minimum facilities offshore platform

Gulf of Suez Minimum Facilities Platform Installation

2H planned and managed the challenging jack-up installation of a minimum facilities platform offshore Egypt whose design was finalized before installation was considered.

LOCATION  Gulf of Suez, Offshore Egypt          WATER DEPTH   65m

Background

Advanced Energy Systems (ADES) was responsible for installing a pile-supported minimum facilities platform and drilling wells in the Gulf of Suez, offshore Egypt in 65m water depth. ADES proposed installing the 3-part platform weighing 220 metric tonnes using the same drilling rig planned to carry out the drilling operations, to eliminate the need for additional vessels and significantly reduce installation costs for the operator.

With considerable experience in minimum facilities platforms, 2H Offshore was contracted to carry out installation engineering activities as well as supervise the first offshore installation.

Installation Engineering

The platform design was finalised before full consideration was given for installation, so the project was a challenge from the outset. Our engineering team started by reviewing all the design documents and preparing a preliminary project plan which included several engineering tasks and an initial installation plan. This allowed us to highlight areas of risk and potential mitigations. We also met with the drilling rig team and visited the rig early in the project to ensure both the engineering team and the offshore team were aligned. The preliminary plan was discussed with the offshore team and the suggested mitigations were refined until the offshore drilling crew approved of the installation operation.

Once the plan was agreed, the 2H team was able to carry out the engineering tasks, which included designing and sourcing a lifting hook, structure lifting analyses, rigging specifications, vessel stability analyses, Texas deck design and a detailed installation procedure. Careful consideration was required at every step as a result of tight tolerances due to the large footprint of the structures, the water depth, the challenging clamping arrangement and the limitation on the diver bottom time.

ADES Minimum Facilities Platform Installation

Platform Installation

Detailed design work for the project started in mid-September 2018 and offshore installation activities commenced in January 2019. The installation started with a campaign to install the subsea template, the first part to be installed over two pre-installed conductors terminated 2m above the seabed. The activities completed for this operation included:

  • Positioning the rig using high position tolerance to achieve the required installation tolerance for the platform and ensure rig reach for the installation envelope
  • Diver-supported installation of the subsea template (28m high, 220 metric tonne structure), achieving a verticality tolerance of <0.2degree
  • Installation of 2H-designed Texas deck
  • Installation of conductors including welding the conductor legs
  • Removal of the Texas deck
  • Diver-supported installation of mid-brace structure including clamps and annulus grouting
  • Installation of topside and clamped riser

This work was successfully and safely completed by ADES in accordance with the 2H installation procedure using equipment designed by 2H.

Challenges

Using a jack-up drilling rig to install a modular platform structure is a relatively uncommon operation and though it can save money by using fewer vessels for the operation, care is needed to ensure the safety of personnel and equipment at all stages. ADES awarded this scope to 2H knowing that we have the extensive installation experience required to accomplish this. This included designing an interface between the platform and the jack-up rig, completing all relevant calculations, engaging with rig personnel to define and oversee the installation, and addressing all associated risks.

Minimum offshore platform

Minimum offshore platform

Summary

This was a challenging project requiring a combined effort between the engineering team and the offshore drilling team to find an optimal, safe solution. 2H’s experience with such installations was instrumental in the successful installation operation, as was the timely delivery of the engineering, the collaborative approach encouraged by 2H, maintaining constant communications between all parties and addressing concerns promptly. The project’s safe completion prompted positive feedback from the ADES team.