Kaplan 3B & 4B Propellers

Kaplan 3B & 4B Propellers

kaplan

The Austral Kaplan style propeller is the major part of a complete ducted propeller system. This specially designed propeller is mounted within a venturi shaped nozzle which for highly loaded applications can develop substantially greater thrust than open or free propellers.

Using this system the bollard pull (i.e. thrust) of trawlers and the like can increase by 25 to 35% while harbour tugs can typically increase 30 to 50% as compared to open propellers. In fact when a nozzle of correct geometric design is combined with an Austral Kaplan propeller, it can mean the same bollard pull could be achieved with a smaller engine providing substantial running cost savings.

Raked Kaplan 3B & 4B Propellers

kaplan-2-black

Conventional propellers have the blade face generation at 90 degrees to centre axis whereas the raked design has blades which are tilted at an angle to the centre axis. Austral now produces Kaplan propellers with aft rake, basically the centre of the blade at the tip is approximately in line with the rear face of the propeller hub. This aft rake design normally means a larger diameter propeller can be fitted because of greater aperture available toward rear of boat.

Design Features and Advantages:

  • Improved steering and manoeuvrability
  • Raked models available
  • Cast in Nibral and Manganese Bronze
  • Reduced vibration and noise
  • Individually pitchometer checked
  • Statically balanced
  • Bollard pull increased 25 to 50%
  • Substantial fuel savings

3 & 4 BLADE KAPLAN DESIGN DATA Disc Area Ratio 3B = 0.41 & 4B = 0.55


3B AQUA FOIL4B AQUA FOIL
Approximate Standard Hub SizesMaximum bore sizesMaximum Total Blade AreaMaximum
Total Blade Area
DiameterLarge Diameter
LengthStandard HubApprox.
Weight
Approx.
Weight
inchmminchmminchmminchmmSq inchSq cmin kg'sSq inchSq cmin kg's
24"6103.37"865.25 - 6.00"133 - 1522.00"50.8186119324248160029
26"6603.37"865.25 - 6.00"133 - 1522.00"50.8218140629292188337
28"7113.75"956.00 - 6.75"152 - 1712.25"57.1252162536338218045
30"7624.25"1086.50 - 7.50"165 - 1902.50"63.5290187041388250353
32"8134.62"1177.25 - 8.25"184 - 2102.75"69.9329212251442285163
34"8645.00"1277.50 - 9.00"190 - 2283.00"76.2372240060499322273
36"9145.33"1367.50 - 9.25"190 - 2353.25"82.5417269072560361385
38"9655.33"1367.50 - 9.25"190 - 2353.25"82.5465300084623402396
40"10166.00"1527.75 - 9.75"197 - 2483.75"95.25153324976904456110
42"10676.00"1527.75 - 9.75"197 - 2483.75"95.256836651037624918121
44"11186.50"1658.00-10.00"203 - 2544.00"101.662340221158365393142
46"11686.50"1658.00-10.00"203 - 2544.00"101.668143961359145897155
48"12197.12"1818.50-10.50"216 - 2674.25"108.074247871489946419171
50"12707.12"1818.50-10.50"216 - 2674.25"108.0805519416910796965203
52"13207.75"1978.75-10.75"222 - 2734.50"114.3870561818411677533231
54"13727.75"1978.75-10.75"222 - 2734.50"114.3939605820012598125257
56"14228.50"2169.25-11.50"235 - 2925.00"127.01009651522213548739288
58"14738.50"2169.25-11.50"235 - 2925.00"127.01083698924514539374322
60"15249.25"2359.50-11.75"241 - 2985.50"139.711597479260155410031355
62"15759.25"2359.50-11.75"241 - 2985.50"139.712377986281166010712377
64"162610.00"25410.00-13.00"254 - 3306.00"152.413198510316176911415408
66"167610.00"25410.00-13.00"254 - 3306.00"152.414029050352188112139451
68"172711.75"29812.00-15.00"305 - 3817.00"177.814899607398199712887510
70"177811.75"29812.00-15.00"305 - 3817.00"177.8157810181471211613654574
72"182911.75"29812.00-15.00"305 - 3817.00"177.8166910771578223914449648