Compression

person Harald Tønnesen and Trude Meland, Norwegian Petroleum Museum
Reservoir pressure declined as the gas was produced, so three compressors driven by gas turbines were installed on TCP2 in 1981. Also intended to serve TP1, these devices were installed between the separators and the dewatering units on the platform.
— Main compressor for Frøy gas (was located on the TCP2 platform). Photo: Jan A. Tjemsland/Norwegian Petroleum Museum
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The compressor models chosen were the Alsthom Atlantique type BCL 607 and Nuovo Pigone units.

The compressor units comprise a suction tank, where even more liquid droplets were removed, a compressor driven by a gas turbine, and a heat exchanger to cool down the gas. After being sucked into the compressor, the gas had its pressure boosted to 153 bar. Compressing a gas increases its temperature, so the flow emerging from the compressor had its temperature reduced in a cooling unit from 95°C to 50°C. The coolant was water.

The operators

Right from the start of production from Frigg, Elf saw that natural pressure in the wells would decline and that compression would be needed to meet the British Gas Corporation’s pressure specifications. The compressor models chosen were the Alsthom Atlantique type BCL 607 and Nuovo Pigone units.

Generator B was the first to begin operation, on 18 August 1981. Dedicated operators were put in charge of the compression facility. Finn Husberg was one of them.

“A team went to Italy and were given a tour [by Technip, which manufactured Pigone turbines],” he recalls. “I got involved a little later than the others, which I rather regretted subsequently. Three large gas compressors and the same kind of turbines which drive a jumbo jet were installed. Each jet engine developed 3 700 horsepower. So we had something with a real kick. When that much horsepower was in motion, the noise was pretty fierce.”

The compressors were installed to boost the pressure of the gas being piped to St Fergus. After having condensate and some water stripped out in the separator, the gas continued to the compressor. A special compressor control room was installed on TCP2, right next to the equipment. The compressors were started, stopped and run from there, and alarms registered. QP’s control room could only monitor the compressors through alarms and observation. The actual compressors were supplemented by a good deal of other equipment required to operate them. They were driven by three large turbines – jet engines. Only two were used, with the third in reserve. In addition came coolant pumps and a fuel gas system which removed gas from Frigg production for the turbines. Dedicated personnel were needed to run this facility. People who had previously been process operators on the drilling platform or TCP2’s process facilities were given training in and responsibility for compression. The operator’s job was to ensure stable operation of the whole compressor facility. Much of the job involved adjusting the pressure, carrying out simple maintenance of valves. and conducting tests of such elements as the fuel gas. But alarms could sound.

“If something in the process suddenly went wrong, such as a pressure alarm which was too high, then everything stopped,” relates Husberg. “You can just imagine the big volumes which were in motion, the huge amount of energy being transferred to the compressors when two 37 000-horsepower jet engines of this kind were in operation. When they shut down in a fraction of a second, the whole platform swung by half a metre to absorb the energy. Huge forces were in play. Exciting, very exciting. But the operating characteristics of the compressors were very good.”

Maintenance

Kompresjon, drift,
The main compressor for Frøy gas was located on the TCP2 platform. Photo: Jan A. Tjemsland/Norwegian Petroleum Museum

The operators were responsible for ensuring that the compression facility operated in a stable way. They also carried out simple maintenance tasks. Major jobs were handled by the maintenance department.

“A facility of this kind was accompanied by a huge amount of additional equipment,?”explains Finn Husberg, who worked as an operator on the compression facility. “The maintenance department was responsible for these components. It handled overhauls, stripped down the turbines for us and got them transported. If the jet engines were due to go to Bergen for an overhaul, personnel from Bjørge Offshore disassembled and prepared them for dispatch.”

General maintenance of the turbines and compression equipment was handled by the field’s permanent electricians, instrument technicians and mechanics.

Published August 14, 2020   •   Updated October 20, 2020
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Location of the Frigg archive

person Torkel Time and Vigdis Bergstad
The Frigg archive is located at the National Archives in Stavanger and consists primarily of two sections - Total E&P Norway's records and the records of the Elf Aquitaine Norge Offshore Union (Eanof).

