【摘要】 12Cr1MoVG锅炉高温过热器蛇形管弯头,化学成分及力学性能符合国标规定,且使用温度低于580℃但使用不到2a就发生多处破裂,为此,对其开裂行为进行了理化鉴定。结果表明,管子发生的是应力腐蚀破裂,裂纹的形成与弯管应力状态、内表面质量和介质的腐蚀等有直接的关系。裂纹的出现将严重威胁机组的安全运行,所以,在电站锅炉应用中应对具体的环境条件、选材、设计和工艺进行研究,只要措施得当,开裂问题是可以避免的。更多还原

【Abstract】 Boiler’ s serpentine tubes made of 12CrlMoVG steel experienced breakage within a service duration of less than 2 years, though they had qualified chemical composition and mechanical propertiesspecified in relevant national standards and were used below a temperature of 580℃Thus the breakage behavior of the boiler’ s serpentine tubes made of 12Cr1MoVG steel was investigated by means of physical and chemical inspection, aiming at revealing the causes leading to the breakage. Results indicated that stress corrosion cracking (SCC) occurred and the crack formation was related to the stress condition of elbow pipe, internal surface quality and corrosion medium. The cracks generated were greatly harmful to the operation safety and reliability of the boils. Thus it would be imperative to carry out overall studies on environmental conditions, selection of materials, design, and process with respectto the application of the boils at power stations.更多还原