Fabrication of Offshore Container ENVGL-ST-E271 2017


This standard is free download here.

Topic to guide prepare WPS and Welder performance, welding, inspection and review MTC to comply with Offshore container.

What you should point to review?

  • Scope, see 1.2
  • Relationship with other standard, see 1.3
  • Containers certified to this standard will also comply with EN 12079 part 1 ( Replaced by EN 10855-1 : 2018), part 2 and part 3, here.
  • Definitions see sec. 1.5 must understand to assign properly welding and post welding inspection in sec. 5.

Welding Procedure Specification

  • WPS shall be in accordance with relevant standards of EN ISO 15607, 15609-1, 15614-1, 15614-2 DNVGL-RU-SHIP Pt. 2 Ch. 4 Sec. 5 or other standard AWS D1.1.
  • When impact tests are required and for t >= 12 mm, four sets of impact test shall comply with the requirement in sec. 3.1.1 of this standard.
    • CVN test at weld metal, fusion line, fusion line + 2 mm and fusion line + 5 mm.
    • Section 3.1.1 and table 3-1, if design temperature, temperature shall be considered at lowest temperature in PQR, mean your PQRs shall be reduced -20 deg. C.

If your PQR miss on of above requirement, new PQR or addition testing shall be tested in accordance with relevant standard.

AWS D1.1 allowed to additional a test requirement, if all essential variables are unchanged and met this requirement.

Which standards most preferable to use in offshore container?

  • In the Eurodance are preferable ISO standard rather American standard. Under ISO standard, you will need more WPSs in different connection, weld type, joint type, thickness qualification and also welder qualification in most different thickness, weld type ….
  • If you are selected an AWS D1.1 rule, you may need at least 2 WPSs for fabrication in 6GR as guided in topic of prepare a PQR 6GR.
  • Most companies had applied AWS D1.1 standard, so they are also qualified in different positions and ready fabrication.

Welder performance

  • Welders shall be approved by DNVGL according to a recognized standard such EN 287-1, ISO 9606-1, ISO 9606-2, ASME IX and AWS D1.1.
  • Welders qualified under ASME IX are normal rejected by Owner. So, please get them approval before welding.
  • Welders qualified under AWS D1.1 are widely range of qualification (recommend).

Material and review MTC

  • Before starting or order material, you should read section 3.4 – material certificates.
  • Most material arrived without MTC or do not comply with the requirements, see table 3.6
    • ISO conner fitting and pad-eyes shall be in accordance with EN 10204 type 3.2, read more how to identify a fake MTC 3.2.
    • Impact test for material shall also comply with sec. 3.1 and table 3-1.
    • ISO-conner fitting shall also comply with table 3-2 and table 3-3.
    • Material with Z quality, see 3.1.2.1 for tensions load through thickness with Z25 or better.
  • Welding

To understand this this requirement in section 4.3 for selection of WPS and welder assignment. That is a reason, we recommend to use standard AWS D1.1 for fabrication instead of ISO standard. You also minimize the cost of prepare somethings.

  • Weld connection to pad-eyes shall full penetration weld.
  • Essential and non-redundant primary shall be welded full penetration.
  • Secondary member may be fillet weld.

Inspection

  • To understand of relevant standard to prepare report and NDT for weld joint.
  • NDT shall accordance with table 5-1.
    • Visual: EN ISO 17637
    • MT: EN ISO 17638
    • PT: ISO 3452-1
    • UT: EN ISO 17640
    • RT: EN ISO 17636-1 and EN ISO 17636-2.

Acceptance criteria

  • Visual: EN ISO 5817
  • MT: EN ISO 23278
  • PT: EN ISO 23277
  • UT: EN ISO 11666
  • RT: EN ISO 10675-1
    To check latest edition, here.

Production test, see 5.4

Inspection and certificate, see section 5.6.

Marking, see section 6.

Plating, see section 7.

3 Likes