TORSO

Among the potential harmful conditions for turbogroups, torsional vibration is one that is generally overlooked. Because it can lead extremely quickly to dramatic failures, effective protection systems must be able to react within seconds.

TORSO, ENGIE Laborelec’s torsional vibration monitoring system for turbo-groups, tackles this issue effectively and brings peace of mind back to your condition monitoring strategy.

Although the risk of damage due to torsional vibration is generally well assessed at the design stage of a power generation system, later adjustments to the shaft line, or modifications to the external power system, can create the perfect conditions for certain phenomena to develop. These conditions include sub-synchronous resonance or interactions with high voltage DC stations which, in turn, lead to excessive levels of torsional vibration. In most operational environments, this specific type of vibration is not tracked, even though it can abruptly lead to heavy damage such as shaft cracking, blade loss or gearbox failure.

Using specific sensors, easily mountable on toothed wheels or on shaft ends, TORSO protects the shaft line from the effects of harmful torsional vibration. It rapidly detects when this reaches pre-defined thresholds, and trips the unit before severe damage can occur.

Torsional vibration is angular vibration of an object—commonly a shaft along its axis of rotation. It is superposed to the static torsion and occurs at the frequency of the torsional excitation. It may coincide with the shaft’s natural frequencies. Torsional vibration is often a concern in power transmission systems using rotating shafts or couplings where it can cause failures if not controlled.