Johan Sverdrup project

Statoils specifications for super duplex bolting material refers to VN605. In addition there is a high strength version of super duplex bolting donated VN602/604, but rarely to be used in this project.

VN605 requires solution annealed properties similar to MDS D60. VN602/604 refer to strain hardened bolting material with mechanical properties similar to B7/L7 and similar to MDS D59.

To ensure compliance with these requirements, the steel mill as well as the bolt manufactuer must be approved in accordance with Norsok M-650 version 4. The bolt manufactuerer must hold an approval in accordance with Norsok M-630 MDS D59/MDS D60 and Statoil must in addition approve the Qualification Test Record prior to appearance on Statoils list over approved manufacturers.

To ensure availability of super duplex bolting material to the Johan Sverdrup project, Würth Industri Norge AS have been involved in two parallel approval processes with Stainless Steel Fasteners Ltd in England and Industria Meccanica Lombarda srl in Italy.

Current approval status SSF:

  • Rolled Super Duplex Stud bolts in range ½” – 3 ½“, According to Norsok M-630, MDS D60
  • Machined Hexagon Heavy Nuts in range ½” – 3 ½“, According to Norsok M-630, MDS D60
  • Machined Hexagon Head Bolts in range ½” – 3 ½“, According to Norsok M-630, MDS D60
  • Die forged Hexagon Heavy Nuts in range 8 – 45 mm thread, According to Norsok M-630, MDS D60
  • Die forged Hexagon Head Bolts in range 8 – 45 mm thread, According to Norsok M-630, MDS D60

Approvals in process and expected finalized during first half of 2016:

  • Strain Hardened Super Duplex Stud bolts in range ½” – 2 ½“, According to Norsok M-630, MDS D59

Current approval status IML:

  • Rolled Super Duplex Stud bolts in range ½” – 3 ½“, According to Norsok M-630, MDS D60
  • Die forged Hexagon Heavy Nuts in range ½” – 3 ½“, According to Norsok M-630, MDS D60
  • Strain Hardened Super Duplex Stud bolts in range ½” – 2 ½“, According to Norsok M-630, MDS D59

For futher information and access to QTR front pages, please do not hesitate to contact Your sales representative.

Best regards,

Morten Frydendall
M. Sc. Materials Science