Hydraulics in the Marine Sector

Hydraulic systems play an important role across the marine industry, providing the force and control required for equipment operating on ships, vessels and marine infrastructure. From steering and propulsion to dredging and cargo handling, hydraulic equipment can be found throughout marine operations. However, hydraulic systems operating in marine environments face conditions that can be considerably more demanding than those found in many land-based applications.

Saltwater, humidity, corrosion, vibration, temperature changes and limited access to equipment can all affect system reliability. For marine operators, selecting the right components and having access to responsive hydraulic support can therefore be essential.

Where Are Hydraulics Used in the Marine Industry?
Hydraulics are used in a wide range of marine applications because they can provide high levels of force and controlled movement from relatively compact equipment.

Common applications include:
• Steering systems
• Propulsion systems
• Dredging equipment
• Cargo handling
• Deck machinery
• Lifting equipment
• Winches
• Cranes
• Hatches
• Marine access equipment

Fluid Power Services identifies steering, propulsion, dredging and excavation, and cargo handling among the key marine applications it supports.

Why Are Hydraulics Suited to Marine Applications?
Marine machinery often needs to produce significant force while operating within limited available space. Hydraulic systems offer several characteristics that make them suitable for these environments.

High Power Density
Hydraulics can transmit significant power through relatively compact components. This is useful on vessels where available machinery space is limited.

Controlled Movement
Hydraulic valves and control systems allow operators to regulate movement and force. This can be important for applications such as steering, lifting and cargo handling.

Flexible Installation
Hydraulic power can be transmitted through hoses and pipework, allowing components to be positioned in different areas of a vessel. This can make hydraulic systems practical where mechanical transmission would be difficult to install.

The Challenges of Marine Hydraulics
Operating at sea creates additional challenges for hydraulic systems.

Corrosion
Saltwater and humid environments can accelerate corrosion of exposed components. Material selection therefore becomes particularly important. Depending on the application, corrosion-resistant materials and appropriate protective measures may be required.

Vibration
Marine machinery can be exposed to significant vibration. Vibration can contribute to:
• Fitting loosening
• Hose movement
• Component wear
• Pipework fatigue
• Leakage
Correct installation, support and hose routing are therefore important parts of hydraulic system reliability.

Temperature and Environmental Exposure
Marine hydraulic systems may experience changing temperatures and environmental conditions. The hydraulic fluid, seals, hoses and other components need to be appropriate for the expected operating environment.

Restricted Access
A component that is relatively easy to access in a factory may be considerably more difficult to reach on a vessel. This makes maintenance planning particularly important.

Choosing Hydraulic Components for Marine Use
The correct hydraulic component depends on the application.

Hydraulic Hose
Marine hydraulic hoses need to be correctly specified for pressure, temperature, fluid compatibility and environmental conditions. Hose routing should also minimise excessive movement, abrasion and contact with hot or sharp surfaces. Fluid Power Services provides made-to-measure hydraulic hose assemblies and has extensive experience supplying and assembling hydraulic hose solutions.

Hydraulic Fittings
Fittings need to be correctly rated and compatible with the hose and system. Material selection can also be important where corrosion exposure is significant.

Hydraulic Valves
Valves control the direction, pressure and flow of hydraulic fluid. The correct valve configuration depends on the specific application and control requirements.

Hydraulic Cylinders
Cylinders convert hydraulic energy into linear mechanical movement and can be used for applications including lifting, positioning and actuation. Marine cylinders need to be specified around the load, stroke, pressure and environmental conditions involved.

Hydraulic Pumps and Motors
Pumps provide the hydraulic flow required by the system, while hydraulic motors convert fluid power into rotary mechanical output. Correct sizing is important to ensure that the system provides the required performance without unnecessary energy consumption or component stress.

Hydraulic Cleanliness at Sea
Hydraulic contamination can cause premature component wear and system failures. This can be particularly problematic in marine applications because repairs may be more difficult once a vessel is operating. Keeping hydraulic fluid clean and maintaining appropriate filtration can help protect pumps, valves and other precision components. Maintenance procedures should also minimise the risk of contamination entering the system during hose or component replacement.

Maintenance Is Critical for Marine Hydraulic Systems
A hydraulic failure at sea can be extremely disruptive. Depending on the vessel and application, a failure could affect:
• Vessel manoeuvrability
• Cargo operations
• Dredging
• Lifting operations
• Production
• Crew safety
• Scheduled operations
For this reason, planned maintenance and inspection should form part of the overall hydraulic management strategy.

Hydraulic Repairs and Emergency Support
Marine operators need access to engineering support when problems occur. Fluid Power Services has provided hydraulic products, services and call-out repairs to ships for more than 35 years and is based on Liverpool docks, positioning the company to support marine customers. Its mobile service provides on-site hydraulic maintenance and repair, with engineers able to manufacture hydraulic hose assemblies on site where appropriate. This can be particularly valuable when transporting a vessel or large piece of equipment to a workshop is impractical.

Traceability in Marine Hydraulics
Traceability can be an important consideration when maintaining hydraulic equipment. Knowing what hose or component was installed, when it was supplied and what testing was carried out can make future maintenance and replacement easier. Fluid Power Services provides traceability for hoses and field products and can provide certificates of conformity and pressure test certification where required. This provides a documented record that can be useful for maintenance and asset management.

Marine Hydraulic Systems and Safety
Marine hydraulic equipment can operate under high pressure and control substantial mechanical forces. Maintenance should therefore be undertaken by appropriately trained personnel using suitable procedures. Before working on hydraulic equipment, systems should be isolated and depressurised in accordance with the applicable equipment and site procedures. Particular care should be taken with stored hydraulic energy and accumulators. Hydraulic injection injuries are also a serious hazard. Even a small pinhole leak can produce a high-pressure jet capable of penetrating skin.

Why Choose a Specialist Marine Hydraulics Supplier?
Marine hydraulic systems are not simply standard industrial hydraulic systems installed on a boat. The environment, operating conditions, space restrictions and consequences of failure all need to be considered.

A specialist supplier can help with:
• Component selection
• Hydraulic hose assemblies
• System maintenance
• Fault finding
• Emergency repairs
• Replacement components
• Engineering support
• Asset management
• Traceability

Fluid Power Services has supported marine customers for more than 35 years and offers hydraulic products, maintenance, repairs and mobile call-out services.

Keeping Marine Hydraulic Systems Reliable
Reliability at sea begins before equipment fails. Correct component selection, appropriate installation, regular inspection, hydraulic cleanliness and planned maintenance can all contribute to dependable hydraulic system performance. Having access to responsive engineering support is also important when an unexpected failure occurs.
For vessels and marine equipment where hydraulic systems are critical to operation, a proactive maintenance approach can help identify potential problems before they become disruptive failures.

Marine Hydraulic Support from Fluid Power Services
Located on Liverpool docks, Fluid Power Services has extensive experience supporting the marine sector with hydraulic products, maintenance, engineering and emergency repair services.

From hydraulic hoses and fittings to pumps, motors, valves and cylinders, the team can support a wide range of marine fluid power requirements.