As a result of mergers, the Total archiveconsists in turn of a number of sections. Many departments and offices have also had separate sets of records. These documents deal not only with Frigg, but also with the company’s ordinary operations. The Eanof archive also comprises several sections – the union’s own correspondence files, materials from the chief safety delegate and the transactions of the working environment committee. Material from Elf Aquitaine Norway is also included, since union representatives sat on the company’s board.

ccr-log-aUnder a deposition agreement with Total E&P Norge AS, the National Archives in Stavanger has undertaken to store the material even though it formally remains the property of the records creator. Legal rules on confidentiality will be observed, but enquiries about access to and use of the archive will be considered by the company until a possible future amendment to the agreement.

beskjedbok-forsideBefore the material was sorted, it filled 160 metres of shelving. Rearrangement has reduced this by 50 per cent. The selection aims to document a cross-section of Frigg activities – not only material relating directly to development and operation of the field but also necessary contextual documentation. Space has accordingly been given to land-based operations and general company history. Furthermore, efforts have been made to concentrate on internal company records not found elsewhere. Little of the information reported to the Norwegian authorities (the Norwegian Petroleum Directorate and the ministries) has been conserved by this project. It will nevertheless become lodged with the National Archives’ records when these government document collections are transferred there.

canonclub-kortThe National Archives has only selected 140 technical drawings produced in connection with the construction and operation of the Frigg field’s installations, a tiny percentage of the total. These include flow diagrams, elevations, deck cross-sections and diagrams of well and piping tracks.

Other sets of records at the National Archives in Stavanger also contain materials dealing with Frigg. The most important are the records of the NPD and the Ministry of Industry’s oil office. The latter embraces material transferred in its time to the NPD and subsequently passed on the National Archives.

Overview of the Total E&P Norge Archive

Total E&P Norge consisted originally of the Total, Fina and Elf Norge companies. Elf Norge was originally called Petropar A/S from 1965, but changed its name in 1967. Elf Norge became part of Elf Aquitaine Norge A/S in 1977 (previously Sociète Nationale Elf Aquitaine – SNEA). The company changed its name to Elf Petroleum A/S in 1992. Total Norge A/S and Fina Exploration Norge SA merged in 2000. Elf Petroleum also became part of this company in 2001. It was known as TotalFinaElf until 2003, when its official name was changed to Total E&P Norge A/S.

The French company Elf discovered Frigg in block 25/1 in 1971, and became responsible for its development and operation. Frigg ranked at the time as the world’s largest offshore gas field. It straddled the UK-Norwegian boundary line, and accordingly became a collaboration between Britain and Norway (40 per cent UK, 60 per cent Norwegian). The platforms were divided between the two sectors. Plans called for the quarters platform (QP) to stand entirely on the UK side of the boundary, but 10 metres of one corner extended into the Norwegian sector. The two countries nevertheless agreed on a practical boundary midway along the bridge between treatment platform 1 (TP1) and treatment and compression platform 2 (TCP2). A sign on this bridge marked the frontier between Britain and Norway. The boundary provided an opportunity for duty-free sales on QP. TP1, TCP2 and QP collectively formed the core Frigg platforms, also known as the Frigg complex. Drilling platform 2 (DP2) and the flare platform (FP) on the Norwegian side plus concrete drilling platform 1 (CDP1) and manifold compression platform 01 (MCP-01) in the UK sector comprised the remaining Frigg installations. The Frigg area also embraced the North-East Frigg (NEF), East Frigg (EF) and Lille-Frigg (LF) satellites.

Records creator: Pa 1362 – Total E&P Norge
Former names: Elf Aquitaine Norge A/S, Elf Norge. Elf Petroleum Norge A/S, Petropar A/S, TotalFinaElf, TotalFinaElf Exploration Norge A/S
Period: 1967-2007
History: period from 1965 (about) to 2007 (about)
Scope: 80 shelf metres
Access restriction: Restricted private archive, access given to former archive owners.

Description of the archive:
The records have a range of provenances because of all the mergers (see history) and because many offices and departments established their own archives (including two offices when the company was called Elf Norge – one for administration in Oslo and the other for technical activities in Stavanger). Elf Aquitaine Norge created the bulk of the archive, but since no sharp division by periods was made at the time of the mergers, it has been difficult to separate out the Elf records. It is very hard to document the original structure of the archive. Various departments and individuals in Elf have delivered material for which they were responsible, but which they did not necessarily create, to the remote archive. The latter has recorded which department supplied the material. This has often provided the basis for structuring the records into series. Other archives were delivered from the relevant department, which has in turn formed the basis for structuring the series. The material is a selection covering 160 shelf metres (unsorted) made in connection with the Frigg industrial heritage project. This choice was made from several thousand shelf-metres in all. Weight was given to documenting the human side of the activity. The technical/production aspects of the business will largely be documented in the NPD archive. Preserving documents found only in the company’s archive has also been a priority. Information reported to the authorities will be found in the relevant government records. The archive documents not only the Frigg field, which was in operation from 1977-99, but also the company’s regular activities. In this way, activities on Frigg are located in a necessary and broader company context. The series, item and folder descriptions are in both Norwegian and English. The records have largely retained their original titles. Their content is largely in Norwegian and English, but includes some documents in French.

