U-001 Subsea production systems (2021)

This NORSOK standard is based on the NS-EN ISO 13628 Petroleum and natural gas industries – Design and operation of subsea production systems series of standards. It includes specific requirements and recommendations that are not covered by NS-EN ISO 13628 series or API 17 series of standards.

This standard replaces U-001 Rev. 4, October 2015.

This edition includes the following significant changes with respect to the previous edition:

• structure of the document has been rearranged in order to find the information more easily and for being self-contained;
• new clause for system engineering;
• new clause for system interfaces;
• new clause for subsea production control system;
• updated annex for template in-place design loads and marine riser drilling load;
• update annex for structural design, materials, fabrication, and testing of subsea wellhead, tree equipment and completion/workover riser systems;
• new annex for bolted flange connections;
• new annex for materials and fabrication requirements for subsea production systems; — new annex on geotechnical aspects;
• new annex on flow induced vibrations;
• new annex on system design documents;
• new annex on interface management;
• new annex on fishing gear classes;
• new annex on wellhead configuration and loads; and
• new annex on recommendations for future subsea production control systems.

Additional documents for downloading 

• Annex B references a report based on a Joint Industry Project, see DNV GL 2014-0783 NORSOK U-001 Well System loads.
• Typical template loads are given in Annex A, Table A.1. Template loads for site specific conditions can be calculated by spreadsheet which is available at this link, NORSOK U-001:2021 - Input data Annex A Table A.1. Excel spread sheet Revision 1F (2020-10-30)
• Annex A references a technical report covering Marine drilling riser loads on subsea wells on the Norwegian continental shelf using semisubmersible drilling rigs: 4Subsea Report 26583U-1762362461-2 Revision 2.0 (2020-11-03) 1685 NORSOK annex A revision
• If there is a need for reduction of wellhead marine drilling riser loads for project specific conditions, the attached 4Subsea Technical Note regarding reducing wellhead loads from marine drilling operations can be used for guidance, 4Subsea Technical Note: Reducing wellhead loads from marine drilling operations
• The rationale for updated NORSOK U-001 drilling loads is outlined in the following OMAE paper:  “OMAE 2022- 81380 Rationale for NORSOK U-001 5th Edition Revision of Static and Cyclic Subsea Wellhead Loads”. This paper has been accepted for publication on OMAE2022 and will be available June 2022 thru https://asmedigitalcollection.asme.org/OMAE.