Learning to be lean in the subsea sector

John Bradbury

May 1, 2016

John Bradbury speaks with ExxonMobil’s Marilyn Tears ahead of her presentation at this year’s Underwater Technology Conference in Bergen, Norway.


Marilyn Tears has already made her mark in the offshore energy sector as senior project manager for the ExxonMobil-operated Julia deepwater development in the US Gulf of Mexico (GoM), which is due to start production this year.

Julia was discovered in 2007 and with an estimated 6 billion bbl of oil in place in the Walker Ridge area of the US GoM, the field is being developed at an investment cost of more than $4 billion. The initial development phase includes six wells tied back subsea to the Chevron-operated Jack/St. Malo semisubmersible floating production unit (FPU).

After that challenge, in April 2015 Tears took on a new role as Safety, Security, Health and Environmental manager for ExxonMobil Development Co. It is that health, safety and environmental (HSE) perspective that she will share at this year’s Underwater Technology Conference (UTC) in Bergen in June. The conference theme will be “Lean subsea – the way forward.”

“How we manage and lead health, safety and environmental issues sets the stage for how we manage all other aspects of business in the subsea sector,” Tears says. “We often see HSE as a predictor of cost, schedule and quality performance. HSE can serve as a bonding point for establishing relationships that lead to higher levels of trust and teamwork in every part of the business. This is why excellence in HSE is important through the entire life-cycle of subsea projects.”

Tears continues: “Development teams need to think through all aspects of HSE and understand the implications for design, manufacturing, installation, operations, maintenance and abandonment. HSE design solutions that are both excellent and fit-for-purpose will ultimately reduce cost across the life-cycle of subsea equipment. Focus on structure and consistency for work execution is not only key to improving safety, reliability and quality, but it will also remove execution variability, which therefore reduces rework and extra costs,” she adds. “There have been many scientific studies that conclude improving safety and quality leads to improved cost control.”

And at this year’s UTC, Tears will expand on the theme of leaner operations: “Being ‘lean’ is about creating more value for customers with fewer resources. A lean organization understands customer value and focuses its key processes to continuously increase that value. By eliminating efforts that do not add value to customers, costs will be reduced,” Tears states. “Looking at technologies across a system to reduce waste in the entire system with multiple vendors will improve value to customers. To become leaner, it is important to focus on the high-risk areas as they drive execution uncertainty. Teams that gain clarity around what is required to address these high-risk areas are rewarded with improved performance.”

Specifically on cost, Tears says the industry needs to work “appropriately and collaboratively to figure out how to get leaner and adapt to meet market and industry development needs. We must continue to use lessons learned to improve performance and support new challenges of higher pressure and deeper water depths. Leveraging learnings from others contributes to identifying risks, as well as potential savings.”

Tears advocates the use of creative thinking when adapting the deployment of common components in different configurations, which may provide lower cost alternatives to unique, purpose-designed and built solutions. Additionally, industry focus on how to use subsea technology to enable alternative subsea solutions to save costs over traditional surface solutions may bring “leaner” development options.

Industry standardization has already been embraced by the subsea sector, despite its relatively short history, and Tears believes that real inroads have been made. “A good example is the Det Norske Veritas (DNV) Subsea Forging Standard that has recently been published,” she says. “There are additional joint industry projects progressing efforts in the areas of subsea quality, subsea welding standards, documentation, topside control systems and electrical power systems.” The International Association of Oil & Gas Producers (IOGP) is beginning an effort to standardize designs for the four primary types of subsea trees used in the world today. “I am proud to say that ExxonMobil has played key leadership roles in many of these initiatives to date,” she adds.

The DNV Subsea Forging Standard provides a recommended practice for steel forgings for subsea applications and was developed with 21 companies – operators, contractors and manufacturers in a joint industry project, and sets out qualification, manufacturing and testing requirements for carbon and low alloy steel forgings. DNV said the recommended practice allows less equipment lead time, better stock-keeping and interchangeability of forgings, while improving and maintaining quality.

Although none of the recent standardization work was available for the Julia development, Tears says, ExxonMobil developed standard part numbers with several suppliers on a concentric, monobore vertical tree design, which was used for both the Hadrian South and Julia projects. “ExxonMobil’s ‘Universal Master Control Station’ was also used for the first time on Julia, and is the precursor of standardized subsea and topside controls interfaces,” Tears adds. “In the future, subsea controls may be nothing more than a node on a conventional topside (or onshore) process control system.”

Looking ahead, Tears says, “ExxonMobil will continue to focus research and development efforts on supporting our portfolio outlook in challenged resource development areas, and capturing capital expenditure savings associated with infrastructure reductions for offshore opportunities. ExxonMobil has recently qualified subsea processing technologies in the areas of compression, subsea separation and subsea water treatment.” Tears says, “We support further work to extend these technologies to include potential applications for wet gas compression, high pressure boosting and long-distance subsea power distribution and transmission.” According to Tears, ExxonMobil has begun researching subsea gas dehydration, and it is evaluating opportunities to marinize ExxonMobil’s proprietary compact dehydration technology, cMist, for subsea gas fields.”

Tears is energized by industry efforts to get leaner and believes that “getting leaner while meeting current development needs will take an examination of the way subsea systems work together – from design through abandonment – to remove inefficiencies. This will take open conversations between customers and suppliers, as well as active discussion and debate on priority needs and potential options to meet those needs across development phases while maintaining focus on safety, quality and reliability of products and execution.”