Μήνυμα για τους χρήστες φορητού αναγνώστη

Καλώς ορίσατε, Εάν χρησιμοποιείτε πρόγραμμα φορητού ανάγνωστη σας συνιστούμε να μεταβείτε σε "Λειτουργία πλήρους πρόσβασης".Αυτή η λειτουργία έχει σχεδιαστεί για να βοηθήσει διαφορετικους τύπους πλοήγησης:


Μετάβαση στο κύριο περιεχόμενο


Επιλογές Προσβασιμότητας

Μέγεθος γραμματοσειράς:

Πλάτος διάταξης:

062elli
co

Eliche Radice was founded at the beginning of the last century (in 1919) and the company is still owned today by the Radice family. The company structure in Italy is developed over 50,000 m², of which 15,000 m² is covered, and is made up of around 85 employees. The range of products which Eliche Radice is able to provide includes not only the propellers, but also the different components of the whole propulsion system starting from the gearbox coupling flange to the rudder. Traction or propulsive FPP, for manoeuvring systems, blades and hubs for CCP propellers, propeller shafts and relative brackets, seals, fixed or directional nozzles, hydro lubricated bearings and rudders.

For the monoblock propellers the maximum diameter is 4 metres or 4 tons of weight, while for the propeller shafts the maximum length is 12 meters with 250 mms diameter. Standard products are normally available from stock while others are exclusively planned according to the customer’s specifications.

Nozzle is a type of propulsion system suitable to working vessels (tow-boats, fishing boats, river barges and pusher tugs) in the sea and rivers.

The nozzles can be of two types: “Fixed” or “Rotating” (Steering Nozzles).

The main geometric parameters are the following:

  • L/D ratio D = Internal diameter of the nozzles, where the propeller is positioned L = Nozzle length
  • Contraction ratio This is the ratio between the point of water entry at the aft and the exit point at the stern
  • Section geometry

  • The advantages gained are the following:

    • Reduction of propeller diameter;
    • Reduction of propeller shaft and stern tube diameter;
    • Reduction in vibrations, especially in the wider stern as the nozzle regulates the water flow; 
    • Reduction in ship’s pitching when in rough waters; 
    • Increase in the propeller thrust to the tow and to the Bollard-Pull; 
    • Possible increase of ship speed by approx. 15%; 
    • Better performance from heavily loaded propellers, especially in shallow water; 
    • At the same conditions of speed, trawler work, Bollard-Pull, need 30% less power engine; 
    • The smaller engine cost, the reduction of fuel consumption and the high-performance of transmission, allow recovering the investment within one or two years.
  • Nozzle type 19A is most commonly used. However, when there are particular applications, or a special request, it is possible to prepare other nozzles as indicated below.

    The nozzles are divided into different styles, with considerably different characteristics and uses:

    • Nozzle 19A. This nozzle is suitable for very heavily loaded propellers and when excellent manoeuvrability is needed. When in forward gear it has an improved performance of 2-3% when compared to all the other nozzle types. L/D = 0,5
    • Nozzles 22 and 24. These nozzles are used in circumstances where the Bollard-Pull value is of high importance (Tow-boats). L/D = 0,8 (Nozzle K22), L/D = 1 (Nozzle K24) These two nozzles have identical Naca sections but are allocated different lengths “L”. 
    • Nozzle 37. This nozzle has a symmetric shape. It is used in circumstances when a strong Bollard-Pull is necessary in both forward and reverse gears. In reverse gear, the performance is some 7-10% greater than the traditional K19A model. L/D = 0,5

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