Different commercially available materials (e.g., Marlow™, Stainless Steel) are often used to fabricate basic or complex tubing to address specific performance requirements. Specifically, maritime applications, such as offshore platforms, drilling rigs, and subsea apparatus, are often exposed to corrosive marine atmospheres (e.g., seawater), direct contact with marine organisms like barnacles, or extreme temperatures (−40–80 °C). Consequently, these conditions require using materials that resist damage from organic acids, water, UV radiation, or other adverse environmental factors.
Extreme Maritime Conditions
The prevailing wind speed (Wmax) in offshore applications can be 100–200 mph for a typical deep-water installation. The mechanical loading of wind loads, combined with high temperatures and corrosive environments, poses significant challenges in using conventional fittings.
The wave height (Hmax) in offshore applications is typically between 6–8 m for a typical deep water installation. The mechanical racking and slamming loads of wind, combined with high temperatures and corrosive environments, pose significant challenges in using conventional fittings.
Storm conditions (e.g., storm surges) can be experienced during construction, in mature installations due to extreme weather events, or as part of a cyclone.
Consequences may include uplift forces (e.g., slamming forces), high wave energy (e.g., breaking forces), and the entrapment of high winds and waves in pipeline systems and structures.
The presence of ice in the offshore environment can result in structural loading from the weight and movement of ice (e.g., bending, torsion, lateral banging). Glacial ice can also produce impact forces when it is carried by high winds and waves, resulting in a glancing blow on the structure. This could damage structures (i.e., jacket legs) and cause severe damage to pipelines and platform decks.
Rust and Corrosion
The presence of rust and corrosion in the offshore environment can result from the localization of water, contaminants, mud, and biofouling. Corrosion is a major risk to offshore operations due to the harshness of the environment (e.g., higher moisture contents) and organic acids (e.g., hydrocarbons). Corrosion can be increased by abnormally high temperatures or exposure to other metals that are galvanic.
Reliable, Durable, Robust Tubing Materials Solutions for Overcoming Maritime Conditions
When addressing the unique challenges posed by extreme maritime conditions, selecting the right tubing materials becomes critical in ensuring offshore projects’ success and longevity. World Wide Metric offers a range of advanced tubing solutions designed to withstand the harshest environments, from corrosive marine atmospheres to extreme temperatures. Let’s delve into some of the most reliable and durable tubing materials that can conquer these maritime challenges.
In the 1960s, a groundbreaking family of alloys entered the oil and gas markets, revolutionizing the offshore industry. Copper-nickel alloys, such as A182, ATS1, and BSCC-A234CB, quickly became one of the go-to materials for offshore gas pipelines. These alloys, known for their corrosion resistance and durability, are easily fabricated using conventional pipe processing techniques. They exhibit exceptional resistance to high temperatures and marine pollutants, including chlorides, sulfides, and molybdenum. As a result, copper-nickel alloys offer a reliable solution for combating the harsh effects of corrosive marine environments.
Stainless steel has emerged as a stalwart choice for offshore applications over the last half-century. Its durability and reliability make it a popular material for various offshore components. Alloy A36, in particular, boasts a higher strength-to-weight ratio than traditional steels. This attribute is invaluable in fabricating components that require wear and tear resistance in marine atmospheres, such as fitting heads. The proven track record of stainless steel in offshore applications underscores its ability to withstand the rigors of the sea.
Commercially available carbon steel is a common choice for pipelaying and production platforms due to its affordability and superior rust resistance. It finds its way into the fabrication of both basic and complex fittings.
However, despite its toughness, carbon steel’s susceptibility to various corrosion issues, notably galvanic corrosion, renders it unsuitable for offshore applications. While it offers advantages in certain contexts, extreme maritime conditions necessitate materials with enhanced corrosion resistance.
Steel w/ Epoxy Coating
Addressing the challenge of rust and corrosion in marine environments, epoxy coatings present a cost-effective solution for protecting steel pipelines. The standard thermal cured epoxy-based coating, such as WKL or HJP, requires elevated temperatures during application. This coating is typically applied after pipeline erection and can be added at any point during operation, including repairs. Epoxy coatings effectively shield pipelines from the detrimental effects of marine elements, prolonging their lifespan and ensuring optimal performance.
Galvanized Carbon Steel
Galvanized carbon steel offers another cost-effective approach to combat rust and corrosion in marine environments. The coating is electrically welded onto the pipe’s surface and can be applied during operation or repair. This method provides a protective barrier against corrosive forces, contributing to the overall durability of the pipeline in offshore conditions.