Oil / Angola / Block 0

The context.

Chevron's floating production unit1 (photo) located off the coast of Angola2 is a vessel that has many systems for processing and separating different types of oil, such as a complete oil gas liquefaction system, as well as on-board export facilities. Subject to both the marine environment and the constraints generated by its activities, the integrity of the vessel requires regular maintenance operations, for example in terms of insulation and surface treatment, in order to ensure the safety of people working on board and to maintain production capacity. Miles of pipes allow the circulation of flows, cold or hot. If a pipe freezes, the flow will no longer pass. If a pipe or valve is rusty, production will have to be stopped. If a pipe is poorly insulated while a flow at 150° is circulating, personnel risk serious burns. Finally, rusty superstructures will further reduce the vessel's ability to withstand bad weather conditions.

"One day I received an email containing a very simple freehand sketch, accompanied by about ten lines explaining the project and the needs, from a need for land expressed in a relatively informal way, accompanied by a financial envelope that set a framework, we managed to build, with Prezioso, a tailor-made solution that corresponds to the equipment with which their employees are used to working and which adapts to the specificities of the site of their client Chevron."

Prezioso, subcontractor of the Chevron group

Surface treatment
Angola

Company Profile

Specializing in surface treatment and present in Angola for around thirty years (in different locations: Soyo, Cabinda, Lobito and Luanda), Prezioso mainly works on ISS (surface insulation, scaffolding preparation) but is also developing IMD (site inspection, modification and decommissioning) and also an integrity activity (survey, consulting and management).

The challenge.

One-off and mobile maintenance operations on Chevron assets have been entrusted to Prezioso, a company specializing in surface treatment. They concern anti-corrosion, cold insulation and protection of personnel, whether on the upper part of the ship, the deck and the piping (extraction and circulation of cold or very hot flows). The land-based tanks located near the coast, therefore also subject to salt air, will also be treated against corrosion. For Prezioso, the challenges are threefold.

First of all, there are the conditions of intervention. Anti-corrosion and insulation work is carried out day and night, often in areas that are difficult to access, dark or even inaccessible places where the installation of conventional scaffolding is impossible (insulation, inside the ship, of very hot pipes at a height of 10 metres, large size of land-based hydrocarbon tanks, etc.). Then it is necessary to adapt to the specificities of each client in terms of safety requirements, configuration of the installations or even working habits, for example in terms of electrical current. Finally, since the Chevron mobile platform to be treated is located off the northern coast of Angola, special logistics had to be put in place due to the time taken to transport the materials to a fairly isolated region.

Adaptability is therefore the watchword for Prezioso. Each new construction site has its own specific industrial configuration. Hence the need for equipment capable of ensuring this adaptability in order to make life on the construction site and its smooth running as easy as possible. It is in this context that Prezioso called on A2S for the lighting equipment required during the maintenance operations carried out on board Chevron's floating production unit.

Our approach.

Two to three months of discussions, via videoconferences and essential exchanges on the ground, in Angola, with the local Prezioso teams, were necessary to jointly develop specifications with the engineer in charge of the project and the head of the Prezioso purchasing department. These exchanges first made it possible to define the lighting needs conditioned by the number of employees working on the ship and the tasks to be carried out. Then Prezioso and A2S set about determining the number of mobile electrical cabinets required and, above all, their specific characteristics.

"Starting from a standard electrical cabinet, we built, as our discussions progressed, a tailor-made solution to make life on the construction site as easy as possible. I went to Angola to see the equipment that Prezioso was used to working with, to better understand their technical choices but also the difficulties on the ground. For example, winding large electrical cables of around twenty meters around a mobile electrical cabinet without any suitable device is not ideal. Hence the design of arms at the back of the cabinet to wind the cable correctly and easily," explains Nicolas Sevestre.

Our solution.

A2S provided Prezioso with a package including the design and manufacture of custom-made ATEX distribution/transformation cabinets4 as well as portable ATEX boxes and cabinets for lighting, ATEX LED lighting and various accessories (cables, power sockets, etc.). A stock of spare parts (including power sockets, which are often damaged on this type of construction site) was also provided by A2S and made available on the Prezioso site located in northern Angola.

The main custom-made elements of the mobile electrical cabinets supplied by A2S:

• Installation of lifting rings to make them easily transportable
• Installation of protective grilles to prevent shocks during transport or during maintenance operations
• Bar attachment at the back to allow the cable to be rolled up during storage or transport
• Arrangement of electrical outlets according to customer needs;
• Supply of changeable plastic films for ATEX and industrial lighting
• Added a handle to the lighting box to make moving it much easier.

The results.

The client knew the specific constraints that could not be met with conventional solutions offered on the market. Customization was the key to enabling Prezioso to meet its commitments. The solution provided by A2S allowed the client to obtain a point-by-point response to the problem of the construction sites that it had to implement. It was thus able to gain flexibility and productivity while ensuring comfort and safety for its workers.

1/ A floating production unit or FPSO (or Floating production storage and offloading)
It is a vessel used in the oil and gas industry for the processing and storage of hydrocarbons and the storage of oil, natural gas or oils produced at sea. Until 2017 the longest were about 310 meters long with a width of 60 meters and a hull height of 30 meters. Their production capacity could exceed 200,000 barrels per day for a storage capacity of 2 million barrels.

2/ Angola and oil
Angola, the second largest oil producer on the African continent, whose growth has reached 10% on average over the last decade, has very large oil deposits, mainly offshore. In addition, since 2013, this country has started exporting liquefied natural gas.

The products and services implemented.

ATEX LIGHTING

ATEX BOXES

Custom design