Alexander Kielland platform disaster what really happened? March 30, 1980
This is really odd bit of history, I have no real hard opinion on this accident, however i do believe the Oil Company blackmailed the Norwegian government into rushing forward with continued exploration in North Sea regardless of accident and they would not wait for investigation, they would not wait regardless of safety or lives lost. Drilling continued almost exactly as planned in time frame, with flags and banners waving … big surprise eh.
You can read more regarding these type questions here
By Thomas Mathiesen
Official Story ~
A floating apartment for oil workers in the North Sea collapses, killing 123 people, on this day in 1980.
The Alexander Kielland platform housed 208 men who worked on the nearby Edda oil rig in the Ekofisk field, 235 miles east of Dundee, Scotland. Most of the Phillips Petroleum workers were from Norway, although a few were American and British. The platform, held up by two large pontoons, had bedrooms, kitchens and lounges and provided a place for workers to spend their time when not working. At about 6:30 p.m. on March 30, most of the residents were in the platform’s small theater watching a movie. Although there were gale conditions in the North Sea that evening, no one was expecting that a large wave would collapse and capsize the platform.
The capsizing happened very quickly, within 15 minutes of the collapse, so that many of the workers were unable to make it to the lifeboats. The Royal Air Force of Great Britain and Norwegian military both immediately sent rescue helicopters, but the poor weather made it impossible for them to help. Most of the 123 victims drowned. A subsequent investigation revealed that a previously undetected crack in one of main legs of the platform caused the structure’s collapse. The Alexander Kielland sat in the water for three years before it was salvaged.
Eight years later, a fire and explosion on the Piper Alpha oil rig in the North Sea killed 167 workers.
- Failed structure: Pentagone type semi-submersible rig
- Date: 27 March 1980
- Place: Ekofisk field, North Sea
- Conditions: Bad weather, ~60-75km/hr wind speeds, ~6-8mm wave height
- Failure mode: Fatigue failure followed by brittle fracture in one brace and ductile overload in remaining adjacent braces
- Cause: Fatigue crack growth from a weld defect
- Consequences: Loss of 123 lives and platform
Fig.1. Alexander L Kielland accommodation platform (Reproduced courtesy of the Norwegian Ministry of Justice)
On the evening of 27 March 1980, one of the five columns of the ‘Alexander L Kielland’ accommodation platform anchored in the North Sea, broke off (see Fig. 1). (The five columns were the principal buoyancy elements of the platform). The platform immediately heeled over to an angle of 30-35° and then continued to heel and sink slowly. Twenty minutes after the loss of column D, the platform capsized. Of the seven lifeboats on board, only two were launched successfully albeit with great difficulty in part due to bad weather conditions (one landed upside down in the water). Some inflatable rafts launched themselves due to the listing of the platform. A massive international air and sea rescue operation was undertaken. Of the 212 men on board the platform when it failed, 123 died.
The Alexander L Kielland was a semi-submersible mobile rig of the Pentagone type, a design which had been developed in France. The rig was built between 1973 and 1976 in France for an American operator. Although it was designed as a drilling rig, it was only ever operated as an accommodation platform during its four years in service.
The platform had five columns, of overall height of 35.6m, mounted on 22m diameter pontoons. The columns were positioned at the apexes of a pentagon with braces running between adjacent columns and the deck or hull. Accommodation units and a drilling tower were mounted on the deck.
Causes of Failure
Following the accident, the platform and the separated column D remained afloat. Column D was towed to Stavanger and divers removed all the fracture faces from the capsized platform for investigation (see Fig. 2).
The Commission responsible for the inquiry into the disaster concluded that the structural failure had occurred in the following stages:
- Fatigue crack growth in brace D6 initiating from pre-existing cracks in the fillet welds between a hydrophone support and the brace
- Final, mainly ductile, fracture of brace D6
- Subsequent failure of five remaining braces joining the column to the structure by plastic collapse
Fig.2. Alexander L Kielland accommodation platform (fracture face)
Brace D6 and the hydrophone support were both made from a C-Mn structural steel (equivalent to a Lloyds’ ship steel Grade EH) with a minimum specified yield strength of 355N/mm 2. The brace was 2.6m in diameter with a wall thickness of 26mm. The hydrophone support was 20mm thick with a diameter of 325mm and was set-through the brace. It was attached to the brace by two fillet welds, one on the outside of the brace and the other on the inside. Examination of these fillet welds revealed poor penetration into the hydrophone tube material and an unsatisfactory weld bead shape. Significant cracking was also found which was dated to the time of fabrication by the presence of paint on the fracture surfaces.
Fatigue crack growth in brace D6 originated at the hydrophone support weld and extended, in the latter stages partly by ductile tearing, around approximately 2/3 of the circumference of the brace until final failure took place by brittle fracture.
The chemical compositions of the brace and hydrophone material were within specification, as were the Charpy and in-plane tensile properties. The through-thickness ductility of the hydrophone material (which was not specified) was, however, poor. This, combined with its through-thickness tensile strength being lower than the in-plane strength of the brace material and with sub-standard welding, led to partial cracking of the fillet weld during fabrication.
Although material properties and welding quality played a significant part in this disaster, rig design was also a critical factor. Apart from the stability and buoyancy aspects which were inadequate, the design did not consider attachments to highly stressed braces such as D6 as important. The fatigue performance of the hydrophone attachment and its effect on the fatigue life of the brace were tragically overlooked.
This is a case history taken from Report 632/1998 . For further case histories, Industrial Members may consult the full report.
THE SABOTAGE AGAINST THE OFFSHORE ACCOMODATION PLATFORM ALEXANDER L. KIELLAND.
1. General information in English.
2. General information in Norwegian (norsk tekst).
3. Technical Documentation.
4. FALK Newsletters.
5. What’s new !
6. The Cover Operation …………………………..
7. The Sabotage. …………………………………….
8. Boycott – Bankruptcy – Financial plot
10. List of updates
Mail: FALK International,
Box 799, 7408 Trondheim
E – mail : email@example.com
“KIELLAND -GATE” : WHO KNEW WHAT AND WHEN?
Update July 14th 2009: I NASJONENS TJENESTE
Update July 13th 2009: Norsk Oljehistorie
Update June 22nd 2009: BLOW OUT!
Update June 17th 2009: ALK – Truth!
Update Nov. 5th 2008: Arven etter Hauge del 2.
Update Nov. 4th 2008: Arven etter Jens Chr. Hauge.
Update Nov.1st 2008: Hauge – Tungtvann og “Kielland”.
Update Oct. 23rd 2008 “Jens Chr. Hauges tapte troverdighet” med tillegg.
Update Sept. 5th 2008: KGB og Jens Chr. Hauge:
Update Aug. 8th & Jan. 2nd 2008; Testamente
Update Nov. 29th 2007: Summit – epost med Kreateam
Update Jan. 4th 2007: Obituary
PREVIOUS UPDATES: Go to Section 10: List of updates
one more odd note, this actually happened 27 March 1980, am not sure why it is listed as March 30, 1980 … did it take them that long to notify public of accident?
anyone with more information please feel free to share … thank you