seven years, and the average age of a merchant mariner with a Master's license being over the age of 50, there is a foreseeable problem in the near future." There is an industry-wide concern that this problem is already here. Without corrective action, the crew shortage predicted by Oberstar is all but certain. One likely industry indicator that this problem already exists is the increase in demand for designs that place a premium on crew comfort, primarily ambient noise reduction - evidence that operators are recognizing the importance of vessel habitability in attracting and retaining qualified crews. Again, the Diesel-Electric Propulsion System has provided part of the solution by allowing for the use of a much quieter drive method for the bow thrusters, which are generally located directly below the accommodations, as opposed to using a dedicated diesel engine or a hydraulically driven bow thruster, both of which are major sources of noise in the accommodations of a direct-drive OSV. Other methods to reduce noise consist of using noise abating materials, floating floors, and isolation of equipment and piping from vibration. Classification Societies have also followed this market driven trend with the addition of class notations (i.e. Comfort Class), which set standards for acceptable noise and vibration levels for different types of vessels and vessel compartments and provide different class notations based on the level of performthe support tube of the Rudderpropeller, is similar to the LSystem concept. Neither an abovewater gearbox nor a cardan shaft will be required, making the system extremely compact and easy for the shipyard to install in the vessel.
ance as measured against these standards. The introduction of the Integrated Diesel-Electric Propulsion System, combined with Dynamic Positioning (DP) systems, is undoubtedly the most prominent advancement of the new gen-
eration PSV designs. These systems allow for, first and foremost, crew member safety, as well as greater flexibility and efficiency. Since the total installed horsepower required in transit mode is not fully utilized while in DP mode, larger cargo transfer systems can be
installed to accommodate the increased cargo capacities and/or to reduce the vessels' offload time. Additional electric consumers can also be added to the design, such as additional thrusters or Fi-Fi pumps, without adding dedicated diesel engines to drive them, since the
"I trust ESAB for all my arc welding needs."
ESAB has set standards for flexible, reliable arc welding equipment since 1940. Whether you need equipment for MIG, Tig or Stick welding or a multi-process machine that lets you switch , easily from one mode to another, ESAB has the solution you need. Today s arc equipment line contains everything from small portable units to heavy-duty industrial equipment for harsh environments. ESAB offers: + Light- to heavy-duty industrial power sources + A complete line of MIG equipment for pulsed arc, short arc and spray arc processes + Genuine Heliarc� products for Tig and Stick welding multi-process packages + Wire feeders, guns, torches and accessories for any application Whatever your welding application, ESAB has the products you need and the quality you can trust.
GREAT THINGS HAPPEN WHEN YOU PUT US TO WORK esabna.com + 1.800.ESAB.123
April 2008
www.marinelink.com
27