Overview of the Eanof Archive

The Elf Aquitaine Norge Offshore Union (Eanof) was established in 1977. It was (and remained in 2007) part of the Norwegian Union of Energy Workers (Safe), previously the Federation of Oil Workers? Trade Unions (OFS) and before that the Union of Operator Employees (OAF).

Records creator: Pa 1415 – Elf Aquitaine Norge Offshore Forening (Eanof)
Period: 1977-2003
Scope: 17.8 shelf metres

Description of the archive:
The records probably have several provenances, because they also contain material from the chief safety delegate (Hovedvernombudet – HVO) and the working environment committee (Arbeidsmiljøutvalg – AMU) in Elf/Total. Eanof officials are likely to have also been represented in the HVO and AMU, or to have received copies of documents within their ambit. Moreover, the achieve includes a number of documents from Elf Aquitaine Norge, including board documents. The union had representatives on the company’s board. As finally organised, the material fills 17.8 shelf metres. The bulk is organised by subject. The correspondence files are organised by file index, and some of the internal memos are arranged in accordance with the National Archives’ own filing system (see the series description).

Overview over David Robert Bayly archive

Bayly started keeping a note book at the end of 1974 initially to assist him in organising his work as the principle structural auditor for the Dunlin A concrete substructure. Initially the note books containing very brief details of events including actions to be taken, facts not to be forgotten, documents received etc. Entries were made as and when necessary and not on a daily basis.

Bayly started keeping a note book at the end of 1974 initially to assist him in organising his work as the principle structural auditor for the Dunlin A concrete substructure. Initially the note books containing very brief details of events including actions to be taken, facts not to be forgotten, documents received etc.  Entries were made as and when necessary and not on a daily basis. Over time a more structured approach was adopted and soon entries were made on a regular basis for most working days.  The day books, usually referred to throughout his working life as his “Black Books” (although for a period they were red!), include records of conversations, notes taken at meetings, lists of things to do, pasted-in notes from his secretary, details of travel arrangements and, since 1993, details of his working arrangements in Norway.  As well as a record of his professional activities the day books also contain a number of entries relating to personnel matters, particularly church activities. The vast majority of the entries in the day books were made at the time the events occurred and no efforts have been made to provide a summary or commentary on the events.  The purpose of the day books was to simply record what factual information not to record events for posterity. The primary reason for recording the minutiae of his working life in a day book has not changed since David first started in 1974.  The purpose, he says, is “to assist me in effectively organising my work and to provide me with a record of actions, conversations and meetings that might be helpful to me in the future”.

Records creator: David Robert Bayly
Born in Catford in South East London. Father Paul W. Bayly, shipping clerk in a firm of oil and seed brokers, mother Alice Violet Bayly. Family life centred on the local Baptist church. Still actively involved in church life. Education: City University London – BSc (Hons) (1962 – 1966), City University London – PhD (1966 – 1969). Married Doreen Janet Cliffe in 1967, 3 children. Working Background: City University London (1969 – 1971 lecturer in the theory of structures), Pell Frischmann Group (1971 – 1994), Crandon Consultants Ltd (1994 -). Involved in the offshore oil and gas industry since 1973. 1977 to 1993 he was responsible for the technical and commercial management of many design projects including topside modules and decks, steel jackets and subsea production facilities in both the northern and southern basins of the North Sea. He also supervised numerous field development and specialist studies including complex stress analyses of pressure vessels and valves on the Frigg Field platforms. In 1993 he came to Stavanger to assist Elf Norge in the preparation of a safety case for the Frigg Field UK platforms as required by the new UK regulations brought in following the Piper Alpha disaster. He has commuted to Norway on a weekly basis. In 1994 he became an independent consultant working mostly for Elf Norge. 1994 – 1996 he was an “integrated contractor” in the Engineering Department of Elf Norge involved in managing risk analyses for the Frigg Field. In 1997 he moved to the HSEQ Management Department of Elf Norge and was responsible for the preparation of Safety Case submissions to the UK Health and Safety Executive and Applications for Consent to the Petroleum Safety Authority Norway. He has been involved in numerous risk analyses and, since 1999, has been part of the team responsible for the decommissioning of the Frigg Field production facilities.

