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Swedish industry last delivered a new submarine in 1997. The shipyard in Malmö that delivered Gotland-class submarines closed. A cloud long hung over the Kockums shipbuilders who designed and built those subs. But in 2014 the tension-filled ownership of Germany's ThyssenKrupp Marine Systems with the transfer to Saab, the Swedish firm known for fast planes and solid cars.

Saab announced in April 2014 that it signed a non-binding Memorandum of Understanding to swallow up the shipyard from ThyssenKrupp Marine Systems AB (TKMS AB, formerly Kockums). Saab completed the acquisition for 340 million kronor ($50.4 million) of ThyssenKrupp Marine Systems (TKMS) from German vendor ThyssenKrupp in July 2014. TKMS was since re-named Saab Kockums. The amount falls a long way shy of the billion-kronor deal previously anticipated. Swedish newspaper Dagens Industri speculated on Friday that it would cost in the region of 500 million kronor. Saab Kockums and the Swedish Navy resurrected the A26 submarine project. Retaining the rights to the A26 was a major element in the government's decision to restore Kockums to Swedish ownership, and in 2015 the Defense Ministry committed to buying two of the subs.

Kockums was part of ThyssenKrupp Marine Systems. Since 1986 Kockums has concentrated its activities within the naval sector. In 1998 Kockums and Karlskronavarvet merged into one company as a part of the Celsius Group. Kockums is a full subsidiary of the renown German shipyard Howaldtswerke-Deutsche Werft AG, thus belonging to the HDW Group which has shipyard locations in Germany, Sweden and Greece. The group's headquarters are in Kiel, Germany. The excellent position held by the HDW Group is largely the result of success in naval shipbuilding. The merger of the shipyards has further strengthened their leading position among international submarine builders.

Kockums stands for leading-edge, world-class naval technology - above and below the surface. Kockums designs, builds and maintains submarines and naval surface vessels that incorporate the most advanced stealth technology. Other successful products include the Stirling Air Independent Propulsion (AIP) system, the Kockums Submarine Rescue System and mine clearence systems. Operations are based in Sweden in Malmö, in Muskö and in Karlskrona.

The recently-nationalized Swedish military company Saab suffered yet another setback in June 2016 in its attempts to sell submarines abroad. Poland, one of the countries Saab had pinned its hopes upon, initiated closer cooperation with the German Navy. Germany is one of Saab's top competitors in the sale of submarines.

Saab, which two years earlier took over major submarine plants in Karlskrona and Malmö, was commissioned to produce two A26 submarines for the Swedish navy. The government's investment rested on hopes for a close cooperation with other countries in order to share to costs. However, finding a suitable partner proved more difficult than expected. The first to decline was Australia, which after short negotiations made it clear that Saab would not be involved in its submarine procurement program.

In April 2016, Sweden's neighbor Norway offered with a surprising answer: as submarines are a key component of the country's security policy, Oslo only envisages buying subs from another NATO country. In practice, this has eliminated Saab from the race, limiting the choice to either the German manufacturer ThyssenKrupp or the French sub-maker DCNS. Since then, Saab's hopes have mainly revolved around the Netherlands and Poland. In both cases, the Swedes started collaborating with local shipbuilders to strengthen their position.


The late 1600s were troubled times in the Baltic. The Swedish king Karl XI realised that he needed a naval base in the south of Sweden to defend the recently conquered provinces of Skåne, Blekinge and Halland. Therefore Karlskrona was founded in 1679 as a naval base and shipyard. Karlskronavarvet soon became the leading Swedish naval shipyard, a position it still holds today.

CARLSCRONA or KARLS- KRONA ("Charles' Crown"), Sweden, is a seaport at the southern extremity of the peninsula, on the Baltic, capital of the Ian or province of Blekinee or Carlscrona, 55 miles east by north of Christiansand. It stands on several rocky islets connected with one another and with the mainland by bridges, had broad, clean but somewhat steep streets, with houses mostly built of wood. The harbor is safe and spacious and the entrance is protected by forts. It was founded by Charles XII in 1680. As the chief Swedish naval station the town largely depends on the trade thereby occasioned, but it has also a considerable export trade in timber, tar, potash, fish, etc. Karls- krona was built on several islands, the largest of which is Trosso, connected by floating and other bridges, the one communicating with the main-land being of stone. The streets are very broad and regular; the dwelling-houses are large, and there are many squares, and a shaded garden or park, called Hogland, crowded every afternoon. Along the quays were boats laden with vegetables and fruits from the main-land, and in the early morning with fish. One is soon reminded of the military importance of the town from its geographical position: barracks, fortifications, dismantled inen-of-war, piles of cannon-balls, etc., give a warlike appearance to the place. Numerous islands protect the approaches to the harbor, which are strongly fortified.

Over the centuries some 450 ships have left the slipways. The materials have changed from oak and canvas to armoured steel, carbon fibre reinforced plastic and electronics, but the craftsmanship, inherited from generation to generation of shipbuilders, still remains first-class.

Karlskronavarvet is one of Sweden's oldest industrial sites still in full use. At the shipyard you meet many fascinating mixtures of state-of-the-art shipbuilding technology and history. For instance, the original dry docks are still used, as functional today as they were almost 300 years ago. The mast crane, built in 1803, stands as a beautiful monument beside the docks. The need for the crane is long gone but it is still fully operational.


The other Kockums unit is located some 200 km south-west of Karlskrona, in the city of Malmö. In 1873 Kockums Mekaniska Verkstad (Kockums Mechanical Industry) delivered its first ship, a 700 tonne steamer named Tage Sylwan. Two years later the Royal Swedish Navy orders the steam barge Torpedo. This is the beginning of a long and successful cooperation with the Navy. In the years that followed Kockums built a wide variety of ships for the Swedish Navy including dreadnoughts, destroyers and torpedo boats.

