Testing Services

Acoustic Tests

Acoustic testing involves measuring sound pressure levels and analyzing spectral content to identify the root causes of excessive machinery noise. Sound pressure level testing may also be used to verify Occupational Safety and Health Administration and Environmental Health and Safety compliance.

Emergency Bearing Oil Pump Tests

The emergency bearing oil pump (EBOP) test verifies the operating parameters of the emergency bearing oil system. The test ensures the EBOP provides adequate oil to the turbine-generator bearings during a forced trip that results in a normal lubricating oil system failure or shutdown. We can perform an EBOP test on any turbine-generator with babbitt bearings, regardless of the manufacturer. (Reference document: GE Technical Information Letter (TIL) 914-2)

End Winding Resonance Tests

The end winding resonance test ensures the natural resonances of the generator series loops are not in close proximity to the operating frequencies. By testing for resonant frequencies, you can modify the support structure to avoid possible winding failures. We offer end winding resonance tests for all turbine-generators regardless of manufacturer.

We recommend an end winding resonance test when:

• The unit has been rewound
• Visual inspection such as dusting or greasing indicates relative motion
• The unit has undergone epoxy injection or another end winding repair requiring a rebuild of the series loops
• Acoustic measurements during operation at a frequency of 120 Hz show elevated amplitude at the ends of the machine

Flux Probe Tests

A flux probe detects shorted turns by waveform analysis of the air gap leakage flux. The probe allows you to monitor the health of the generator field winding periodically, and can also diagnose generator field vibration issues. We offer flux probe tests for all turbine-generators regardless of manufacturer.

• Generator Field Winding (2.1MB PDF)

Partial Discharge Tests

Partial discharge analysis is a leading-edge technology used to monitor high-frequency, low-voltage activity within the insulation system of high voltage equipment. The data is used for outage planning and to avoid catastrophic insulation failure. We offer partial discharge analysis for all generators and high-voltage equipment regardless of manufacturer.

Partial discharge can result from:

• Stator bar vibration
• End winding contamination
• Broken conductors
• Insulation damage
• Collector brush sparking
• Naturally occurring voids in stator insulation

• Partial Discharge Analysis (69.7KB PDF)

Stator Water Flow Tests

A stator water flow test is an ultrasonic test of the water flow rates in the stator cooling system of water-cooled generators. It detects cooling circuit blockages in generator windings. We can perform this test during any maintenance outage during which the inner and outer upper half end shields are removed. We perform stator water flow tests on water-cooled generators with homogeneous Teflon® cooling water hoses. (Reference document: GE Technical Information Letter (TIL) 956-3R1)

Vibration Tests

GE provides vibration testing services from simple component resonance testing to modal analysis and operational deflection shapes of complex structures. We also perform vibration survey testing on stationary and rotating equipment for periodic maintenance planning purposes. We perform vibration testing services on any equipment that is subject to vibratory excitation.

• Generator vibration monitoring system (182KB PDF)

Customized Diagnostic Tests

GE offers custom-engineered test and data reduction services to help diagnose unique equipment problems. We service any equipment that requires acquisition of mechanical and/or electrical measurements for inspection, testing or diagnosis.

We analyze the following parameters:

• Displacement
• Vibration
• Temperature
• Pressure
• Strain
• Electrical parameters
• Acoustics

For More Information

• Send email to commsu@ps.ge.com