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This small, but highly engineered Expansion Joint for a sand removal cyclone skid on an oil platform in Norway. This unit is externally pressurised, tested at 45 barG and made from Inconel 625 and Duplex. Read about the client benefits in the case story.

This small, but very special Expansion Joint is engineered and delivered by Norborn for an oil Platform in Norway.

Client issue

The oil platform had two pipes going into one pipe in their sand removal cyclone. This constellation of the pipes resulted high pressure and high pressure thrust force on this section of the pipeline. Normally installation of an Expansion Joint may not be the preferred solution at first, however an Expansion Joint ended up being the exact solution the client preferred.

Why installation of an expansion joint?

The preferred component to absorb both the movements high pressure and high pressure thrust force generated in the cyclone of the oil platform, is often a pipe loop or and expansion joint. A pipe loop expansion joint is space-requiring to be as flexible as an Expansion Joint. Further a correct designed expansion joint can both absorb large movements and operate under critical parameters when carefully designed for it. In this way the Expansion Joint actually can ensure smooth and safe operation. After deep analysis, advanced calculations, Inventor models made by Belman’s skilled and experienced engineers, it turned our that an Expansion Joint was the best component for this pipe section.

Added value to the oil platform

Belman in close cooperation with the oil platform and its cooperative partners designed a highly engineered Expansion Joint, which were a combination of both an Inline Pressure Balanced Expansion Joint and an Externally Pressurized Expansion Joint bringing the features and benefits of both types. This remarkable solution was designed according to ASME and NORSOK and made from 100% Duplex except the bellows, which were being made from Inconel 625 to ensure the highest possible flexibility and at the same time resistance to corrosion. As the media is sand sludge containing sea water, high requirements were put on the materials and on the solution and its weldings to eliminate options for the media to pack up and make the expansion joint corrode earlier than expected. With this Expansion Joint solution all challenges were solved in one component.

Client benefits

  • Safe and smooth operation
  • The best solution of all options
  • Absorption of movements resulted by high pressure and high pressure thrust forces
  • An innovative and top engineered component that ensure no risk of unplanned shutdown

Design parameters of the highly engineered Expansion Joint

This highly engineered Expansion Joint has the following design parameters:
Dimension: DN 150 • Design temperature: 95°C • Design pressure: 30 barG • AX: +/-10 mm • Bellows: Inconel 625 • All other components: Duplex 2205 • Design code: ASME and NORSOK

This small, but very special Expansion Joint is engineered and delivered by Norborn for an oil Platform in Norway.