1. Experiences with and requirements to jack-ups in Norway
Arne Kvitrud, Petroleum Safety Authority
Presentation at the
13th International Conference: The Jack Up Platform –
City University London September 2011

2. Content Jack-up accident statistics
Jack-up accidents and incidents in Norway
Norwegian regulations
Acknowledgement of Compliance and consent
Summary

3. Jack-ups accident statistics
World:
: 35x ”losses and severe accidents” (Jack et al, 2007)
: about 350 jack-ups in service world wide
Annual frequency = 35 / (350*8)  1 / 80 (125*10-4)
Norway:
: 2x ”losses and severe accidents”
about 7 jack-ups in Norway
Annual frequency = 2 / (7*22)  1 / 77 (127*10-4)
Jack-ups have an extremely high accident rate!
Norwegian statistics in line with rest of the world.
 PSA have for several years given jack-ups a more detailed follow than other mobile units.

4. West Gamma - 1990 Towing in bad weather. Loss of towing line.
Helideck destroyed by a wave.
Life boats torn loose.
Man holes and ventilation channel damaged by life boat.
Water entered the hull.
49 persons jumped into the sea  rescued.
Platform sank.

5. Rigmar 301 - 2001 One generator out of use. Smoke and noise.
The main reason for the damage was the high descending speed (1.5 feet per minute), combined with the attempt to stop the jacking process by pushing the stop button and the emergency stop button.
All the electrical motors were burnt and all the brakes got damage beyond repair.
No injuries on personnel.

6. Mærsk Innovator and Mærsk Inspirer
26 cracks in "span breakers“ of Mærsk Innovator (built 2003)
24 cracks on Mærsk Inspirer (built 2004).
The cracks are of varying sizes and the largest 400mm long.
The cracks are in air, and the main cause is cross flow vortex induces vibrations, increased by parametric excitation and vibrations from machinery.

7. Scour at West Omicron - 1995 and Kolskaya - 1990
West Omicron: scour causing up to 4.3 m settlements.
Kolskaya: The legs moved towards a soft clay.

8. Collisions Low energy collisions on jack-ups:
Mærsk Guardian in 1998, 1999 and 2000.
West Epsilon in 2000 and 2008.
in Norway:
Four collisions with energy > 14 MJ.
Largest energy = 70 MJ in 2009.

9. PSA requirements Management regulation Activity regulations
Technical requirements:
Norwegian Maritime Directorate technical regulations
DNV-standards general
DNV-OS-C104 for site specific assessments
ISO with a regional Norwegian annex

10. Petroleum activities with jack-ups in Norway – required permits
AOC – Acknowledgement of Compliance
Issued to Rig owner/rig contractor/AOC applicant
Issued by PSA
using the Maritime and Health Authorities
Consent
Issued to Operator
Issued by PSA
in cooperation with the Polution and Health Authorities
Discharge Permit
Issued to Operator
Issued by the Polution Authorities

11. Acknowledgement of Compliance
Documentation:
Valid maritime certificates.
Steel qualities.
Safety factors - weight.
Fatigue lives.
Results from vortex induced cross flow vibrations.
The collision capacity.
Inclination test results.
Cracks or damage history
The risk analysis covering collision, structural and foundation failures.
Training and qualifications of personnel to do jacking operations.
For platforms being more than 19 years we have additional questions, as updated fatigue analysis
+ Audits at design office + meetings

12. Documentation at application for consent for jack-ups
Main results from the geotechnical investigations.
Utilization factors from the site-specific analysis.
Results from the verification of structural and geotechnical analysis.
Results from the site-specific ship collision analysis.
Air gap.
Scour prevention.
+ Audits + meetings

13. Summary Jack-ups have an extremely high accident rate - also in Norway
Norwegian accidents and incidents
Towing
Jacking system
VIV fatigue
Collisions
Scour
Regulations and standards
Acknowledgement of Compliance
Consent for drilling or use as flotel