Successful shipyards use Roxtec for the next-generation vessels

The International Maritime Organization (IMO), safety organizations and shipyard customers require a drastic reduction of greenhouse gas emissions. Going forward, shipyards must master the art of building and rebuilding carriers and tankers to enable the green energy transition. Using flexible cable and pipe seals can make it easier to prepare for the introduction of clean marine fuels.

Safety challenges associated with sustainable marine fuels

The shipbuilding industry will convert engines, deploy dual-fuel and fuel-flexible engines, and use different renewable biofuels. There may be more than one type of fuel per ship. It can be combinations of liquefied natural gas (LNG), liquefied biogas (LBG), ammonia, hydrogen, methanol, ethanol, methane, hydrotreated vegetable oil (HVO), fuel cells, or wind, solar or nuclear power. Some low carbon and zero-emission marine fuels that are alternatives to conventional petroleum fuels mean new safety challenges within bunkering operations, onboard fuel storage, fuel distribution, and maintenance. Vessels need closed compartments and security zones separated by tight fire and safety barriers to handle different types of fuels and avoid the risk of gas leakage or cargo fire. There are thus reasons for exploring safe, reliable and flexible cable and pipe transits.

Certified cable and pipe transits for multi-hazard protection

Roxtec cable and pipe transits have been used by leading shipyards for decades. The robust seals are made of materials that withstand harsh environments, and they are developed and certified to protect against multiple hazards, including fire, gas, water, and the risk of explosion. The seals are fire rated to strict international standards to prevent the spread of fire to the next compartment through cable and pipe penetrations. They are gas-tight to maintain the integrity of fuel systems, prevent hazardous situations and ensure safe operations. And they are watertight to protect critical systems onboard from water ingress, humidity and operational failure.

Class recommendations and guidelines regarding green fuels

Several alternative fuels have properties which require a more complex fuel containment system than conventional fuel oils. Each alternative fuel has its unique associated hazards. Here are some examples of regulations and recommendations from DNV, BV, ABS, Class NK and CCS documents:

• Ammonia is corrosive, toxic, flammable and explosive. Safety concepts must consider toxicity, fire and explosion risks to protect crews and aquatic life. Fuel storage, fuel-preparation rooms, and energy-conversion systems must be designed to guarantee safety. Hazardous areas and security zones need to match the ignition characteristics of ammonia.
• Methanol has a wide flammability range. It is toxic, with limits for human inhalation, exposure and skin contact. It must not leak in confined spaces or on deck. The flames are nearly invisible until they have spread to materials nearby. Due to the corrosive properties, special consideration must be given to for example piping fixtures.
• Hydrogen is explosive and has a wide flammability range which increases when mixed with air. A hydrogen leak can be a serious fire hazard due to the quick formation of flammable gas mixture. The flames are invisible and hard to detect. Hydrogen burns quickly compared to other flammable compounds. Safety during handling and storage is crucial.
• Ammonia and natural gas have boiling temperatures that do not correspond to conventional storage tanks. Both fuels need a storage and supply system that can manage pressure increase and boil-off gas. This is important for the choice of construction materials. Natural gas shall not leak, because ignition of leakages in enclosed spaces may result in explosions and fire. 

Roxtec supports shipyards with sealing and protection expertise

Roxtec is a trusted technical advisor and supplier of modular-based sealing systems to the shipbuilding industry. Roxtec is also a sealing partner within industries dealing with hydrogen, batteries, energy storage, and wind, solar and nuclear power – all with high safety demands and need for operational reliability. Therefore, Roxtec sealing experts have the experience and knowledge shipyard designers and installers need to handle the new challenges. Roxtec can help reduce the risk of emissions and avoid environmental catastrophes or loss of life and assets.

The need for fire protection, gas-tightness, and watertightness

Additional safety barriers, such as double barriers, area segregation, and isolation design concepts, are needed to mitigate risk. Double barriers, such as fuel-preparation rooms and double piping arrangements, shall be enclosed in airtight and watertight fuel connection storage hold spaces.

• Fuel-preparation rooms must be gastight and watertight, and bunkering stations must be surrounded by gastight boundaries to enclosed spaces. The fire integrity of the fuel-preparation room boundaries must be shielded by A-60 class divisions. Bunkering stations shall be separated by A-60 class divisions towards machinery and high fire risk spaces.
• Risk management must already during planning and construction consider fuel flammability and ignition energy. There is a need for updated onboard methods, operational manuals, and review of educational programs across all fuels to ensure safe handling, appropriate standards and safety mechanisms.

Roxtec has the experience and knowledge to handle the hazards

Many customers turn to Roxtec for help with developing and testing fit-for-purpose solutions to maintain safety at sea. Roxtec has, for example, a strong record of developing and testing seals that meet new maritime demands, such as non-welding solutions and seals that maintain tightness performance after a fire has occurred (according to SOLAS regulations). Shipyards can count on Roxtec for technical support and class approved cable and pipe transit installation quality inspections in, for example, safety barriers. The goal is to assist shipyards so that they can hand over completely safe and future-proof retrofit-ready vessels to the owners.

The importance of ensuring classification society compliance

Since 2021, class requirements call for systemized control, documentation, and inspection of watertight cable transits. Cable and pipe penetrations must not ever be a weak link in any design for safety barriers. To ensure long-term safety and functionality in closed compartments and security zones, it is crucial to choose, specify and use certified cable and pipe transits and to install and maintain them properly.