“We got 59,115 hours on those engines, without ever removing a head,” marvels Seaspan International’s Port Engineer Kevin Tweedy, “and they were still running so, at 5,000 to 5,500 hours per year, we could easily have done 60,000 hours.” But the company schedule worked to do a like-for-like repower. The pair of 850-hp, tier 1, Cummins KTA38 diesels were pulled out and a brand-new set of 850 hp, tier 2, KTA38s went in.

The Seaspan Cavalier was built in 1974, along with three sister ships. Three of the four 24-by-7.56-meter (82.8X24.8-foot) tugs are still working for Seaspan, who built the tugs in their own shipyard. The tug’s tow fuel and general cargo barges on the BC coast and can often be seen in front of a triple tow of wood-chip scows.  The tug is fitted with a single-drum Burrard Iron Works winch loaded with 548.6 meters (1800-feet) of wire rope. The tug is fitted with tow pins including a hold down claw.

Tweedy has a good many years at Seaspan and recalls that this is the tug’s third repower. “We cut a seven-by-eight-foot hole in the tug’s port side and installed both starboard and port engines through that,” he explained, adding that the same place is used each time with the old welds being cut in both the hull plate and framing. This ensures the structural integrity of the hull. Tweedy went on to explain, “Putting it back together we do a sealing weld from the inside first, then clean the weld from the outside before doing a second sealing weld from the outside.”

The new engines are coupled to the tug’s massive and virtually indestructible Lufkin RLS 3614 gears, with 6.987:1 reduction, turning three-blade 200.97-by-78.94-centimeter (79.125 S 70.45-inch) propellers in nozzles. “The props are in good shape,” says Tweedy, “but we will send them to Osborn Propellers for tune up, crack testing and pitch checks, as well as weld fill in way of cavitation, and balancing.”

The Seaspan Cavalier is expected to maintain its 27-tonne (60,000 pound) bollard pull after the repower. The transition from Tier 1 to Tier 2 will require some minor piping and electrical modifications. “We don’t expect any problems and the Cummins guys are good. They take care of us.,” confirmed Tweedy.

Photos of Seaspan Cavalier at work: Haig-Brown
 
Photos of Engines being fitted: Seaspan

For more information:

Kevin Tweedy
Port Engineer - Seaspan International
10 Pemberton Ave.
North Vancouver, BC
V7P 2R1
Mobile: 604 690 1714
Email:ktweedy@seaspan.com
 
 
Aaron Bruce
Marine Sales Manager - Cummins Sales and Service 
18452 96th Ave.
Surrey, BC
V4N 3P8
Cell: (604) 220-3765
Phone: (604) 882-5726