断裂。通过现场取样进行化学成分分析、显微组织分析和金相分析,找到了断裂产生的原因:螺栓材料存在严重的低倍缺陷和显微缺陷,在长期拉应力、交变应力作用下发生屈服破坏,导致断裂。

The reformation of the delayed coking unit at a petrochemical company was completed in Oct. 2003. Two years later, when fastening the anchor bolts of the blowdown tower, six anchor bolts ruptured. By means of chemical composition analysis, microscopic examination and metallographic examination, the rupture causes were found, which were that serious macrostructure and microstructure defects existed in bolt material and the yield rupture happened in the material under the actions of long-term tensile stress and alternate stress and led to rupture.