CAJ | 학술논문

某电厂一台600 MW汽轮发电机组存在严重的振动不稳定隐患,在机组带负荷过程中,5号、6号轴振出现了突发性的17.5 Hz低频振动,幅值分量达170 μm.通过对该机组轴系相对标高变化、振动和油膜压力的测试分析,得出轴系标高不合理是导致机组振动失稳的主要原因之一.介绍了机组振动测试情况和轴系标高测试试验方法,结合标高检测结果,分析了该机组轴系标高随工况的变化规律.测试结果表明,从冷态到热态,4号轴承标高相对5号轴承抬高达1.180 mm.经综合分析,制定并实施了冷态下轴系标高调整方案,5号轴承相对4号轴承抬高0.9 mm,彻底解决了该机组轴系振动不稳定问题.
모전엄일태600 MW기륜발전궤조존재엄중적진동불은정은환,재궤조대부하과정중,5호、6호축진출현료돌발성적17.5 Hz저빈진동,폭치분량체170 μm.통과대해궤조축계상대표고변화、진동화유막압력적측시분석,득출축계표고불합리시도치궤조진동실은적주요원인지일.개소료궤조진동측시정황화축계표고측시시험방법,결합표고검측결과,분석료해궤조축계표고수공황적변화규률.측시결과표명,종랭태도열태,4호축승표고상대5호축승태고체1.180 mm.경종합분석,제정병실시료랭태하축계표고조정방안,5호축승상대4호축승태고0.9 mm,철저해결료해궤조축계진동불은정문제.
There exists a serious hidden trouble capable of causing an unstable vibration in a 600 MW turbo-generator unit of a power plant. During the load carrying period of the unit, a low frequency vibration at 17.5 Hz suddenly occurred to shaft No.5 and 6 with an amplitude component equaling to 170 μm. A measurement and analysis of the change of the relative levation, vibration and oil film pressure of the shafting system of the unit have induced one to conclude that the irrational elevation of the shafting system constitutes one of the main causes leading to an unstable vibration of the unit. The authors described the vibration measurement conditions of the unit and the methods for measuring and testing the shafting elevation. In conjunction with the measurements of the elevation, the law governing the change of the shafting elevation with the perating condition was analyzed. The measurement results indicate that from the cold state to the hot one, bearing No.5 is relatively elevated by 1.180 mm in comparison with bearing No.4. After a comprehensive analysis, a shafting elevation adjustment version was worked out and implemented in the cold state. Bearing No.5 was elevated by 0.9 mm relative to bearing No.4, thereby thoroughly solving the unstable vibration problem of the hafting system.