Overcoming the challenges in North Sea Oil & Gas operations with Amarinth’s pump solutions

Amarinth's approach

Investment in R&D
Amarinth invests in research and development to enhance pump design, materials, and manufacturing, ensuring durability and optimal performance in harsh conditions. The company specialises in bespoke pumps tailored to operate reliably in the low NPSH conditions encountered offshore due to limited headroom on fixed platforms and FPSOs.

Compliance and Partnerships
Maintaining a robust quality management system ensures compliance with evolving safety standards. Amarinth collaborates with customers to understand their unique challenges and tailor solutions accordingly, offering comprehensive training and support services.

Innovation and Refurbishment
Amarinth’s UK-based engineering team, offers re-engineered spares and strip, report, and refurbishment services for obsolete pumps, such as those from Girdlestone, that are common on ageing offshore assets, extending their operational life. For pumps beyond economic repair, the company’s dimensionally and hydraulically interchangeable pumps minimise downtime and costly changes to pipework and equipment.

Sustainability Initiatives
Integrating sustainability into design and manufacturing, Amarinth reduces environmental impact, incorporating renewable energy sources like its solar farm to lower carbon emissions and operational costs.

Robust Supply Chain Management
Diversified vendors, inventory optimisation, and risk mitigation ensure minimal disruptions. With a robust UK supply chain, Amarinth has been able to deliver consistently on agreed deadlines and budgets for the past two decades despite numerous economic and environmental challenges.

Seagull Development

The Seagull development, operated by Neptune Energy, is a field 17km south of the BP operated Eastern Trough Area Project (ETAP) Central Processing Facility (CPF) in the Central North Sea and has gross reserves estimated at 50 million boe.

Production from the four subsea wells will be delivered via a new subsea pipeline to the existing Heron pipeline system connected to the ETAP CPF. Gas from the development will come onshore at the CATS processing terminal at Teesside, while oil will come onshore through the Forties Pipeline System to the Kinneil Terminal, Grangemouth.

Neptune planned to double the throughput of the existing infrastructure, however the original pumps for the process were supplied by Girdlestone and are now obsolete. As identical pumps could not be purchased, Amarinth was tasked with supplying bespoke pumps to modern API 610 standards, but which matched the hydraulic performance of the existing Girdlestone pumps.

Amarinth designed and supplied two duplex feed booster pumps and two stainless steel CIP pumps which were all delivered in just 28 weeks. These were installed alongside the existing Girdlestone pumps to double the throughput of the existing processes. The new Amarinth pumps were both hydraulically and dimensionally identical to the original Girdlestone pumps, significantly minimising the cost and time that would otherwise have been required to make changes to the existing infrastructure or processes.

Brodger Field Expansion Project

Located 89 miles northeast of Aberdeen in the North Sea, the Brodgar gas condensate field posed unique challenges for pump installation and operation. Developed as a subsea satellite with a tie-back to the Britannia Bridge Linked Platform, the project demanded innovative solutions due to water depths of approximately 146m (460 feet) and limited space for installing the produced water pumps.

Amarinth was engaged to address the project's specialised requirements. Leveraging past success at Brodgar and extensive offshore experience, Amarinth engineered a tailored solution to meet the demanding needs of the site.

The bespoke API 610 OH2 pumps, featuring Plan 53B seal support systems, were designed to the newly established 12th Edition specifications. These included gusseted piping connections meeting rigorous pressure-temperature requirements, updated performance and NPSH test procedures, and refined mechanical run tests for precise oil temperature stabilisation. Amarinth also developed comprehensive head versus NPSH(A) curves to assess pump performance accurately.

To tackle logistical challenges, Amarinth integrated drive train adjustment screws for the large motor weight and installed custom noise attenuation enclosures to maintain noise levels below 77 dB, enhancing safety and comfort for onsite personnel. Certified for ATEX Zone 2 hazardous areas, the pumps underlined Amarinth's commitment to performance and safety.

Amarinth's technical expertise enabled it to overcome Brodgar's complexities, delivering reliable, efficient pumping solutions critical to North Sea offshore operations' ongoing success.

FPSO BW Catcher

The Catcher field, located 170km east of Aberdeen in the North Sea and operated by Premier Oil, features 18 subsea wells - Catcher, Varadero, and Burgman - tied back to the Floating Production Storage and Offloading (FPSO) vessel BW Catcher, which commenced oil production in December 2017.

During the initial construction phase of FPSO BW Catcher, Amarinth supplied six API 610 high-pressure, high-flow, low-shear duplex pumps. These substantial pumps, delivering an 80m head and a flow rate of 920m3 per hour, featured impeller diameters exceeding 0.5m.

The FPSO has proven highly efficient and profitable, prompting an enhanced oil recovery project to boost capacity. This initiative required six new high-pressure pumps to fit within the existing footprint, minimising modifications.

For this project, Amarinth engineered two replacement skimming pumps larger than the originals but fitting within the existing footprint. The original Plan 53B seal support systems were retained, reducing overall costs and delivery timescales.

