关键词: 冷却塔风机, 叶片, 运行状态, 非接触式, 叶尖计时

Abstract: A new monitoring method of non-contact running status of cooling tower fan blades is proposed based on elaborating the  monitoring technique of running status of cooling tower fan blades and analyzing the reason of fan blade fracture. The method is called blade tip timing monitoring method. And a new monitoring system of non-contact running status of cooling tower fan blades is developed on the basis of the technology of the blade tip timing monitoring method and Single-Chip Microcomputer（SCM）. The system will shut down the fan and output a forecast alarm when the blade breaks down and deforms, so the blade accident will be prevented. It is proved that the monitoring method can greatly improve the reliability of the fan running status monitoring and effectively prevent the accident of the blades, so the monitoring method and system have a wide application value.

Key words: cooling tower fan, blade, running status, non-contact, blade tip timing