Search results
Results from the WOW.Com Content Network
Bollard pull is a conventional measure of the pulling (or towing) power of a watercraft.It is defined as the force (usually in tonnes-force or kilonewtons (kN)) exerted by a vessel under full power, on a shore-mounted bollard through a tow-line, commonly measured in a practical test (but sometimes simulated) under test conditions that include calm water, no tide, level trim, and sufficient ...
A ducted propeller, also known as a Kort nozzle, is a marine propeller fitted with a non-rotating nozzle. It is used to improve the efficiency of the propeller and is especially used on heavily loaded propellers or propellers with limited diameter. It was developed first by Luigi Stipa (1931) and later by Ludwig Kort (1934). The Kort nozzle is ...
The Voith Schneider propeller was originally a design for a hydro-electric turbine. [2] Its Austrian inventor, Ernst Schneider, had a chance meeting on a train with a manager at Voith's subsidiary St. Pölten works; this led to the turbine being investigated by Voith's engineers, who discovered that although it was no more efficient than other water turbines, Schneider's design worked well as ...
A tugboat is typically rated by its engine's power output and its overall bollard pull. The largest commercial harbour tugboats in the 2000s–2010s, used for towing container ships or similar, had around 60 to 65 short tons-force (530–580 kN) of bollard pull, which is described as 15 short tons-force (130 kN) above "normal" tugboats. [5] [6]
The reference load used in the design and testing of the towing winch is twice the static bollard pull. Even if AHTS-vessels are customized for anchor-handling and towing, they can also undertake, for example, ROV ( remotely operated underwater vehicle ) services, safety/rescue services, and supply duties between mainland and offshore ...
With a bollard pull of 200 tons and a speed of 20 knots (37 km/h; 23 mph), the Algerian ETVs are an improved version of the French Bourbon class. They are based in Oran and Skikda . By acquiring these three ships, Algeria became the leading Mediterranean nation in terms of marine salvage as of 2012.
Their kort-nozzle allows for a greater bollard pull however it loses its pull at anything over 10 knots (19 km/h; 12 mph) and loses speed in turns. [3] The Ville class are 13.71 m (45 ft 0 in) long with a beam of 4.72 m (15 ft 6 in) and a draught of 2.74 m (9 ft 0 in).
Magadan ' s bollard pull is 914 kilonewtons (93 tf) when operating with a continuous propulsion power of 7,000 kilowatts (9,400 hp). [11] However, for short-term operation the icebreaker can use its maximum shaft output of 9,100 kilowatts (12,200 hp) to generate a bollard pull of 1,400 kilonewtons (140 tf).