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一、简介汽轮机及锅炉的螺栓属高温紧固件,对机组长期安全运行起着举足轻重的作用。汽轮机螺栓用钢除了应有良好的室温综合机械性能外,还必须具备高的热强性,高温下抗应力松驰能力,持久强度及时效稳定性等等。螺栓断裂是酿成电厂严重事故的主要原因之一。为消除隐患,故各电厂均把螺栓作为金属监督的重点对象。另外,螺栓紧固件的工作寿命直接影响机组大修期的长短。在目前我国电力行业提出将机组大修期从一年半延长至三年的情况下,螺栓的选材更具有特殊重要的意义。
Brief introduction Turbine and boiler bolts are high temperature fasteners, the unit long-term safe operation plays a decisive role. In addition to the steam turbine bolt steel should have good comprehensive mechanical properties at room temperature, but also must have high thermal strength, high temperature stress relaxation ability, long-lasting strength and aging stability and so on. Bolt breakage is one of the major causes of serious accidents in power plants. In order to eliminate hidden dangers, all power plants regard bolts as the key targets of metal supervision. In addition, the working life of bolt fasteners directly affect the length of unit overhaul period. At present, China’s power industry proposed to overhaul the unit from a year and a half to three years under the circumstances, the selection of bolts more of special importance.