In 1914 the first submersibles from Kockums - the 252 tonne Svärdfisken and Tumlaren (Swordfish and Porpoise) - were put in commission with the Navy. This rather modest start laid the foundation of what is today one of the world's most successful submarine designers and builders - Kockums. Kockums was also a very successful builder of merchant ships. For instance, in 1940 Kockums delivered the world's first all-welded merchant vessel, the m/t Braconda.

Kockums (through its former subsidiary United Stirling) has been involved in kinematic Stirling engine development since the 1960s. Kockums is focused on the installation of its 75-kW Stirling engine, air-independent propulsion (AIP) system into submarines. The company has also licensed a 25-kW engine to Stirling Energy Systems, Inc. for solar-fueled stationary power generation applications. SOLO Kleinmotoren of Germany has been granted a license to utilize the core Kockums engine technology in a 10-kWe Stirling system.

Kockums has developed two four-cylinder engines based on its V-160 design: the 25-kW 4-95 for stationary power generation and the 75-kW 4-275 for naval applications. The company is divided into two divisions: an advanced submarine unit in Malmö and a surface vessel division in Karlskrona. Kockums is a subsidiary of the Germany-based HDW Group. Kockums began work on Stirling engines in the 1960s and established a daughter company for its Stirling work, United Stirling AB, in the 1970s. United Stirling was then later dissolved back into Kockums in 1988. The company presently has approximately 25 full-time employees devoted to Stirling engines. Kockums also has available the technical resources of 200 engineers. Most of the funding for the company's Stirling research comes from internal sources and government contracts.

Kockums became involved in kinematic Stirling engine development in the late 1960s with a technology license from Philips in Holland. The company was initially focused on the V-160 engine design for three application areas when its Stirling development began: submarines, bus engines, and auxiliary power units (APU). The company has now modified its Stirling engine design and narrowed its focus to submarines and stationary power generation applications.

Kockums has developed two four-cylinder engines: the 25-kW 4-95 for stationary power generation and the 75-kW 4-275 for naval applications. The engines operate at a hot-end temperature of 700-750 ºC. Due to the confined and sealed space of a submarine, helium is the working fluid of choice for sub applications. On the other hand, hydrogen is employed for solar power generation applications in order to achieve higher efficiencies. Kockums has achieved efficiencies (LHV fuel to shaft power) as high as 42% for the hydrogen engine and 39% for the helium engine.

Kockums' key strength lies in the durability of its Stirling engines. This is due to the high standards set by Kockums' military clients. The company has built over 200 engines in total. During testing, its submarine engines have operated for 18,000 hours without maintenance. The company also had a recent milestone when one of the solar Stirling systems installed by Stirling Energy Systems, Inc. (SESI) reached 10,000 hours.

Kockums is known for its development of the Stirling Air Independent Propulsion (AIP) system. The Stirling AIP system generates electricity by burning cryogenic liquid oxygen (LOX) with exhaust gases and conventional fuel (i.e., diesel) in a pressurized combustion chamber. When utilized in a submarine, the Stirling AIP system provides power for propulsion and operation of electronic equipment (e.g., sonar, computers, etc.), permitting extended periods of submersion and extremely quiet operation. The combustion pressure is higher than that of the surrounding seawater, allowing the exhaust products to be filtered and dissolved into the water undetected (i.e., no bubbles) without using a compressor.


Kockums has taken over the naval engineering workshops on the island of Muskö. Conseguently, repair and maintenance resources have expanded in the Stockholm area. This is something the Swedish Navy has long wanted. Maintenance is an important and growing sector for the company. It often involves advanced upgrades and modernization, especially in the case of the Swedish Navy, which is reconfiguring its vessels for service with the rapid reaction force and international operations far from home. All former employees of the naval engineering workshop at Muskö have been offered continued employment under the new owner, a chance they have taken, and the workforce now comprises some 70 employees. The Site Manager at Muskö, as before, is Mr. Per Sundberg. The strategy for Muskö includes plans for other players and Kockums to build up a service and maintenance centre on the site. Efforts will be made to broaden the scope of operations to include commercial activities.

The tender submitted and won by Kockums concerns provision of ship maintenance and engine-repair services by the Muskö naval engineering facility, for an initial period of three years, with an option to extend the contract for a further two years. In terms of commercial real estate, this involves the takeover of two docks and offices, as well as a number of other buildings. "This is a good solution for us, and we are positive to the idea. We now look forward to working together and investing in the future," notes Per Sundberg, who has been appointed Kockums' site manager.

There are also plans to expand operations at the Muskö facility to include commercial vessels. Kockums, in alliance with a network of subcontractors, is determined to transform the Muskö facility into a marine engineering centre. Looking a few years ahead, there are also plans to establish a container and ro-ro port in Nynäshamn, in partnership with Stockholms Hamn (Ports of Stockholm). The idea is that shipping will avoid having to navigate all the way into Stockholm, being able to dock in the outer archipelago instead. The transit time between Nynäshamn and Muskö is not long, and their relative proximity will almost certainly generate a number of repair and maintenance assignments.

The Visby project continues according to plan in Karlskrona shipyard, and four vessels have been handed over to the customer, The Swedish Defence Materiel Administration (FMV). The fifth of series is currently undergoing trials. At Karlskrona, the Swedish Navy Gotland-class submarine, HMS Halland, has undergone extensive modernization. The Landsort project forges ahead and HMS Koster has been out on sea trials. Work on the export order involving two submarines for the Republic of Singapore Navy is also intensive. The Swedish Government has stated continued commitment to the development of a next generation submarine, and given a go-ahead to initiate the design phase.

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Page last modified: 05-07-2016 19:22:38 ZULU