Additionally, Amarinth upgraded the other four pumps with new casings and increased impeller diameters to enhance working pressure, minimizing modifications to existing pipework.

The new and upgraded pumps were delivered within 22 weeks, enabling FPSO BW Catcher to promptly increase capacity from existing wells. The success of this project has led to further discussions with Amarinth to identify potential upgrades to other pumps on the FPSO that could yield similar improvements.

Edvard Grieg Oil Field

The Edvard Grieg oil field is located approximately 150km off the Norwegian south-west coast in the Norwegian North Sea. The oil rig required a sampling and monitoring skid, but standard API 610 horizontal pumps with Plan 53B seal support systems struggled to fit within the platform's extreme space restrictions. Leveraging its extensive experience in designing bespoke solutions for offshore projects, Amarinth was approached to find a viable solution.

After exploring various options, it became clear that even separating the seal support system from the pump wouldn't resolve the space constraints. Recognising the importance of the pump's duty and process fluid sealing, Amarinth sought alternative approaches to reduce the system's footprint while maintaining essential functionality.

Amarinth proposed utilising one of its API 685 magnetic drive pumps instead of the original API 610 pump and Plan 53B seal support system. Unlike traditional API 610 pumps where the Plan 53B seal support system applies fluid pressure to prevent the process fluid from leaking around the mechanical seal at the pump shaft, API 685 magnetic drive pumps feature a hermetically sealed housing that contains process fluid in a closed system. Power transmission occurs contact-free through magnets from the drive shaft to the process wetted output shaft, eliminating the need for a seal support system and reducing the overall pump and motor assembly length.

By opting for an Amarinth API 685 magnetic drive pump, the required duty could be maintained while significantly reducing the pump's footprint to fit within space constraints. Manufactured in super-duplex stainless steel to NORSOK M650 specifications, Amarinth delivered the pump within 28 weeks, including witness testing.

Amarinth's innovative solution not only addressed the project's challenges but also ensured optimal performance and reliability in the demanding offshore environment of the Edvard Grieg oil field.

Mariner Oil Field

The Mariner oil field, situated on the East Shetland Platform of the UK North Sea, approximately 150km east of the Shetland Islands, required a specialised API 610 pump skid package for a water treatment plant. Amarinth, renowned for its expertise in offshore skid design and packaging, was chosen for this challenging project.

The task was demanding as the package had to fit within a pre-defined footprint of 3.6m x 1.5m, with all components, including the pump, seal support system, pipework, monitoring, and ancillary equipment, contained within. Furthermore, delivery was required in just 38 weeks.

The limited space posed three main challenges for design engineers:

- Complex pipework routing to minimise losses.

- Ensuring no additional loads or movement impacted existing platform pipework.

- Maintaining serviceability around the skid package.

Detailed technical calculations and finite element analysis were employed to address these challenges. To ensure the pump package could meet the stated duty, the constrained pipework assembly underwent rigorous evaluation to account for potential frictional losses. Furthermore, a custom sliding baseplate with a PTFE layer was engineered to isolate equipment movement during operation.

Additional features included a flow meter and low flow bypass control valve for pump protection during low flow conditions, along with heat tracing for frost protection. Human factor software simulated operator and maintenance engineer movements around the skid, ensuring accessibility to all components.

Amarinth's engineering agility and problem-solving approach facilitated the delivery of a bespoke pumping solution within the tight deadline. The successful completion enabled the water treatment plant to meet its build schedule, demonstrating Amarinth's commitment to overcoming challenges and delivering on-time solutions in the demanding offshore environment of the Mariner oil field.

Dan Oil Field

The Dan oil field, located approximately 120 miles west of Esbjerg in the Danish sector, is among the largest North Sea chalk fields. Developed across 12 platforms, the field features 38 active oil wells and 33 active water injectors, meeting the dynamic demands of the oil and gas industry through phased development.

Three critical Girdlestone 980 API 610 pumps on the Dan Fox platform, integral to the oil and water cyclone separator system, had reached their end-of-life. With Girdlestone no longer in operation and their pumps obsolete, the challenge was to seamlessly replace them without extensive modifications to existing pipework and fittings, Typically, fitting new pumps involves costly and time-consuming adjustments and changes which also can also lead to significant production downtime.

Leveraging its expertise in replacing Girdlestone pumps, Amarinth proposed a bespoke version of its own centerline pump. This tailored solution not only met the required duties but also matched the API 610 edition of the original Girdlestone pump. Crucially, it was dimensionally interchangeable, reducing the need for modifications to associated infrastructure and equipment.

Manufactured to ATEX requirements with Plan 31 seal arrangements and associated gauges, the bespoke pumps were completed within a short 26-week lead time. This aligned with the required maintenance window, ensuring minimal disruption to the continuous operation of the Dan Fox platform.

Amarinth's ability to deliver a seamless replacement solution underscores its commitment to providing efficient and reliable pumping solutions tailored to the specific needs of offshore operations in the North Sea.