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Coatings & Corrosion Control The Fate of the Iron: More Lessons From The Titanic Tragedy Tragedies in the maritime industry are often revered, particularly when a large loss of life occurs, as was the case when RMS Titanic sank on April 14, 1912. The industry is also noted for its ability to learn from mishaps, incorporating changes in design, procedures and oper- ations that are designed to avert future mishasps. Lessons learned and positive results occurring in the aftermath of Titanic are numerous and still growing, as a team exploring the formation of rusticles on Titanic's hull are drawing some interest- ing conclusions regarding the natural removal of iron from steel, and the potential compromise in safety and per- formance this may have, particularly on double-hulled vessels. The fascination with, and examination of Titanic has been thorough, to put it Baltic Spares Service Ltd. 8 Astronomow Street 80-299 Gdansk, Poland Phone:(+48 58) 554 55 86 Fax: (+48 58) 554 55 85 http: //www.bss.pl email: bss@bss.pl We are one of the biggest Polish suppliers of ship spare parts and equipment for vessels which are being built and repaired in Polish shipyards. We have long standing relations with all major producers of ship equipment in Poland. We can offer either from our own stock or directly from a producer of spare parts for main and auxiliary engines of Sulzer and Burmeister & Wain. We supply, among others, the following spare parts and complete ship equipment: -pumps of various types -compressors and turbochargers -electrical and electronic systems -hydraulic devices -centrifugal separators and filtrating devices -ship coolers, condensers and evaporators -cranes, ship lifts and winches -anchors and chains We run a bonded warehouse of valves and their spare parts produced by HOERBIGER - Vienna, thermometers from SIKA - Kaufungen and turbochargers with their spare parts from PBS - Velka Bites. Cooperation with us safeguards fast and high quality services indispensable for effective ship operation. Sound Specialty Coatings Corporation creating solutions for the next century www.sscoatings.com Anticorrosive Static Dissipative Nonskid DeckCoatings Sound Transmission Control Flexible Secondary Containment FDA,NSF Rated Coatings Non Toxic Hull Coating Solvent Free, low VOC Mil. Spec. Coatings Custom Coatings AQUAPLY M Prop*Coat 206-517-2611 TEL 206-463-7581 FAX Circle 210 on Reader Service Card mildly. Explorers have combed the sunken ship for reasons both scientific, historic and commercial ever since its final resting place was located. Forensic experts have pieced together many of the parts of the puzzle that caused the torn and broken ship to lie where she now rests. With that discovery 14 years ago, one feature that stood out in those first images of the ship was that the ship was festooned with rust-like growths, called rusticles, hanging down all over the hull and spreading out across the ocean floor in a slow moving rippling wave of growth. Regular visits to the site of the RMS Titanic reveal an ongoing deterio- ration coupled to larger masses of rusti- cles. Learning from the tragedy involves the forensic exercise and now the nature, form, function and conse- quences of the infestations of rusticles now coating much of the steel hull. Basic questions are: How long does the ship have left as a recognizable struc- ture? What are the rusticles? Where is the iron going? Why involve a microbi- ologist in the investigation? As a part of a team that has worked on water wells for three decades, one of the first observations is that the rusticles look very much like the iron bacterial growths often found down water wells. This was particularly true of iron cased water wells suffering from biological plugging. The technologies and experi- ences were transferred to the RMS Titanic site in the 1990's with the IMAX expedition followed by the 1996 and 1998 expeditions. Of particular concern was the rate at which the deterioration of the ship was occurring and what was the rusticles role in this event. In both 1996 and 1998, rusticles were recovered both directly from the hull and also from steel recovered from the site. Using images from these and other expedi- tions, it became very evident that the rusticles are growing faster, covering more of the steel, while at the same time, the ship's structures are beginning to collapse in a form of biological implosion. The questions therefore relate to what are the rusticles, why are they there, and where is the iron going? In 1996, a preliminary survey was made of the bow on the wreck site and the size and mass of the rusticles pro- jected. Subsequent analysis found the iron content ranged from 20 to 36 per- cent (average, 27 percent) with densities ranging from 1.2 to 1.8 (average, 1.4). All of the rusticles were very porous and retained 25 to 60 percent of the water when subjected to passive drainage. This was due to a sorptive capacity of 25 to 95 (average, 40) sq. m./g, a quarter, to a third of that of granulated activated carbon. Scanning electron microscopy performed by Dr. Henrietta Mann (Continued on page 66) Circle 311 on Reader Service Card Heavy highway vehicles backwards at 83 kilometres O iff . » ill per hour • v BM Incat ever forward at 45 knots. INCAT Europe Strandboulevarden 122, 5th Floor DK-2100 Copenhagen 0, Denmark Telephone: +45 3920 5075 Facsimile: +45 3920 6071 Website: www.incat.com.au INCAT Australia 18 Bender Drive, Hobart, Tasmania 7009 Australia Telephone: +61 3 6273 0677 Facsimile: +61 3 6273 0932 Email: incat@incat.com.au Circle 238 on Reader Service Card
