Fire protection is a critical part of onboard safety in the harsh environments presented by the offshore world. Reducing the risk of fire hazards is a vital and challenging part of designing and engineering offshore oil and gas installations.
With these challenges in mind, Trelleborg looks at why next generation corrosion-free, rubber-based solutions can be a vital element to help ensure the protection of workers, structures and equipment.
Exceeding expectations
Although technology has advanced to better address the changing environment, customers still require superior, cost-effective solutions with an increased focus on longer life; increasing to up to 40 years from 20 years.
For optimum fire safety, choosing the most appropriate material is imperative. Choosing rubber-based materials is becoming a more popular choice within the offshore industry due to its naturally inherent flexibility and durability. Compared to alternative materials, such as steel, ceramic wool or fibreglass, rubber can withstand greater temperature extremes, weather conditions and vessel movements, while offering an exceptionally high durability. It is a diverse material that can perform at every level to damp, seal and protect, and most of all, it has an extremely long lifespan.
Safety for challenging environments
Onboard safety is a key priority for the offshore oil and gas industry but this is becoming progressively difficult in increasingly challenging environments as installation move further offshore.
Advanced fire protection systems are critical to ensuring onboard safety, whether it is the platform’s surface protection, an onboard deluge system or coating for the pipes and flanges, for example. The performance of these systems is essential for the safety of personnel, asset protection and preventing fire escalation.
So, in the offshore oil and gas sector, where the risk of uncontrolled, rapid fire spread is greater than most, firestop solutions need to provide full assurance to the onboard team that they will not fail to protect against fire. If damage is caused, costly shutdowns and repairs would be required and in the worst case scenario, the platform may fail all together.
The harsh offshore weather environment causes metal products and components to be susceptible to rust and corrosion, which is detrimental to the performance and function of the platform. Additionally, ceramic wool and similar materials used for fire protection will become less effective when wet. These less than optimal solutions are not an option when considering fire protection for an offshore facility.
Passive fire protection
Passive fire protection solutions are available in a series of materials and products to protect personnel, equipment, critical components and structures, and to assist emergency response activity by buying time to gain control of the fire, and evacuate the area. With proven engineering and manufacturing techniques for protection of all kind of fires, from simple cellulose to hydrocarbon and jet fire, the rubber materials are built-up of layers and meet corrosion, thermal, fire and mechanical protection requirements, protecting structures from exceeding temperature limits. Rubber has the unique capability of withstanding weather conditions, vessel movements, providing ease of inspection and fire protection over the life of a project.
It is key that any fire protection specified for use on an offshore facility provides the required fire protection throughout the fire exposure period. In addition, integrity means that protected areas between modules and decks will prevent the spread of flames and hot fumes throughout the fire exposure period.
For some projects, there can be the requirement for a protected surface area temperature not to exceed a certain level throughout the fire exposure period. For these types of requirements, insulation materials are used in conjunction with rubber fire protection. The critical temperature on the surface of a component is project specific information, with typical values to a maximum of +392°F to +752°F.
Similarly, in accordance with the Health and Safety Executive (HSE), the generation of smoke and non-toxic fumes must remain low.
Firestop applications
Laydown decks
The platform laydown deck areas are susceptible to regular impact and abrasion due to containers being loaded onto the platform, in addition to the harsh offshore elements. It must also protect against chemical and mechanical conditions and ensure that it does not give in to fatigue. This is all before fire protection is considered. A flexible decking material capable of withstanding these conditions is an ideal solution. Rubber provides the corrosion protection in addition to environmental and impact protection, all while maintaining the required fire protection rating.
By avoiding hot work onboard, fire hazards and shutdown requirements can be reduced. Surface protection designs that can be installed using other techniques should be prioritised. Surface tiling should feature insulation to isolate fire temperatures from areas below and should also ensure a non-slip surface for worker safety. Sophisticated coating designs can withstand blasts of up to 2.1 bars and jet/hydrocarbon fires for more than two hours.
The flexibility of a rubber-based tile means that it can take up movement in any direction, reducing the likelihood of cracking. Similarly, as it is regularly exposed to the sun, it should ensure UV and ozone protection so that it does not damage over time.
Flanges
Nuts and bolts used in flanges is another critical topside area that should be considered for fire resistance as they can be considered as one of the weakest areas of any platform or refinery. Typical fire protection that covers the complete flange does not allow for easy inspection of the units. Protecting only the nuts simplifies installation and facilitates regular inspection performance, leading to reduced installation times and overall weight. By using a molded rubber-based material on just the flange nuts this protects the stud bolts from elongating and the flange from breaking the seal during a fire.
Fire deluge systems
Another critical topside area to consider for fire resistance is the onboard deluge system. With a high number of ageing platforms and rigs currently in operation and the threat of critical failure looming, this is one area in particular where benefits from flexible fire protection will help ultimately reduce fire risks and potential downtime or closure.
By choosing a flexible, rubber based material, these deluge systems would be non-corroding and could withstand jet fires with a heat flux of 390kW/m2, temperatures above +2552°F making it an excellent material choice for use in deluge and sprinkler systems on offshore oil and gas installations and ships, as well as other hazardous environments.
Easing inspection for bolted connections
In refineries or wherever hydrocarbons are transported, pipes are flanged and held together with nuts and bolts. In case of fire, the flanges and pipes should maintain the same level of integrity to avoid escalation. Without the proper protection the nuts and bolts can elongate or deform when exposed to fire.
Traditional protection is to capsule the entire valve and flanges in a fire-insulated metal box - a bulky, heavy and expensive solution that creates challenges during inspection and maintenance. Inspection intervals can vary depending on the application, ranging in frequency from once a daily to monthly or yearly. The frequency is often mandated and regulated by independent authorities.
Inspection is a manual activity performed in the field, and poses several challenges. Imagine a refinery that has a hundred thousand bolts in hard-to-reach places that need to be inspected over a five year period. The current inspection process with a fire-insulated metal box is cumbersome and time consuming as the entire box has to be removed to inspect each bolted connection.
In addition, inspection and maintenance operations have to be performed by trained professionals, often in hazardous conditions, especially when dealing with the transportation of hydrocarbons. The amount of time and money spent on inspecting and reporting on critical applications globally is staggering.
With this in mind, companies are looking for a light weight, easy to install alternative to the fire-insulated metal box. One such solution is a rubber-based fire protection system that specifically protects just the nuts of a bolted connection. In stark contrast to the traditional bulky metal box, this lightweight solution is customisable to accommodate almost any bolt size, is easy to install and extends the service life of connections in the event of a fire as it is resistant to both jet fire and pool fire.
Conclusion
While deep-water drilling and production has been revolutionised by increasingly advanced technology in recent years, making high performance and dependable solutions has never been more important. This is because the requirement for equipment to operate safely and effectively while providing peace of mind, is becoming more challenging in these demanding and dangerous environments.
By installing effective and reliable passive fire protection systems onboard, the safety of hydrocarbons transportation installations will be increased. In the harsh offshore and onshore oil and gas industry, operators need the assurance of a material that delivers proven performance.
It is the responsibility of the manufacturer to ensure that they can provide high performance and reliable solutions, now more than ever. Similarly, operators should look to work with manufacturers who can provide the most advanced solutions which will guarantee performance and safety. Operators should have access to the latest and most innovative solutions that will significantly improve onboard safety and provide peace of mind to all those on board.
