January 07, 2016

Case Study

Apache North Sea Forties Project


Tata Steel helped oil and gas company Apache North Sea win a race against time by delivering urgently needed coated line pipe as part of the customer’s North Sea Forties project.

The challenge

Tata Steel had to work intensively to understand the customer’s exact needs, then effectively manage the complete supply chain. The product had to be delivered ready-to-lay within just 10 weeks to enable Apache to complete a physically tough and technically complex North Sea project.

The solution

Tata Steel took an innovative approach to the use of high frequency induction (HFI) steel line pipe to create tangible commercial benefits for Apache. These included a shorter procurement schedule and significantly superior product quality.

The product

More than 1,000 tonnes of steel slab were cast before being hot rolled into coil at Tata Steel’s Strip Products facility in Port Talbot, South Wales. The steel coil was then cold formed and HFI weld was created with no filler material or direct electrical contact.


Companies with maturing assets in the inhospitable environment of the North Sea must regularly and rigorously review the integrity of their infrastructure.

When assets show signs of deterioration, the race is on to upgrade them so the operator can continue to access valuable oil and gas reserves. This means the speedy and efficient supply of high quality, cost-effective pipeline solutions is vital to commercial success.

Pipeline inspection reveals need for urgent replacement

Apache North Sea bought the North Sea Forties Field – 178 km north east of Aberdeen – in 2003 and has since doubled production.

Infield pipelines are critical assets for exporting oil production and Apache carried out a number of inspection programmes to assess the condition of the network. The examinations confirmed:

  • 17 years since the last internal inspection of the pipeline
  • Extensive corrosion present
  • 2.5 year estimated remaining life for the pipeline
  • Leak corrosion damage at the deepest defects was most likely area of future failure

Race against time begins

As a result, Apache contracted Tata Steel to fabricate, coat and deliver 5.25km of high frequency induction (HFI) steel line pipe.

This had to be completed in an extremely tight time frame of just 10 weeks in order to meet a lay vessel window of opportunity.


Tata Steel worked closely with subsea engineering and management contractors JP Kenny Caledonia, who designed line pipe with a lifespan of 20 years, in accordance with PD 8010 Part 2.

From this design, 5,400m of 14” (355.6mm OD) line pipe was fabricated, coated and delivered in nine weeks.

Precise organisation crucial to success

The urgency of the project and the specific steel chemistry required:

  • More than 1,000 tonnes of steel slab to be cast before being hot rolled into coil at Tata Steel’s Strip Products facility in South Wales
  • Efficient transport of the steel coil to Tata Steel’s high frequency induction (HFI) mill in Hartlepool
  • Pipe to be cold formed from steel strip
  • The creation of the HFI weld with no filler material or direct electrical contact

High quality product delivered ahead of schedule

Rigorous non-destructive testing (NDT) was carried out on the line pipe to ensure integrity before it was cut to the required length. The pipe joints were then:

  • Coated by BSR Pipeline Services with three-layer polypropylene
  • Delivered for spooling onto an Apache lay vessel

Technical precision creates world-class solution

The pipe was not only delivered three days ahead of the challenging schedule, but was above the contracted specification. This significant accomplishment involved:

  • The coating of the field joints using mechanised three-layer polypropylene tape with flame sprayed polypropylene (FSPP) on all repair welds, flanges and onshore tie-in welds
  • The completion of the stalks a day after the final line pipe joints arrived

The importance of really knowing the customer

Neil Scott, operations manager of Tata Steel’s HFI mill said: “To meet this demanding project schedule it was essential to have a high level of transparency of Apache’s problem and the challenges they were trying to overcome. By understanding the customer’s business at both technical and commercial levels, we maximised performance and efficiency.

“This working relationship is an excellent template for other operators and contractors and would allow companies in the North Sea – where project life cycle is much shorter – to complete projects more efficiently, cost-effectively and with quality and safety as the over-riding priority.”

Enabling the customer to see substantial benefits

The innovative use of HFI for Apache offered a number of key benefits, including:

  • A consistently shorter procurement schedule
  • Superior ovality and wall thickness tolerance compared to seamless line pipe
  • Reduced costs at the design and installation stages
  • Maintaining exceptional product integrity

In addition, enhanced quality and specification gave Apache notable commercial advantages, such as:

  • An exceptionally robust product, engineered to meet demanding application requirements
  • Improved performance of the pipe over its lifespan

The professionalism and dedication of the Tata Steel team ensured that this project was completed ahead of schedule and delivered to our exact specification. Their commitment delivered outstanding results on time and within budget.

Mark Richardson, subsea projects manager at Apache North Sea.