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Ramnäs Bruk

Reliable Moorings, Anchor Chains and Accessories

PO Box 14,
SE-730 60 Ramnäs,

Ramnäs Bruk develops, manufactures and markets anchor chains, RAMFOR connectors and accessories for qualified mooring systems, mainly to the offshore industry. We manufacture high quality offshore mooring chains, stud or studless, in heavy duty material in long continuous lengths including chafe chains, and is approved as a manufacturer by all major classification societies for both offshore grades and ship’s grades.Ramnäs Bruk is the first choice of the customers, who give priority to quality in all stages.


Ramnäs Bruk products are built with quality and based on a truly long history of chain manufacturing. The product reliability achieved in every delivery is a result of thorough craftsmanship in combination with experience collected. We have developed manufacturing processes, control and inspection routines that withstand any comparison.

We combine a high quality product, manufacture of anchor chains in continuous lengths. Ramnäs Bruk’s anchor chain cable will be found in use worldwide on oilrigs, offshore loading terminals, FPSO’s and onboard ships.

The preferred production range is 70mm to 165mm diameter in all grades, except offshore grade R4, which includes max 157mm diameter. Ramnäs Bruk chain grades include grade 2, grade 3, ORQ, ORQ+10%, ORQ+20%, NVR3/R3/RQ3/QR3, NVR3S/R3S/RQ3S/QR3S, NVR4/R4/RQ4/QR4 and Grade 4+.


Ramnäs Bruk’s stud anchor chain is fitted with drop forged studs. The asymmetrical design of the stud gives equal stud footprints and contributes to a symmetric stress-distribution in the link. This design combined with Ramnäs Bruk’s stud expansion, performed after proof loading is the standard method in Ramnäs Bruk production process since 1991. The benefit is reduced percentage of loose studs in stud link mooring chain. The percentage of loose studs has been cut from an average of 30% to 70% to 0.29%. The asymmetrical stud design and the procedures for stud expansion are approved by ABS, DNV and LRS.


Ramnäs Bruk studless link can deliver the same performance as a stud link in terms of static strength while offering a saving of some 9% in weight. For deepwater applications, there is a potential reduction in weight, and consequent cost saving. Alternatively, the weight can be kept constant and fatigue strength correspondingly increased by opting for a larger diameter chain. This option also gives a greater margin of safety against the incidence of corrosion.


Connectors type RAMFOR has the same outside shape as a traditional Kenter joining shackle, but with improved fatigue properties. The difference is the design of the interior. The RAMFOR and RAMFOR Slim designs have a locking head of a different design than that of the Kenter joining shackles. This locking head has been designed to provide a larger load-carrying area, which in turn gives a better stress distribution. RAMFOR and RAMFOR Slim type connectors have the same outside shape as the Kenter joining shackle and the RAMFOR Slim has a reduced thickness equal to the Baldt type connector.

RAMFOR and RAMFOR Slim are dismantled/assembled in a similar way as the Kenter joining shackle, but with greater ease.


Svenskt Rekonstruktionskapital AB, 60% and AB Arvid Svensson, 40%.

Svenskt Rekonstruktionskapital AB is owned by: Swedish Industrial Development Fund 38% (equity 460 MUSD). Skandia Life Insurance 38% (assets under management 29,450 MUSD). The Foundation for Baltic and East European Studies 19% (equity 400 MUSD). Carl Bennet AB 5% (equity 156 MUSD).

AB Arvid Svensson was founded in 1883. Owners today: Fredrik Svensson and Rikard Svensson, 4th generation Svensson. Group turnover: 67 MUSD Reported group equity: 31 MUSD. Adjusted group equity: 67 MUSD.


  • Statoil, Kristin, 134mm SL*, NVR4
  • Bluewater, Sable Field, 124mm SL, R3S
  • McDermott, Frontrunner, 5¾in SL, RQ4
  • McDermott, Medusa SPAR, 5¾in SL, RQ4
  • APL, Bayu Undan, 156mm SL, NVR4
  • Saipem, Cakerawala, 95mm SL, RQ3 RQ4
  • Statoil, Åsgard, 142mm SL, NVR4
  • SBM, BP Schiehallion, 6¼in SL, R3S
  • Sofec, Shell Todd Maui B, 4¾in 6in, ORQ
  • Norsk Hydro, Troll, 152mm, NVK4-Rig
  • Shell, Auger TLP, 53/16in, NVK4-Rig
  • APL, Energy Bridge, 134mm SL, RQ4

* = studless

Girassol FPSO, Luanda, Angola

Girassol is one of the four major production hubs of Block 17, which is operated by Total and its consortium partners.

Otis Field Development, Gulf of Mexico

Otis is a deepwater discovery located in Mississippi Canyon block 79 in the Gulf of Mexico. The field lies in a water depth of approximately 3,800ft.

Kristin Deepwater Project

The Kristin field is located in the south-west part of the Halten Bank in the Norwegian Sea.

Protect Your Oil Rig with Ramnäs Bruk Offshore Anchor Chains

Ramnäs Bruk, a leading manufacturer of anchor chains for the offshore industry, has released a white paper on its Swedish offshore anchor chain, which is able to withstand the immense power of Mother Nature. To the best of our knowledge, not a single oil rig secured with a Ramnäs chain

Ramnas to Broaden Products and Services

The owners of Ramnas Bruk has recently acquired an engineering company registered in Singapore, which will offer products and services related to the mooring of rigs and floaters for the offshore oil and gas industry. The company, named Ramnas Offshore, has a subsidiary engineering and procuremen

Ramnäs Bruk

PO Box 14

SE-730 60 Ramnäs



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