INCIDENT:

1
HSE LEARNING

• INCIDENT
• On 16th July Kauther Gas Plant tripped on ESD
  initiated by fire gas detection at the
  condensate holding area. Loss of containment was
  caused by shearing of a pressure gauge instrument
  tubing on the discharge line of the running pump.
  The system pressure at this point is 88 barg,
  causing a jet of liquid/ vapour to hit the roof
  of the holding pit 15m overhead most of the
  liquid fell back into the pit, but some of it
  contaminated the surrounding area. Estimated loss
  of liquid containment is ca 10m3 (estimated 25
  and 75 water). The incident occurred at night,
  with the facility unmanned. After 2 hrs local gas
  detectors picked up the leak, registering gas
  above 100 LFL.
• POTENTIAL C3A/P
• No ignition source was encountered (all Ex-rated
  equipment). A pool or jet fire could have
  resulted in the loss of the condensate pumping
  facility in the pit, with replacement costs of up
  to 1 MMUSD, but would not affect KGP production.
• Potential injury to operator due to fire, or
  slips/trips.
• ROOT CAUSES
• Pump vibration led to fretting of the
  instrument tubing at the compression fitting,
  with eventual stress failure leading to full-bore
  flow to the surrounding environment via the ½
  instrument fitting. The most likely cause of high
  vibration is blockage within the suction strainer
  of the duty pump.
• LEARNINGS
• Vibration
• Suction/ discharge dampers on positive
  displacement pumps to be checked at least
  6-monthly
• Suction strainers should have dP indication
  installed, set to alarm when pump NPSH
  requirements are not met
• Always remove commissioning filters from pump
  suctions
• Consider low flow alarm for pumps
• Detection
• Gas detectors in pits should be located at low
  elevation to aid early detection

Key Learning Design and Maintenance of
(positive displacement) pumps must ensure
adequate safeguards for avoiding blockage and
early detection of vibration.
Process Safety Incident
Use this Alert Discuss in Tool Box Talks and HSE
Meetings ? Distribute to contractors ? Post on
HSE Notice Boards ? Include in site HSE Induction
Contact MSE511 for further information or visit
the HSE Website Alert No 71

August, 2011