BP Ampelmann Support Structure

Dales Marine Services Ltd were contracted to fabricate and install a support structure (2 no.) for the Ampelmann Gangway System on board a Platform Supply Vessel. The contract was to have fabrication complete in 4 weeks and 7 days for installation and com.


  • 46te of Steel Box, Circular Hollow and Universal Column Ordered within UK.
  • All supplied in S355J2 Grade Materials.
  • Delivered within 5 days of order.
  • Dales provided the supplier with a cutting list so all steel was supplied cut to length in    order to save time during fabrication.


  • Dales fabricated the 2 structures in 3 weeks using our 24/7 availability. 
  • Holds and Inspections carried out to IT&P with clients QA Team.
  • All welding connections were full penetration with 100% UT Inspection.
  • Fabricated in our workshop in sections and shipped to quayside for assembly. Sections: Base platform and 4 no. leg sections, walkways and stairs. 
  • Fully assembled and tested on quayside
  • Using 2 cranes and a tandem lift we turned the structure for final fit out and trial fit.
  • Scaffolding erected over structures areas to provide safe access to fit gratings.
  • Full structure was completed and ready to install within 4 weeks.


  • Within 7 days we mobilised the foundation steelwork to support the Ampelmann Structure, the Ampelmann Unit, power units and control cabins for gangway system, accommodation modules and FRC Unit. 
  • Reinforcement of underdeck structure was required.
  • Contract lift operation carried out to load 40te Gangway system.
  • Securing of all systems and commissioning.
  • All carried out to DNV specifications and inspections.


  • After 6 months we demobbed vessel and reinstated deck to pre-mob condition. 
  • Storage of support structure remains across from Quayside with specialised transport required.
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