Socotherm Brasil contributes to the Petrobras PDET Project, optimizing costs and job completion.

Since 62% of the brazilian oil production is done in water depths ranging from 980 to 5,900 feet, Petrobras has turned to be the major offshore producer.

Due to this key factor, Petrobras has developed a high standard of technological requirements, which demands innovation and specific solutions from its suppliers. Job completion in tight schedules and cost effective operations along with environmental protection and safety conditions are the essential requirements to meet.

PDET Project (Plano Diretor de Escoamento e Tratamento, as it is named in portuguese) designed by Petrobras is a clear example of these challenges. TenarisConfab, Corus, Technip and Socotherm Brasil were some of the companies involved in the PDET Profundo stage.

The english translation of the PDET abbreviation is quite illustrative of the scope and goals of this project: Oil Outflow and Treatment Plan. Even more, if we consider its focus area: Campos Basin, source of 84% of the brazilian oil production and a total investment plan expected to reach   u$2,260 billion. In terms of jobs, 34,000 workers will be hired during the building stage and 3,750 for its operation.

After being finished, PDET will produce 630,000 barrels per day. Therefore, Brazil will consolidate its national self supply policy, with an oil production of 2.220 barrels per day in 2007, even with surplus for exportation.

At the beginning, PDET foresaw the construction of an oil pipeline connecting the Campos Basin with the refineries in the Sowtheast Region of the country. Finally, after many observations made by the Rio de Janeiro Government, a mixed solution was adopted combining various transporting ways: oil pipelines and vessels to the São Sebastião Terminal; and existing onshore oil pipelines to refineries.

The functioning of this system is quite simple and involves five Petrobras platforms working together as PDET Profundo system. The collection platform PRA-1, settled in shallow waters (330 feet depth) 62 miles offshore, will receive production from five platforms through individual oil pipelines –P-51 (Campo de Marlim Sul), P-53 (Campo de Marlim Leste), and P-52, P-55 and Module-4 (Campo de Roncador)–, located in deep waters of up to 5,900 feet depth approximately.

The following step, will be oil bombing from PRA-1 to FSO and the monobuoys, where the oil vessels will pick up the oil that will be carried to the terminals in Río de Janeiro (Baía de Guanabara and Angra dos Reis) and São Paulo (São Sebastião).

From those terminals, the oil will be transported to the refineries in Minas Gerais (Regap) and Rio de Janeiro (Reduc), or will be distributed to the refineries in  São Paulo (Revap, RPBC, Recap and Replan), through existing pipelines.


Construction experience

The first alternative considered by Petrobras was the installation of deep water pipelines connecting PRA-1 with the five platforms using 40 feet pipes welded on board, as a previous step. This process would lead to higher operation costs and longer project terms.

Overcoming this hurdle was the task requested to Socotherm Brasil, subsidiary of Socotherm Americas and member of the Italian Group Socotherm, based in Vicenza.

The goal of the solution proposed by Socotherm Brasil was the optimization of the time frame and resources by carring out the assembling and welding process of 80 feet “double joints” in an onshore plant, instead of doing it offshore.

 

The advantages of this solution are based on:

 

• higher efficiency on the welding process, allowed by the use of hydraulical and motor equipment  in the production line that guarantees the alignment of the welded pipes (alignment structures - Hi/Low of 0.04” and coupling - straightness of 0.984” every 80 feet roughly); and
• the  possibility to apply anticorrosive and thermal coating  on pipes with different geometry (J-lay collars and Buckle arrestors) with the use of  Multipass® side extrusion technology , developed by Socotherm Americas.

 

The works for PDET Profundo began on the stretch connecting the semi submergible platform P-52 to PRA-01. TenarisConfab and Corus were responsible for the supply of 24 and 17 miles of 40 feet pipes, respectively.

Having the possiblility to assemble and coat double joints Socotherm Brasil applied a thermal coating of Wetisokote Solid Propylene on the pipes supplied. The pipes were of 18” diameter, X60 grade and WT ranging from 0.625” to 1.125”.

The Wetisokote® solid propylene is obtained from an exclusive Socotherm Americas formula, which is adjusted to the specific project needs and applied over the anticorrosive propylene protection by means of Multipass® side extrusion technology. This methodology allowed a coating thickness of 2.05” over pipes 80 feet long.

The choice of this coating was due to the need of avoiding the damaging effects of paraffin deposition and/or hydrates inside of the pipe. Thus, the oil flow from the platforms is protected along the whole life of the project. Besides, compared to other similar standard materials, this coating has a better technical performance and it is even more cost effective.

The coating process was carried out in a strategic area close to Petrobras operations zone, specifically, in the Socotherm Brasil marine base located in Ponta de Ubu (Espirito Santo). This was a key factor in the optimization of the logistical dimension.

Finally, the installation of the thermally insulated 18” rigid line and the risers, was carried out by Technip’s deepwater pipelay vessel Deep Blue, using the J-Lay deployment method.


Conclusion

In summary, Socotherm Americas coating technology associated with “double joints” operation has provided Petrobras an impressive economy in terms of project time and cost, without mentioning an increment of entire pipeline coating quality. The best evidence of this economy is the reduction in 50% of all Field Joint Coating, since half of the joints had been coated during double joint coating process.

Regarding project time cost benefits, we can highlight the schedule reduction of 50% during pipe laying barge installation, due to the fall in the number of offshore joints required to half of conventional joints quantity. About quality issues, it is easy to conclude that in comparison with a standard project, a flowline fabricate based on coated double joints presents more continuity in terms of thermal and anticorrosion properties, since the weak points have been reduced in 50%.

Therefore Socotherm Brasil is helping Petrobras to complete satisfactorily this first project stage that is targeted to change the energetic matrix of Brazil.  


Project Scope

Socotherm Brasil scope of work for the PDET Profundo project consisted in the supply of anticorrosion and thermal insulation coating for export line, as follows:

Export  Line

Pipe OD 18” in (457.2 mm) – Pipe Wall Thickness 0.625” –  1.125”
Steel grade: X60
Pipe quantity: 215.220  feet

 

Source: Socotherm, Buenos Aires, April 2007