In an effort to ensure uniform ship quality and construction standards around the world, there are currently two initiatives underway which seek to formulate a common suet of rules for the construction of the world’s most common ships, bulk carriers and tankers.
Common rules for bulk carriers have taken another step forward as the IACS Joint Bulker Project (JBP) team have made a series of presentations to shipowners, events meant to convey information as much as they are designed to seek industry input to the rules.
The JBP is a collaboration of the world’s leading classification socieites, and includes BV, CCS, ClassNK, GL, KR, RINA and RS. The aim of the Joint Bulker Project is to develop a set of common IACS rules and procedures to determine the scantlings of structural members of single or double hull bulk carriers of more than 295 ft. (90 m) in length. The first draft of those rules has now been presented to industry in Shanghai, Tokyo, Pusan, New York and Rome, and a review of the draft will be complete by October 2004.
The new rules are scheduled to enter into force with all IACS members on July 1, 2005.
Jean-François Segretain, regional Marine manager at Bureau Veritas
, is a member of the Steering Committee of JBP, and said "We have had excellent feedback from owners at all our consultation meetings, and after the meeting in London today we will be well placed to complete work on the rules. The shipping industry and IMO want to see class deliver a common high standard. These new rules are the first concrete evidence of the hard work and co-operation which IACS members have put into meeting those demands." The expected benefits of the new rules are:
1. To offer to the Industry a classification standard valid for both single hull and double hull vessels allowing fair comparison between these competing designs.
2. To eliminate competition between class societies with regard to structural requirements and design and construction standards.
3. To embrace the intentions of the anticipated IMO requirements for Goal-Based Standards for new buildings.
4. To ensure that a ship meeting these new standards will be recognized by the Industry as being safe, robust and fit for the purpose.
A number of innovative requirements will be included in the new rules:
1. For single hull vessels, more accurate formulas for the scantlings of the lower and upper frame brackets, explicit consideration for fatigue and new requirements for scantlings of connecting brackets and hatch end beams.
2. Adoption of net scantlings and values of corrosion additions based on 25 years conventional service life for all designs.
3. New sea loads formulas based on hydrodynamic computations and test model basin results.
4. Closed-form formulas for buckling, allowing complete and accurate determination of the scantlings of the secondary structure of the ship (plates and ordinary stiffeners) at an early stage of the approval process.
5. Explicit computation of the ultimate strength of the hull girder allowing a better assessment of deck and bottom structure in order to avoid breakage of the ship into two parts at sea or in port.
6. New fatigue procedure based on the combined previous experience of all members of the project.