Case Study: Heerema’s Selection of RSL for Dimensional Surveys on the Cygnus Project
Client: Hartlepool Heerema
Project Start Date: 03/12/2012
Heerema Fabrication Group (HFG) was chosen by GDF SUEZ E&P UK for the fabrication and commissioning of four topsides for the Cygnus gas field development in the UK Southern North Sea.
Overview:
Heerema Fabrication Group (HFG) was chosen by GDF SUEZ E&P UK for the fabrication and commissioning of four topsides for the Cygnus gas field development in the UK Southern North Sea. The Heerema Fabrication Hartlepool yard undertook this massive project, which included approximately 10,500 tons of fabrication work for various modules and structures. RSL was selected by HFG to provide full Dimensional Control and survey services throughout the project, ensuring precise and accurate fabrication processes.
Project Scope:
The Cygnus project at Heerema's Hartlepool yard included:
Cygnus Alpha: A three-platform bridge-linked complex consisting of a 3,900-ton Process & Utilities (PU) module, two bridges (200 tons and 250 tons), a 250-ton flare, a 1,600-ton Wellhead module, and a 1,500-ton Compression module installed onto the PU module.
Cygnus Bravo: A remote development with a 2,800-ton Wellhead module.
Fabrication Timelines:
Cygnus Alpha Wellhead topsides: December 2012 - March 2014.
Cygnus Alpha PU module, bridges, flare, and Cygnus Bravo Wellhead topsides: June 2013 - April 2015.
Project Execution:
The Cygnus gas field, operated by GDF SUEZ with partners Centrica and Bayerngas, consists of four platforms. The field began producing gas towards the end of 2015, exporting it via the ETS to Bacton.
Dimensional Control and Survey Services by RSL:
RSL's involvement was pivotal from the project tender stage through to completion. Heerema and RSL collaboratively developed a comprehensive Dimensional Control Procedure for each jacket and topside fabrication. The procedure encompassed:
Responsibilities: Clear delineation of tasks and accountability.
Survey Points: Identification of pre and post-survey points.
Calibration Information: Detailed calibration data for equipment.
Tolerances: Defined acceptable measurement tolerances.
Equipment: Specification of the necessary equipment for surveys.
Specialist Measurements: Including flatness surveys.
Standards Compliance: Adherence to relevant project and national standards.
These procedures were approved by Heerema's QC, Construction, and Production teams and were consistently referenced in the Inspection and Test Plan (ITP).
Implementation and Results:
RSL's dimensional control and survey teams provided continuous support throughout the project, working across all shifts to ensure 100% dimensional control coverage. This comprehensive support was crucial for assisting Heerema's project and fabrication teams in maintaining precision and quality throughout the construction process.
Conclusion:
Heerema Fabrication Group's selection of RSL for the Cygnus project exemplifies the importance of precise dimensional control in large-scale fabrication projects. RSL's expertise and thorough procedures ensured that all components were fabricated accurately, contributing to the successful completion and commissioning of the Cygnus gas field development. This collaboration highlights the critical role of dimensional surveys in ensuring project success in the demanding field of offshore fabrication.
