Page 14: of Marine News Magazine (March 2013)

TECH FILEAdvances in Bollard Pull Testing Technology By Joseph KeefeMany arguments about the capabilities of a tug can be quickly settled when you can conduct a full-ahead power, bollard pull test. ?Many captains will argue about horse- power, hull design, rudder angles, and other variables, but the only thing that really matters is bollard pull and a test provides empirical data of pure power,? says Mark Babcock, VP of Machinery for Sause Brothers? 200 tugs, barges and OSVs. ?A well maintained vessel shouldn?t lose bollard pull over time, but with every propulsion related change, engine overhaul, shaft or propeller retro t, the ves- sel should be re-tested.? While the bollard pull test has been around for many de- cades, recent changes in technique, technology and data- logging allow engineering and operations to  ne tune the analysis and provide more accurate information. Provid- ing accurate reports allows pilots, agents and customers to have con dence in towing and tug capabilities at the edge of the performance envelope. While many new tugs are built larger and more powerful than ever before, most of the tugs on rivers and ports have years on their engines and the ability to move their tow when it ultimately matters, should be tested against expectations.MTNW Tension Link 14 MNMarch 2013 MN March2013 Layout 1-17.indd 14MN March2013 Layout 1-17.indd 143/5/2013 10:28:00 AM3/5/2013 10:28:00 AM