ABS grants Approval in Principle to Brevik Independent Tank Type-B gas containment system
Norwegian designer will use cylindrical tank concept for innovative small scale LNG carrier
(Houston) ABS, a leading provider of maritime shipping and offshore classification services, has granted Approval in Principle (AIP) to a new gas containment system concept designed in Norway by Brevik Technology.
The containment system uses a series of independent, cylindrical IMO Type-B tanks and for the AIP was designed for application in a gas carrier of 30,000 cbm.
In granting the AIP, ABS assessed the concept against the requirements of the International Gas Code, ABS Rules and the ABS Guide for Liquefied Gas Carriers with Independent Tanks. Since the tank design is a novel concept, a HAZID study was also performed.
“Once again, ABS is showing leadership in gas handling and transport, a field where we have half a century’s experience supporting innovation,” says ABS Chairman, President and CEO Christopher J. Wiernicki. “Designers are increasingly looking to extend the gas carrier concept into new trades, serving new markets and ABS Approval in Principle is a stepping stone in making this possible.”
The AIP marks the initial approval for the tank concept and could be followed by a general design approval upon completion of a vessel’s detailed design. Final approval would involve a vessel-specific shipbuilding project.
“ABS has completed more than a dozen assessments on new concepts in gas containment in recent years,” says Yung Shin, Head of the Containment System Group, ABS Corporate Technology. “Our focus during the AIP process was on assessing the system’s compliance with the intent of ABS Rules and other applicable standards, including strength of the tank, its support structure and its interaction with the hull.”
The tank design was created by Brevik Technology, a VARD affiliate company, with the intention of lowering the cost of construction for LNG and LPG carriers while providing a solution for the small-scale transport of gas.
“In creating the design, it was emphasized that no thermal induced forces were transferred from the ship to the tank and vice versa due to temperature variations,” says Øystein Kristoffersen Sæther, Managing Director, Vard Engineering Brevik. “The use of a cylindrical tank also means that the potential for damage from sloshing is low.”
Brevik is in discussions with shipowners and yards for a vessel design concept including the Type B tank, which it estimates could be between 15 to 20 percent less expensive to construct than a membrane containment system for a ship of this size.
ABS is a pioneer in the safe transport and handling of gas and has extensive experience with the full scope of gas-related assets. ABS classed the largest LNG carriers in service, including the world’s first LNG carrier, the Methane Pioneer, in 1959. In 2013 ABS formed the Global Gas Solutions Team in response to the rapid escalation in the number of gas-related projects, including LNG and LPG transportation and the growing use of LNG and LPG fuel.