Preliminary Learning Points

1
Shell EPW-RTD HSE Early Learning Bulletin
Fountain No 317637 Location Canada
Unconventional Gas AOI1 Date 29 Nov 2008
PLD (HPI) Failed Shackle Rig move contractor
is to skid the rig a distance of 2 meters. The
estimated weight is 250 ton gross for
substructure, derrick, draw works, top drive and
drill pipe. Two bed trucks are hooked to the
substructure as per contractors Safe Operating
Procedures. During the initial pull a rigging
failure occurred and dislodges keeper pin from a
shackle across the lease. No injuries, no
damages to cargo or property.

• Preliminary Learning Points
• 51 Safety factor existed on rigging components
  (clevis, tail-chain and snatchblock)
• SWL of clevis is 17 ton
• Winchline and sling are in double line
  configuration ( 25 ton capacity)
• SWL of Snatchblock is 25 ton
• SWL of tail-chain is 25 ton
• This rigging configuration was as per Mullen SOP
  for double lining.
• Exclusion zone increased for this non-routine
  skid to 10m from point of failure rather than
  from truck perimeter.
• No physical barrier was in place.
• No workers were in the exclusion zone.
• The pin travelled 30m, leaving the exclusion
  zone.
• No weight indicating measurement method for
  actual load put on lifting equipment.

Protective Cage
Safety Chain
Failed Pin
Re-Enactment
This Learning Bulletin provides preliminary
learnings. A detailed investigation is pending.
For internal use only.