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and curing agents. This provision was challenged by the industry as being excessive and prohibitively expensive. A coalition among the National Shipbuilding Research Program Panel SP-3, the U.S. Shipbuilders Council, paint manu- facturers and the National Paint and Coatings Association met with EPA. After some discussion, the EPA relaxed that particular requirement. Other aspects of the recordkeeping requirements imposed on the shipyards are dis- cussed below. Impact of VOCs and HAPs on Shipyards Several shipyards were contact- ed regarding the impact of VOC/HAP rules. The yards have been anticipating, and preparing for, the new regulations for several years. The conversion to new, lower VOC formulations has affected the application properties of shipboard coatings. To reduce the VOC of epoxies, coating manufacturers use lower molecular weight resins in order to achieve the same degree of cross linking as the conventional (high solvent) epoxy. Pot life may need to be reduced. In some instances, a different mixing ratio may also be required (e.g., from 1:1 to 4:1). In order to achieve a VOC of 340 g/1 (2.8 lbs/gal), coating manufac- turers have used longer oil alkyds. This has generally resulted in longer dry times, hence, increased times to recoat and to put the unit into service. This puts additional pressure on already tight drydock and construction schedule and represents a hidden cost of VOC compliance. Application Methods Conventional airless equipment is considered capable of applying the current generation of VOC/HAP compliant coatings (e.g., VOC of 340 g/1 [2.8 lbs/gal]). However, if the VOC is reduced to significantly lower levels there may be a need for more specialized equipment. One example is plural component spray. Avondale Shipyards (New Orleans) has successfully utilized twin gun airless spray equipment. One limitation, however, is the need to maintain the pressure over long lengths of hose (100 ft. [30 m]). The yard found it necessary to transport the pump to the vicin- ity of the work pieces in situations where pressure losses were exces- sive. Twin gun airless also allows the applicator to preheat the mate- rial because the curing reaction does not begin until the material has been sprayed. This heating can significantly improve the application viscosity. None of the yards contacted has yet employed this technique in full production conditions. One shipyard experienced major problems in spraying new low VOC epoxy with conventional 40:1 ratio airless pumps. The manufac- turer was forced to change the for- mulation several times until the applicators could successfully apply the product with the existing equipment. Problems included sagging and fingering. Several yards have, however, used High Volume Low Pressure (HVLP) spraying. This technique provides a greater transfer effi- • AMFELS VALUE • RELIABLE SERVICE • QUALITY WORK • COST COMPETITIVENESS • AMFELS VALUE • // / OFFSHORE & PETROLEUM SPECIALISTS LUWM AMFELS Inc., located in the Port of Brownsville, Texas, has the proven marine and offshore construction and design capabilities to reliably complete any of todays sophisticated upgrade, repair and new construction projects to the rules of ABS, DNV, USCG, HSE, etc. AMFELS operates an ASME and API certified fabrication facility for efficiently building process packages for onshore and offshore production applications in addition to TLP's, SPAR's and other MOPU's (Mobile Offshore Production Units). A Leader In Servicing The Offshore Marine Industry AMFELS' new 48,000 ton drydock is capable of lifting the largest Jackup and Semisub- mersible Drilling Units. Access to AMFELS' modern 130 acre facility is by a 42 foot deep channel, with no height restrictions, from the Gulf of Mexico or the Intercoastal Waterway. AMFELS is fully equipped to offer quality service to the marine and offshore industries with large covered fabrication, blasting and machine shop facilities supported by land cranage up to 300 tons, and floating cranes of 700 tons & 150 tons. Houston Office: Texas Commerce Bank Building 5177 Richmond Avenue, Suite 1065 Houston, Texas 77056, USA Phone: 713/840-8811 Fax: 713/840-1198 U.S. Representative Keppel Marine Agencies Inc. Main Office: Port of Brownsville Highway 48 Brownsville, Texas 78523, USA Phone: 210/831-8220 Fax: 210/831-6220 • 3MVA S13JWV • SS3N3Allil3dWO} ISO) • MHOM AlllVDO • 331 Ad IS 319VI132I • 3(11 VA S13JWV • June, 1998 Circle 315 on Reader Service Card 61