Japanese-based ship classification society ClassNK has found that the minimum required brittle crack arrest toughness for extremely thick brittle crack arrest steel plates of 100mm used in ultra-large container ships is 8,000 newtons (N) / mm3/2.

In 2013, International Association of Classification Societies (IACS) had released its unified requirements on brittle crack arrest design for the use of extremely thick steel plates in a bid to improve the structural reliability of large container vessels.

Go deeper with GlobalData

Premium Insights

The gold standard of business intelligence.

Find out more

In its requirements, IACS has mentioned necessary measures to be taken to prevent brittle crack propagation in the event of occurrence of a crack.

The IACS requirements also noted that brittle crack arrest steel plates with a thickness of 80mm or less must have a brittle crack arrest toughness value (Kca) of 6,000N / mm3/2 or more at -10°C, which is the minimum design temperature for commercial vessels.

"The results of the tests have showed that brittle crack arrest steel plates with a thickness of 100mm must have a Kca of 8,000N / mm3/2 or more at -10°C."

However, no specific rules were given for cases where the thickness of brittle crack arrest steel is more than 80mm.

The required Kca value for brittle crack arrest steel plate with more than 80mm thickness is to be specifically agreed with each classification society.

How well do you really know your competitors?

Access the most comprehensive Company Profiles on the market, powered by GlobalData. Save hours of research. Gain competitive edge.

Company Profile – free sample

Thank you!

Your download email will arrive shortly

Not ready to buy yet? Download a free sample

We are confident about the unique quality of our Company Profiles. However, we want you to make the most beneficial decision for your business, so we offer a free sample that you can download by submitting the below form

By GlobalData
Visit our Privacy Policy for more information about our services, how we may use, process and share your personal data, including information of your rights in respect of your personal data and how you can unsubscribe from future marketing communications. Our services are intended for corporate subscribers and you warrant that the email address submitted is your corporate email address.

See Also:

ClassNK noted that verification tests were conducted by ultra-large-scale test specimens simulating the actual construction of the hatch side coaming and upper deck of ultra-large container ships under a joint R&D project.

The results of the tests have showed that brittle crack arrest steel plates with a thickness of 100mm must have a Kca of 8,000N / mm3/2 or more at -10°C.

ClassNK plans to reflect the new finding onto the IACS unified requirements in order to ensure easy use of extremely thick steel plates in the shipbuilding industry.

Last month, the society modified its rules and guidance for the survey and construction of steel ships in accordance with the new industry developments, such as amendments made to the international code for the construction and equipment of ships carrying liquefied gases in bulk (IGC Code).