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Marine Materials Aluminum Gone "Bad" By John W. Waterhouse, P.E., President, Elliott Bay Design Group There has been a lot of discussion in the marine industry over the past year with regard to "bad" aluminum. To briefly recap, a number of boat builders purchased aluminum from a supplier that met the requirements of ASTM 5083 H321. This alloy is accepted by both Lloyds Register (Lloyds) and Det Norske Veritas (DNV) for building alu- minum vessels. After the aluminum was used to construct some vessels, the oper- ators began to observe surface pitting corrosion. Upon investigation, it was discovered that the purchased plate had been treated differently during manufac- turing, with the result that manganese nodules were precipitating out of the alloy, thus making it susceptible to inter- granular corrosion. The result was that newly-built vessels had to be rebuilt and their original hulls scrapped. Owners weren't able to use their new boats, ship- yards incurred costs to investigate and rebuild, and the aluminum distributor and provider are faced with claims. Not good all around. In response to the investigation, the ASTM International Committee B07 and the Aluminum Association have been meeting with the U.S. Coast Guard and industry members to review and improve the relevant standards. Classification societies such as Lloyds, DNV, and ABS are also involved in the discussions. Beyond testing for chemi- cal composition and mechanical proper- ties, the standard will likely be expand- ed to include corrosion tests. Plates that have been tested and passed as suitable for marine use will also be marked clear- ly to prevent inadvertent mixing with non-marine aluminum. All of these measures should prevent a repeat appearance of unsuitable aluminum in high speed ferries and workboats. As a designer of vessels, I am con- cerned that there is a more significant challenge that hasn't been addressed — namely the increasing use of third party standards in the marine industry. As vessels become more complex and more international in their design and con- struction, there is ample opportunity for misapplication of standards. Yet, there are increasing pressures on regulatory bodies such as the U.S. Coast Guard to use third party standards. For example, years ago the U.S. Coast Guard had developed a fire testing standard for marine interior materials. The problem for the industry was that this standard was different from the more common fire testing standards, thus forcing man- ufacturers to conduct expensive tests if they wanted to implement their products into the marine industry. The problem for the U.S. Coast Guard was to keep up with changes in materials and testing procedures so their standard did not become obsolete. Hence, as part of the rewrite of the Guide to Structural Fire Protection, NVIC 9-97, the U.S. Coast Guard now accepts Universal Laboratories, ASTM, and IMO stan- dards for construction and testing of fire doors. Industry benefits by having more choice, manufacturers benefit by fewer tests, and the U.S. Coast Guard benefits by having others take on the burden of writing and updating standards. I have been involved with several stan- dards development committees, the ABS Americas Small Vessel Committee, NFPA 1925 - Marine Firefighting Vessels, and the Passenger Vessel Access Advisory Committee. It is both an enriching and a humbling process. Enriching because you learn details about the subjects that you could never learn elsewhere. Humbling because standards often reflect compromises between strong opinions. Therein lies my concern about third party standards. We often invoke them without really understanding what the standards say or, as in the case of the aluminum alloy specification, what they don't say (i.e. no corrosion test). Often there is no record of how the standard was chosen since committee discussions are seldom recorded. For example, the ADA minimum standard width for door- ways is 32 in. Most people mistakenly associate that standard with wheelchairs. Actually, the width was chosen because it is the minimum practical width for persons with crutches to readily pass through the doorway. Designers, builders, and operators are dealing with an ever increasing number of standards. The alphabet soup of ASTM, ANSI, ICS, ABYC, IEEE, NFPA, ISO, IEC, etc. is confusing. Obtaining copies of all of the relevant documents is aboth expensive and ongo- ing as the standards are revised. Reading the standards takes time and lots of caffeine to stay awake. The nat- ural tendency is to assume that the code writers knew what they were doing so "use the standards and don't waste time on researching the details." I don't have a solution to this chal- lenge. I certainly encourage industry members to get involved by working on a standards committee. As an industry, we shouldn't rely upon others to make decisions that will affect our future. We also need to share our discoveries with others so we are all smarter. Just think about crutches the next time you pass through a doorway...and read the fine print when you order aluminum. Dupont Surfaces - Corian Zodiaq DuPont showcased its Corian Bas-Relief signa- ture surfaces, a proprietary new technology that allows the material to be textured in an endless array of designs, at this year's Sea Trade Cruise Shipping Convention in Miami, Fla. Corian Bas-Relief signature surfaces can be used in a myriad of vertical applications including wall cladding, furni- ture, ceilings, room partitions, sign- boards, elevator inte- riors, border trims, waterfalls, merchandising displays, retail fixtures and transaction counter fronts. DuPont offers a range of stock textures, includ- ing Bubbles, Waves, Rapids and Pillows. Circle 36 on Reader Service Card E Paint Company, Inc. E Paint Company recently received approval for the commercial sale of its E Paint SN-1. This same paint type has also been chosen by the U.S. Coast Guard for use on its aluminum ves- 44 sels. The company's product base also includes E Paint Z0, a single component, ablative antifoul- ing paint formulated for commercial use, and EP2000, which is a high performance antifouling paint that yields a hard racing finish. Circle 175 on Reader Service Card Honeywell Honeywell's high performance polyester fiber will be used for the first permanent synthetic mooring system in the Gulf of Mexico. Known as the 'Mad Dog' truss Spar, the installation, which is to occur this fall, will also signify the first use of polyester ropes for a Spar-based floating pro- duction system. Mad Dog will be moored in 4,420 ft. of deep water with an 11-line taut leg system in the U.S. Gulf's deep-water Green Canyon Block 826. Ropes involved will have a design minimum spliced breaking strength of 4,260 kips (1,932 tons); as per their manufac- turer — Marlowe Ropes of the U.K. Circle 39 on Reader Service Card Honeywell Sensotec Sensotec's new Flush Diaphragm Model 355 pressure transducer is a rugged, one piece, stainless steel unit, which features a flush diaphragm design, making it ideal for operations that involve the spraying or application of sealants, paints, coatings or other congealable media which can clog conventional pressure ports. The internally amplified Model 355 deliv- ers a high level 4-20 mA or 0-5 VDC output, ready for PLC or instrument interfacing. Circle 70 on Reader Service Card IMIXA^'PANEl KSSS? V f < .?4 INEXA Panel INEXA Panel's TNF modular system has been providing a jfo competitive benchmark for wall panel systems for the past 20 years. The TNF sys- tem ensures that all accom- modation components are produced with pre-set dimensions — tailored into a modular concept. Available in two sepa- rate modules, 50 mm and 100 mm, the system has been developed throughout two decades — in close cooperation with leading shipyards. The system also provides quick installation, is cost- effective and is relatively easy to maintain. Circle 41 on Reader Service Card Jamestown Metal Marine Sales Since 1962, Jamestown Metal Marine has been provid- ing and installing interior accommodations for the marine industry. Based in Boca Raton, Fla., the compa- ny provides a full selection of services including design, material supply, manufacturing and installation for all types of vessels. Jamestown Metal Marine is also part of a corporate network that includes Jamestown Foreign Sales Corporation with vast knowledge and experience in the worldwide marketplace. Providing estimating and design development, planning and scheduling, and engi- neering and design integrations with approvals by regulatory bodies, Jamestown operates as exclusive agents and supplier systems for joiner systems and materials. Circle 40 on Reader Service Card Kalb Corporation In a continuing effort to improve the quality of Maritime Reporter & Engineering News
