Technology: New Nozzles Improve Northern Tug
Northern Transportation Company Ltd. of Hay River, Canada, recently completed a major refit of one of their quad screw pusher-towing tugs, the Edgar Kotokak. Vancouver's Robert Allan Ltd. provided design and engineering services for the refit which improved the operational efficiency of the tug. The refit included new CAT 3512B engines and replaced the open propellers and rudders with integrated Nautican Nozzles and Triple Rudders. Although total engine power increased from 4,500 to 5,640 hp on the Edgar Kotokak, and obviously bollard pull trials showed improvement, anecdotal evidence from the first month or so of operation seems to indicate that both the nozzles and Triple Rudders together with the new engines have improved the overall fuel efficiency.
Obituary: Josip Gruzling, Nozzle Expert, 1943-2007
Josip Gruzling, P.Eng., President of NautiCAN R&D Ltd., passed away Monday, September 10. Josip was a pioneer in the use of hydrofoils to increase the efficiency of tugs and barges. He used his inventiveness and determination to develop two types of devices: the High Efficiency Nozzles and Hydralift Skegs for barges, receiving nine patents for his efforts. Over 100 High Efficiency Nozzles have been built and over 40 Hydralift skegs have been installed worldwide. Josip got his start in 1968 working for Robert Allan Ltd., going on to found NautiCAN in 1972 to develop his ideas. Hydralift Skegs provide directional stability to barges with much less resistance than standard skegs, typically between a 35 to 50% improvement.
