Seatools is a one-stop-shop on subsea hydraulics, subsea hydraulic components and complete systems
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Industrial quality subsea hydraulic solutions


From components such as compensators to complex custom-engineered subsea (electro-) hydraulic systems

Seatools offers a full range of subsea hydraulic services and products. Our product range includes a wide array of subsea hydraulic components, such as compensators, filters, and thrusters. For more than 15 years we have successfully applied these components to the subsea vehicles we deliver, some of which operate under the harshest of conditions.

In addition to components, Seatools delivers full-fledged hydraulic systems. Because underwater hydraulic systems run in tandem with the electric, mechanical, and control segments of a system, at this very crossroads Seatools’ multidisciplinary engineering approach offers great value. Properly devising a system requires a capable system integrator with knowledge of all disciplines concerned. The heave-compensated gangway project is an outstanding example of Seatools’ ability to fulfill this role. Facilitated by our advanced simulation capabilities, we successfully integrated all concerned engineering disciplines.

  • Subsea hydraulic components (also Pressure-Balanced, Oil-Filled (PBOF))
  • Subsea (electro-)hydraulic systems such as SHPUs, reservoirs, and ROV hydraulics
  • Advanced simulations of subsea (electro-)hydraulic systems
Value creation
  • Combining standardized components with strong engineering capabilities
  • Minimal lead and commissioning times thanks to advanced simulations
  • Environmentally friendly systems thanks to biodegradable oils
Track record
  • Delivered numerous (ROV) hydraulic components and systems
  • Performed numerous advanced simulations of (electro-)hydraulic systems
  • Delivered hydraulic systems for subsea production systems

By using hydraulic components as building blocks combined with our engineering capabilities and extensive experience, we deliver highly reliable, cost-effective hydraulic systems in short time frames. Want to learn more?


  • Feasibility, conceptual design, and engineering studies
  • Delivery of subsea hydraulic components
  • Delivery of hydraulic systems
  • Maintenance, repair, and upgrades
Feasibility studies on subsea hydraulic systems

Combining experience with distinguished engineering capabilities

The merger between our extensive knowledge base and experience in the field of subsea hydraulics and our multidisciplinary engineering capabilities enables us to perform high-quality feasibility, conceptual design, and engineering studies. During studies, we can deploy our simulation capabilities in order to investigate concept feasibility, failure modes, and concept performance testing. As is shown by the subsea storage control fluid engineering study, our strongly innovative capacities create value in the context of this type of study in particular.

Delivery of underwater hydraulic components

Component designs based on more than 15 years of field feedback

We deliver standardized and custom-made subsea hydraulic components. The scope of our underwater hydraulic components includes compensators, filters, thrusters, pressure pods, and valve boxes. Many of our components are deployed in the subsea vehicles we build, and their designs are based on many years of experience and field feedback.

Delivery of fully fledged subsea hydraulic systems

From related systems to full-fledged, turnkey systems

Seatools designs and delivers full-fledged, custom-built subsea and offshore hydraulic systems that can incorporate all related systems, including the electric, mechanical, and control systems. As system integrator we do not only design and deliver the hydraulic system – we also supply the sensors, actuators, power supply structure, and controls of a system. Our advanced simulation capabilities facilitate accurate predictions and system performance optimization, and thus minimize offshore commissioning times. Our ROV hydraulic (control) systems and the OAS heave-compensated gangway control system are eminent examples of how Seatools can empower your operations.

Maintenance, repair and upgrades on underwater hydraulics

Continue or extend the performance of your subsea hydraulic system

Seatools performs maintenance, repair, and upgrade activities on self-manufactured and third-party manufactured subsea hydraulic systems.


  • Pre-optimized hydraulic systems that minimize commissioning times and operational risk

    Pre-optimized subsea hydraulic control systems

    Because we combine hydraulic control system development and advanced simulations, our hydraulic control systems are delivered with pre-programmed, close-to-optimal controller settings. An offer that has proven to generate great value, as it significantly reduces expensive on-site commissioning times and delivers highly accurate control systems. In addition, failure-case simulations allow us to develop controllers that guarantee fail-safe behavior, significantly reducing operational risk.

  • Combining standardized components with strong engineering capabilities

    Seatools subsea hydraulic components building blocks

    Our value proposition for subsea hydraulic systems combines our hydraulic component range with multidisciplinary engineering capabilities as well as an extensive in-house experience base in the area of underwater hydraulics. Our standardized components function as building blocks of a hydraulic system, while our engineering capabilities and experience ensure that all performance criteria are met in an efficient way. A rare combination, that results in highly reliable, cost-effective, and first-time-right systems that can be delivered within a short period of time.

  • Environmentally friendly systems thanks to biodegradable oils

    Biodegradeble oil in ROV hydraulic system

    Over the past years, demand for biodegradable hydraulic fluids has increased thanks to their reduced environmental impact in case of hydraulic emissions. Seatools is able to design and deliver hydraulic systems that run on biodegradable oils.

Pre-optimized subsea hydraulic control systems

Would you like to discuss your project? Our experts gladly discuss and advise on potential solutions for your project.

Standardized hydraulic components and systems

Field-proven hydraulic components and systems

  • Subsea HPUs
  • Subsea compensators and reservoirs
  • Valve boxes
  • Pressure pods
  • Hydraulic thrusters
Standardized subsea hydraulic power units including pressure compensation 2022

Subsea hydraulic power thanks to standardized and custom-made subsea HPUs

Seatools develops and delivers both standardized and custom-made subsea hydraulic power units. Our standardized subsea power units are field proven, highly reliable subsea power packs that can be applied to a wide range of subsea applications.

In the event of case-specific applications or requirements, Seatools can provide made-to-order subsea hydraulic power units. We have delivered subsea HPUs in a wide variety of configurations, and with power ratings ranging from 0.2 kW to 400 kW. Our custom-built power units can be designed to include any specification.


Custom subsea compensators and reservoirs

Standardized and custom-built subsea hydraulic compensators and fluid reservoirs

Seatools offers a full range of subsea pressure compensators and reservoirs: from basic 0.6-liter lightweight compensators, to large-volume, permanently subsea-situated hydraulic reservoirs with an MTTF of more than 20 years.

Next to our three standardized compensator series, we design and deliver custom-made compensators and fluid reservoirs, optimized for your needs.


Subsea hydraulic valve boxes


In order to safely house and operate hydraulic valves in subsea environments, Seatools designs and manufactures subsea valve boxes. Our high-end valve boxes are characterized by their robustness and effectiveness, which is facilitated by remote I/O control functionality. Our valve boxes are oil filled and pressure compensated so as to minimize weight and size.

Our subsea valve boxes come in a wide variety of possible configurations, with variations in connector configurations, valve types, materials, and connectivity options.

Subsea hydraulic pressure pod


Our subsea pressure pods are dedicated measurement bodies able to measure pressures at various points across a hydraulic system. The creation of a separate measurement body increases reliability as the remaining part of the electronics are kept at a safe distance from hydraulic fluids. We applied our pressure pods across our ROV systems in a wide variety of configurations.

Subsea hydraulic thrusters

A range of field-proven subsea hydraulic thrusters

Seatools offers a range of reliable hydraulic thrusters for subsea vehicle applications. Our thruster systems are full-fledged assemblies that include the arrangement of the drive. They are proven designs that have been incorporated in many of our fall pipe ROVs. Not only do we supply the hardware of the thruster itself, we can also perform subsea vehicle propulsion design engineering.





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