Re - There is a plan of a Fire Tug from Richard Webb

Doesn't say in the ad if it's a particular design Peter, but it was built by Whangarei Shipyards.
32.4m powered by Ruston/Paxman english electric engines of 1007kw ea (1350hp) Auxilliary power is 2x 200hp Caterpillars. Starboard engine had a PTO for a fire pump originally, but has been decommissioned. Pic of Kupe with fire monitors originally. Was a Wellington Harbour tug, then sold to port Taranaki. Whangarei Ship Building made 2 the same (delivered 1971 and 1972)
They have built a number of tugs, ferries, landing barges and naval vessels etc over the years.

Kupe was replaced in 2018 by a Turkish built tractor (pic) Voith system pic is of Toia, the sister ship.
JB

The SA water tractors have also a very high superstructure. There is no room under the deck as the drive units take up a lot of space😊

Cornwall model boats have both the Voith Scheinder and Schottel (Azimuth Drives) at a Price!

Schottel drives 😊
Small Graupner 1761.
Still available via Bauer-Modelle
or Krick Models @ Cornwall Modelboats.com

LA Fireboat 2 Voith Schneider drives.

Still available via Bauer-Modelle.de

Yep OHSA

As you can see the maneuverability of the Voith Units it can turn the tug/ Water Tractor in it's own length!

The voiths are under those white plates at the back SA Harbours access to the voiths was from the deck otherwise the thrustplate would foul at Richards Bay which although the largest harbour in SA had some funny shallow spots being a natural harbour

Guys
SA Harbours had some of their water tractors fitted with fire fighting equipment. It made below decks extremely cramped and very noisy 90dB + especially with a couple of large turbo diesels running. I am sure the fire fighting equipment was an afterthought! Anything can happen in SA😊😊

There is a plan of a Fire Tug from Richard Webb that looks virtually identical to your NZ tug JB - Same very high superstructure , deck etc - except your NZ one has no fire monitors / hoses. Think its still available from Sarik

Here's a 1970 twin NZ built Voith tug (Kupe) for sale a while back, not too bad for room.

They are impressive but no room below decks with the Voith units all engine and drives😀😀

That is what i like about Tugs Jb, the manoeuvrability.
Great videos.

Martin555.

Great Videos JB - what i could not help thinking of is my friend with his 82ft tour boat maneuvering it around a rocky seal island off Hout Bay in the same manner as the tug facing the jetty - and that only using two props with standard rudders - always amazed by his skill - no bow thruster either.............

A couple of vids of Auckland tugs, one from the Orianas' final visit (2009) and a more recent one showing Voith tractors manouverability.

JB

Sorry Ian - bit misleading it was the old ferries that were condemned for not having enough watertight doors - although the hull was divided into 4 sections and could still float with 2 flooded. They had steerable Kort Nozzles as far as I know - were also pretty maneuverable.
Edited previous post for clarity

Seeing the in action when we were testing the Voiths on the SAH at Richards Bay they could stop on a sixpence. So I don't know where the safety issues were!

There was a member of SRCMBC who was also the Skipper of one of the Wight Link ferries . He built a model of his work one using the full size plans - used the Voith Schneider drives front and rear - they are slightly offset to one side - the model could spin about its own axis - apparently the large one can too - but he might have been in trouble for all the damage to cars it would likely cause..........

Don't like them as much as the old Ferries - but the Old Ferries were condemned from further use by elf & safeless new boaty rules - so although they were still fine - still worked well they were sold of to a 3rd world country and as far as Im aware are still going strong.........

Aint progress wonderful ...........

Hi Martin
That is a Kort Nozzle which turns with the prop inside it directs the water flow.
Fixed Kort Nozzles were originally used on tugs and riverboats and were fixed the idea being to stop erosion of the riverbank (so I am told)
You will see Fixed Korts with rudders and steerable Korts, my pusher tug which I must get started on has steerable Korts with a swing of about 70 Degrees.
It also increases the thrust
You will see a lot of them on tugs😊😊

Schottel is a Brand of Siemens Group although they market under Schottel.
Voith also manufacture Fluid drives couplings and rail drives Enormous Group.
You can see when a tug has Voith Schnieder Propulsion as the deck has two large circular plates that access the drives on deck

"Schottel ( Made by Siemens) ... Schottel is a trademark of Siemens
Voith Schnieder including principal of operation"

Really?😮 When did that happen Ian?
Has anyone told the CEOs of VSP (Voith Schneider Propeller) and Schottel GmbH?
Cheers, Doug 😎

"Schottel GmbH has its headquarters in Spay, two German subsidiaries in Hamburg and Wismar, and a network of subsidiary agencies in several countries and regions. "
https://www.schottel.de/marine-propulsion/

