hydraulic propulsion for tugboats??

Lurvio--if you ever get the time and feel up to it- can you PM me a diagram?

 

Hi Richard- i don't plan on any heavy tows astern. true very dangerous i agree! maybe the odd boat or light tow in calmer weather and probably my houseboat barge...but she's light...ill set up a "kentor shackle bridle"-run it off a towspan.
not expert -no- But I am an experienced Deckhand on tugs. cheers!

 

Thanks Gonzo!...electric drive was my first choice...btw-- any idea who might sell 20 hp ev 12- 72 volt motors? ive been looking all over but there hard to find...ive only come up wth golf cart motors to date..some forklift motors might work...I find lots of single engines but never two identical ones...there is always my caterpillar but it uses a lot of fuel. 2.5 gals an hour maybe more...

 

Hey Tugboat,

I posted a link for you over in BartKUs thread about a small passenger vessel (230') that uses a hydraulic motor attached to a paddlewheel.

EDIT:

This is probably the best description of her powerplant I've seen. look on page 12 for a description:

http://www.ntsb.gov/publictn/2009/MAR0904.pdf

 

Cthippo- much appreciated! Ive never seen that before...yikes--her engine room caught fire due to a hydraulic leak!! so this is certainly one drawback--its dangerous...!

 

Hey guys- ok something like this?
i have no idea what Hp it puts out--ill have to compare a diesel with similar torque i guess? so running my 20 inch props directly off the following setup?????

Hydraulic Orbit Motors direct connected to two props 20" x 24"
Price $209.99
SKU 8179574
Weight 11.6 pounds
Has a maximum speed of 585 RPM with 1,368 in lbs. of torque
CHAR-LYNN MOTORS offer high efficiency leak free performance over a wide range of applications including agriculture, forestry, mining, construction, and marine
Features:
Instantly reversible
1" shafts, 1/2" NPT ports
Max. continuous flow: 15 GPM (except for models with 2.8 cu. in./rev. displ., which are 12 GPM)
4-bolt
Model #: 101-3468
Displ.: 5.9 cu. in/rev.
Max. cont. pressure: 1,800 PSI
Max. speed: 585 RPM
Max. torque: 1,368 in-lb
Max. continuous flow: 15 GPM

then connected to this:
20 GPM 2-Position, 6-Way Selector Valve
Price $99.99
Discount -$30.00
Sale Price $69.99
SKU 8173932
Weight 5.2 pounds
20 gpm 2 position 6 way switch
Directs 2 incoming flows between 2 sets of outlet ports
Possible applications include individually controlling 2 double acting cylinders or hydraulic motors with one 4-way 3-position control valve
Max. continuous pressure: 5,000 PSI
Max. continuous flow: 20 GPM
Ports: #8 ORB

in turn connected to:
hydraulic gear pump
Price $169.99
SKU 8025184
Weight 10.7 pounds
Max. continuous flow: 20.39 GPM
Reversible-Useful for more than one application
3/4" shaft with keyway
CW rotation is reversible with minor changes to pump configuration (instructions included)
Pump has SAE A, 2-bolt flange
Cast iron end caps and steel gears with an aluminum gear housing
Max. cont. pressure: 2,610 PSI
Max. cont. flow: 20.39 GPM
Peak pressure: 3,330 PSI at 5% duty cycle
Speed: 250 RPM min., 3,000 RPM max.
Displacment: 1.57 cu. in./rev
Ports: #12 ORB inlet, #10 ORB outlet
Can be converted to a unidirectional motor with seal kit 8003893


the diesel which is then connected to the above pump???

is it this simple??

 

Now I understand, we have differing definitions of the word "simple".

-Tom

 

Hi Tugboat,
I'm new here, so have not covered all your project.
Two things for consideration might be, go to a motion control dealer and pick up a catalog by Browning or Eaton or anyone you can find, they are generally filled with engineering information that can give you all the technical info you need to get every part sized properly.

It sounds like your needs are close to the 30 HP range, if so, try to find a "Clarke Equipment Company" Bobcat skid stir loader. They started in 1984 or 1985 selling a 740 model that had a Kubota engine (diesel). If you can find one or two used machines for sell, you might have an entire package of engineered mechanical parts.

I get the impression you can dismantle and remount parts and pieces, this might be lots of work, but an entire power train at a very low investment.

Just a thought.

Ron

P.S. Reading another thread, I had a flash thought, instead of dismantling the machine, you could remove the lift boom and tires then weld or lock the machine in place and drive the twin screws of the boat from sprockets and chains mounted in place of the tires. Wow!! I can't believe I just typed that. I think the weight would be just over 2,000 pounds.
Guess I better go and do something else. )

 

They have subsequently switched to a non-combustable vegetable based fluid.

Still, something to consider.

 

not necessarliy--if this is very complex--i wouldnt do it..how i am understanding it is this: engine runs pump- which flows hydraulic fluid through hoses into a 2 spool directional control- the fluid then goes to the engines- then back to a reservoir. then through the pump again.

it is complex--but D.E. system is more so..i think..but the simplest would be simple diesel with single screw...

 

Ive been talking to the folks at princess auto--they recommeded vegetable oil...its non compressable too...Thanks!

 

http://www.frenchmarine.com/Product.aspx?PID=237&CID=21
This one is in Milwaukee http://www.ngcmarine.com/index2.html

 

Ron-Thanks for the response--i appreciate everyones inputs...you make a good point--for me though its easier to just go buy the parts--all of which can be bought off the shelf...this is a plus.
cheers thanks for the response!!

 

ok so now that im beginning to understan the way hydraulics work...the following is a quesion ive wondered about for some time-
if using either Electric or hydrualic drives--how hard would it be to simple use a chain drive to gear the props- i.e just run a chain form a sporcket on the hydraulic motor shaft to a prop shaft- using good pillow block bearings to secure the shaft??? Or a belt system?? either way it seems they could be direct reversed without issues...not as effiecient as a coupling but you can gear it higher if needed...??

 

You can make it work. There must be two thrust bearings on the drive shaft.