Emergency oil system failures can result in significant property damage and large loss of revenue. The intent of this Quick Tip is to provide AEGIS Loss Control’s viewpoint on testing critical lubricating and seal oil systems. Original equipment manufacturers (OEM) have various approaches for emergency lubricating and seal oil system testing to ensure reliability and readiness. AEGIS Loss Control’s guidance on testing addresses the common failure modes and may be more or less stringent than the OEM.

AEGIS Loss Control’s experience with emergency oil system failures has been predominantly attributed to the following causes: 

• DC pump lockout
• DC power supply unavailable
• Operator error
• Pressure switch inoperative

A functional test that exercises all elements of the protection system, without compromising the unit, can be achieved by creating a drop in oil pressure at the dedicated pressure switch or sensor.

The following testing to ensure system readiness is considered adequate, regardless of the oil system configuration:

• Steam turbine and generator:
  • Pressure drop test monthly
• Frame and Aero-derivative type combustion turbines (with emergency oil pumps):
  • Pressure drop test quarterly (or)
  • Oil pump motor startup logic permissive test at each start with annual pressure drop test
• Aero-derivative (when equipped with run-down oil tanks)
  • Verify weekly that the isolation valves between oil tank(s) and bearings are open
  • Run-down Tank(s) shall be equipped with calibrated level detectors and low-level alarms

Only qualified and knowledgeable employees should conduct emergency oil system testing. Training/qualification records for approved procedures are essential documentation supporting system readiness and should be maintained per your company’s retention policy.

In addition, AEGIS recommends that a lessons-learned evaluation, including a review of procedures and training, should be conducted after an emergency oil system event.

For further information, you can download our Turbine Lubricating Oil Systems white paper or contact Timothy Irwin, Senior Machinery Professional, Loss Control, via e-mail or phone at 201.508.5739.