9
SE 30/125S2 - SE 40/125S2
5408-2 - 2018
Master
5
Some boats is very fl at bottomed and has a very shallow draft in
the bow section. It might be very diffi cult not to say impossible to
fi t a tunnel thruster the usual way, at least as far forward in the
hull as a thruster should be (Fig. 1).
However, it is possible to install a tunnel thruster even when the
hull does not directly support the fi tting of a tunnel.
This is done by fi tting the tunnel halfway into and halfway under-
neath the exisiting hull and then strengthen it and smoothening
the waterfl ow by moulding a bulb around / underneath the tunnel.
This will allow installation in good position on the boat, maintaining
the reliability and space advantages of a tunnel thruster.
This can also be a good installation method for fl at bottomed
barges to avoid extremely long tunnels and huge oval tunnel
openings in the hull.
If the tunnel is over 250 cm long at its deepest point, it is recom-
mend that is is supported by a bulkhead as suggested in fi g. 2
and 3.
Tunnel installation in fl at bottomed hulls
EN
Tunnelinstallasjon i fl atbunnede skrog
NO
Noen båter har brede skrog som ikke stikker dypt i baugen.
Skrogtypen gjør det vanskelig å installere en thrustertunnel på
vanlig måte, spesielt med tanke på å plassere den langt nok frem
(Fig. 1).
Thrustertunneler kan allikevel installeres i de fl este båter. Dette
gjøres ved å la en del av tunnelen stikke ut i underkant av skro-
get. Tunnelen er sterk nok til dette, og thrusteren blir plassert lav
nok og langt nok fremme.
Dette gjøres ved at øvre halvdel av tunnelen støpes inn i skroget,
tunnelen styrkes i underkant ved å støpe en kul rundt tunnelen og
jevne den ut mest mulig.
Denne installasjonen kan også være gunstig for båter med fl ate
bunner, for å unngå ekstremt lange tunneler og store ovale tun-
nelåpninger.
Er tunnelen over 250 cm lang, anbefales at den støttes opp av et
skott som vist på fi g. 2 and 3.
C
D
Fig. 2
Fig. 3
16
SP 75 Ti / SP 95 Ti / SP 125 Ti
2.5.1- 2007
Segelboote weisen häufig einen Rumpf in Rennform auf, was
einen sehr flachen Rumpf im Bugbereich bedeutet. Es ist daher
schwierig oder fast unmöglich, den Tunnel an der gewünschten
(effektivsten) Stelle, also möglichst weit vorne im Bug zu plazieren
(Fig. 1).
Trotzdem ist es vielfach möglich unter diesen Bedingungen eine
Bugschraube einzubauen, auch wenn der Tunnel damit nicht völlig
vom ursprünglichen Rumpf umgeben ist.
Der Tunnel wird zur Hälfte in den bestehenden Rumpf integriert,
die andere Hälfte geht über diesen hinaus. Der Tunnel muß nur
noch verstärkt und strömungsgünstig abgerundet werden.
Dies erlaubt eine Installation in geeigneter Position bei Nutzung
der Zuverlässigkeits- und Platzvorteile einer Tunnelschraube.
Diese Installationsart wird von einigen der weltweit führenden
Segelboothersteller verwendet und führt meistens nur zu einem
äußerst geringen bzw. gar keinem Geschwindigkeitsverlust.
Diese Bauweise ist auch für Barkassen (z.B. Flußboote) mit
flachem Bug geeignet, um einen zu langen Tunnel und große
ovale Tunnelöffnungen im Rumpf zu vermeiden.
Installation in Segelbooten
D
Tunnel installation in sailboats
Fig. 1
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Many sailboats have a racing type hull which means that it is very
flat bottomed and has a very shallow draft in the bow section. It is
thereby very difficult not to say impossible to fit a tunnel thruster the
usual way, at least as far forward in the hull as a thruster should be
(Fig. 1).
However, it is possible to install a tunnel thruster in most sailboats,
even when the hull does not directly support the fitting of a tunnel.
This is done by fitting the tunnel halfway into and halfway under-
neath the existing hull and then strengthen it and smoothening the
water flow by moulding a bulb around / underneath the tunnel.
This will allow installation in good position on the boat, maintaining
the reliability and space advantages of a tunnel thruster.
This installation is being used by some of the world’s largest sailboat
builders, and has been proven to give little to no speed loss for
normal cruising.
This can also be a good installation method for flat bottomed barges
to avoid extremely long tunnels and huge oval tunnel openings in the
hull.
