Ice class tug gets warm bath for cold weather
The Neva escort tug being built by the Almaz Shipbuilding Company in St Petersburg is to be a universal emergency vessel for St Petersburg’s ecological services department. The Ice Class vessel will work in the Gulf of Finland on the Baltic Sea and is thus equipped with deck equipment of rugged construction.
Francisco Oliver of Spanish deck equipment manufacturer Fluidmecanica told MJ that the materials are of high grade steel, to survive to shocks at sub zero temperatures. It is a specification that the company is familiar with as Fluidmecanica has worked for Russia and northern countries for over 10 years. ‘We are used to minus 30ºC requirements’, added Mr Oliver.
The Novaya Zastava has a static bollard pull of 40 tons with a carbon steel towing winch and anchor windlass. A clutch arrangement connects or disconnects the chain lifters and towing drum from the main shaft and there is both a local and remote control. Shafts are on oil bath lubricated roller bearings and interestingly, the oil that lubricates the gears has two 220V 0.9 kW ‘warming’ resistors included in the design, which heat the oil inside the gearbox to give efficiency in cold weather.
The hydraulic drive for the towing winch comes from the two main engines through Kumera gears at 1,800 rpm and a back-up power pack for harbour operations.
The towing drum gives a pull of 400 kN in first gear, with a hoisting speed of up to 10m per minute. In third it gives a pull of 100 kN with a speed of around 40m per minute. The brake force is measured at around 600kN. The total drum capacity for 55mm wire rope 150m for two sections.
The anchor sections of the winch are on two sprockets, with a nominal pull at chain gear capacity of 28kN and a maximum pull of 42kN. The two lifters are made of cast steel and take 26mm chain. Each chain lifter has its own clutch and brake (both manually operated).
All the mechanisms are joined by a common bedplate. Shafts are on oil bath lubricated roller bearings and, as pointed out, there’s the warming system included to enable the gears work happily despite the Russian chill.
