What happened: During cellar jetting operation utilizing the main mud pumps, an unknown object becam

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Shell EPW Wells HSE Learning Bulletin
Fountain Report No 123731
Location Pinedale, WY
Incident Date 1/02/2007
What happened During cellar jetting operation
utilizing the main mud pumps, an unknown object
became lodged in the high pressure pump system
causing a spike in pump pressure (5000lbs)
resulting in a pressure fracture between the 4
inch main mud line 2 inch welded outlet. Said
high pressure projected an attached Demco valve
assembly towards the base of drilling floor. An
employee, while monitoring jetting operation
located in rig sub structure, received minimal
blunt force trauma to the right posterior lower
leg from an unknown projectile. EE was assessed
by site HSE Tech and refused further medical
treatment.

• Early Learning Points
• Utilize charge pump to establish circulation.
• Test relief valve (pop-off) with a lower pressure
  penny nail.
• Slowly increase pump strokes watching for
  pressure increase or stall.
• Visually inspect system for obstructions prior to
  operation prior to use.
• Consider effects of weather on equipment (e.g.
  drain lines of water, etc.).
• Incorporate annual inspections on high pressure
  mud systems in preventive maintenance
  system.

Area where welded outlet failed