"Founded in 1867, Voith employs over 19,000 people today at locations in over 60 countries of the world. " Voith GmbH & Co. KGaA 2019
http://voith.com/us-en/drives-transmissions/voith-schneider-propeller-vsp.html

Here's some pictures on:-
Azimuth- Schottel ( Made by Siemens) 360deg Rotation sometimes using a Kort Nozzle Schottel is a trademark of Siemens
Voith Schnieder including principal of operation
I think you can buy both from Graupner Expensive!
Graupner used to make a model tug called Parat that took 2 x Voith Units
South African Harbour's had both but the Voith outmaneuvered the Schottel's and the Voith Equipped Water Tractors (Official Title) Tugs were at Richards Bay The bulk Coal Terminal Natal and Saldanha Iron Ore Port on the west coast due to the size of the bulk carriers. They have been moved around now😊😊
The Engines on the SA Harbours Tugs were WH Allen's of Bedford ( Now Gone)

Funnily Enough Designed from a dolphins Fin!

"Voith is extremely impressive."
And expensive - Cos it's very complex Ian, isn't it!
A rotating ring of vertical aerofoil sections with constantly varying 'angle of attack'😮
Very good for accurate station keeping for drilling rigs etc.
Cheers, Doug😎

Hi Ian,
I have spent some time on mine hunters with Voith units fitted.
Combined with Bow Thrust very manoeuvrable.

Martin555.

Azimuth and Voith Schneider are both drives that sit under the boat Mostly used for water tractors, Tugs and Deep sea Drilling as they can turn very quickly The Voith can turn on its own centre rotates 360 Deg and apply thrust and reverse in any direction . The Azimuth can rotate 360 as well but cannot turn on its own centre but can apply thrust and reverse in all directions. Extremely powerful Systems. Graupner make a Voith Schnieder Unit with copyright to Voith but Expensive! South Africa's Harbours have both systems but the Voith is extemely impressive.
Regards Ian
Ex Voith Schneider Agent

Sounds like they are for tight turns with power in confined spaces to me.

Hi Guys,

I have another question regarding these pods/thrusters.

I have seen somewhere on the net that some Tugs having two of these fitted at the back end and that they can be steered individually.
What are the advantages and disadvantages of this system ?.

Martin555.

Think most of the modern liners use the poddy things these days for manoooverability.
JB

MAYDAY MAYDAY I've just knocked my pods off!!😮😭
😎

There was an attempt to use these pods on some Great Lakes freighters some time ago. Problem was the lakes and rivers
have some really shallow spots. Hence there are any number of pods sitting on the bottom here. Oops!

Thank you very much for the information guys.

You are probably wondering why i asked this question, well, so am i LOL!!!

It is for a project that i am thinking about doing along side my U552.

Only thinking about.

Martin555.

Agree completely with Doug. Another interesting fact (courtesy of Wikipedia) is the apparent 'corkscrew' effect that has been shown to kill seals and probably porpoises.
Still like the reason they are used and are a great asset to limited size model props.
Andy

The one without the kort nozzle is an Azipod drive. Azipod® propulsion is a gearless steerable propulsion system where the electric drive motor is in a submerged pod outside the ship hull. Azipod® units can rotate 360 degrees to increase maneuverability and operating efficiency, with the proven ability to cut fuel consumption by up to 20 percent compared to traditional shaftline propulsion systems. Launched in 1990, Azipod® technology marked a new era in ship propulsion. Since then, ABB’s Azipod propulsion system has inspired naval architects to create more efficient and sustainable vessel designs.
Cheers Colin.

You're nearly there Bill👍
Correct Kort after Ludwig Kort.
The small gap between the prop tip and the ring reduces tip vortex effects.
At low speeds the ring (or nozzle) increases the prop efficiency and thrust.
They are also more efficient than open props when going astern and improve steering due to reduced side thrust effects on the hull.
Hence they are used on ships like tugs and trawlers up to 10 knots or so.
Above that the drag of the ring starts to become higher than the thrust increase.
They have no effect on power, only the engine can do that.😉
There are other versions , virtually with the ring fitted backwards (the ring has an aerofoil section)😮, that reduce cavitation and noise levels. So they are used mostly on warships.
Alles klar Herr Komissar?🤓😁
Cheers, Doug 😎

Hi Martin.
I an NO expert on this so may well be wrong, and if so stand corrected
I believe they are know as a Kort Nozzle.
The duct surrounding the prop creates greater control over the water passing thru the Nozzle.
It increases the efficiency and ratio of power provided by the prop.
I am sure there are many on this site who will know more than me on this one.
Regards
Bill👍