Overview of the Oil Office Archive

Those parts of the archive described here were transferred in their time from the Ministry of Industry to the NPD, and subsequently delivered to the National Archives in Stavanger. The rest of the industry ministry?s archive has been delivered to the National Archive in Oslo. The records primarily comprise documents related to the activities of the oil office, but include materials from before the creation of this body ? probably from the continental shelf committee and the State Petroleum Council.

Records creator:
Ministry of Industry, oil office, Ministry of Industry, oil and mining department, oil office.
Period: 1966-1978

History:
As a result of the large increase in oil-related business, it proved necessary in 1966 to establish a separate oil office in the Ministry of Industry. Government consideration of continental shelf issues had previously rested with the ministry’s mining office. A continental shelf committee appointed by the Crown Prince Regent’s decree of 8 November 1963 supported the ministry in preparing legislation and regulations. The State Petroleum Council was established by royal decree of 9 April 1965 to support the ministry as an advisory body concerning exploration for and exploitation of submarine petroleum deposits on the NCS. This council was the licence-awarding authority when blocks were  handed out in the first offshore licensing round. The industry ministry acquired its own oil and mining department in 1972. The oil office comprises two sections, for technical and geological aspects respectively. The NPD was also established in 1972.

Overview of the NPD Archive

The archive consists of minutes of meetings, memos and correspondence files. These are arranged in such a way that the original archive structure has been retained ? in other words, it accords systematically with the file index used by the NPD. The NPD?s correspondence files are periodised annually.

All correspondence categories can accordingly be found in each annual set. Records begin in 1973 when the NPD became operational, but some documents from 1972 (the DWP project) are included. The correspondence file contains a general section and a section organised alphabetically by approved discovery and field name and by transport systems. An annual set can cover a large number of boxes. Records which lacked a file code have been organised in series E. See also the A-101348 archive, which contains documents from the Ministry of Industry’s oil office in the 1963-75 period. This material was transferred to the National Archives in Stavanger in 2003.

Records creator: Norwegian Petroleum Directorate
Period: 1972-
History: Legal authority and area of jurisdiction: The Storting (parliament) resolved on 14 June 1972 to establish a petroleum directorate in Stavanger to regulate oil and gas discoveries on the Norwegian continental shelf.
Predecessors: Before the NPD was created, government consideration of continental shelf issues was handled by the mining office of the Ministry of Industry. A continental shelf committee appointed by the Crown Prince Regent’s decree of 8 November 1963 supported the ministry in preparing legislation and regulations. The State Petroleum Council was established by royal decree of 9 April 1965 to support the ministry as an advisory body concerning exploration for and exploitation of submarine petroleum deposits on the NCS. This council was the licence-awarding authority for the first offshore licensing round. A big expansion in the volume of business prompted the creation of a separate oil office in the ministry in 1966, and the latter acquired its own oil and mining department in 1972.

Administrative placement: Petroleum and energy issues were transferred in 1978 from the industry ministry to a new Ministry of Petroleum and Energy. Constitutional responsibility for issues relating to safety, the working environment and emergency preparedness on the NCS was transferred in 1979 from the Ministry of Petroleum and Energy to the Ministry of Labour and Local Government. This meant that the NPD subsequently answered to two ministries. The working environment and safety department of the Ministry of Local and Regional Government was formally transferred to the Ministry of Labour and Government Administration on 1 April 2001. Where carbon dioxide issues are concerned, the NPD derives its authority from the Ministry of Finance.

Functions: The NPD was given overall authority to regulate, carry out total safety assessments for and issue regulations governing the petroleum activity. A branch office was established at Harstad in connection with the start of exploration drilling off northern Norway.

Successors: The NPD was divided into two independent regulatory bodies in 2004: the Petroleum Safety Authority Norway, responsible for safety and the working environment, and the NPD in charge of administering petroleum resources.

Published August 2, 2018   •   Updated August 2, 2018
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