OVERVIEW

Turbine supervision is an essential part of the day-to-day running of any power plant. There are many potential faults such as cracked rotors and damaged shafts, which result from vibration and expansion.When this expansion and vibration is apparent in its early stages the problem can usually be resolved without any of the disruption caused when a turbine has to be shut down. By appropriate trending of the various measurement points and the identification of excessive vibration or movement, scheduled equipment stoppages or outages can often be utilised to investigate and resolve the failure mechanism.

It is for this predictive maintenance market that Sensonics produces a wide range of sensors and systems specifically for the power generation industry. With flexible and configurable equipment, we can tailor our supervisory equipment to your needs. In this brochure we aim to give a brief explanation of why turbine supervision is so essential and how Sensonics can provide the right solution to protect your turbine. The diagram on page 5 illustrates a generic configuration of a set of Turbine Supervisory equipment. The steam turbine shown is fairly standard with an HP (high pressure) stage followed by a single LP (low pressure) rotor section; different turbine configurations depending on power rating, may have an intermediate (IP) section in addition to a number of LP’s which finally drive the turbine generator.This type of configuration is illustrated in the adjacent picture. Although the equipment configuration does vary, the measurement techniques remain the same, with each turbine installation generating its own unique set of measurements. Typical measurement techniques include: Absolute vibration of bearing pedestals Shaft vibration relative to bearing Shaft eccentricity Differential expansion or shaft movement Valve position on steam inlet Casing expansion, both inner and outer Speed, including overspeed and zero speed Temperature Structural & foundation vibration monitoring Each of the measurement techniques are used to monitor the turbine during its operating cycle, some measurements may be configured to provide warning alarms as well as automated shutdown, although these systems tend to operate on a voted principle to ensure maximum system integrity.

Atypical Turbine Supervisory Equipment Application