Balancing a 24m 26ton Dutch Barge

[LeonR]

Hey,

 

Very new to all of this and just wondering what my allowance is for how much weight I cn put on one side of the boat before it starts to tilt?

 

I have removed 2 x 1000ltr tanks from the stern. I don't need that much and want to put around 1000ltr total in the bow. I was thinking 2 x 500ltr tanks. 

 

I've heard people mention a ballast tanks. Is that soemthing I could need or is 500ltrs not that  much for the size of the boat.

 

Thank you in advance, this forum has been very good t me so far.

 

Thanks

[MtB]

"Balancing a 24m 26ton Dutch Barge"

 

Forgive me but surely a 24m DB weighs one helluvalot more than 26 tons.

 

Maybe you have a dutch barge-style narrowboat? 

 

 

 

[Paul C]

It would depend where the metacentric height is, which is a function of the centre of gravity and the centre of buoyancy. Which are a function of hull shape and all the items/location of items on a boat. Don't forget free surface effect for larg(er) tanks too.

[magnetman]

22 minutes ago, MtB said:

"Balancing a 24m 26ton Dutch Barge"

 

Forgive me but surely a 24m DB weighs one helluvalot more than 26 tons.

 

Maybe you have a dutch barge-style narrowboat? 

 

 

 

yes it will be a lot heavier. 

 

My 17.5m x 3.6m English barge was 29 tons and not very deep at all. 

 

I would think a 24m Dutchy which will be about 4.3m wide would be more like 40 ton or more. 

[ditchcrawler]

40 minutes ago, MtB said:

"Balancing a 24m 26ton Dutch Barge"

 

Forgive me but surely a 24m DB weighs one helluvalot more than 26 tons.

 

Maybe you have a dutch barge-style narrowboat? 

 

 

 

In another post the OP discussed insulating the curved bow, so I think it is a barge 

[GUMPY]

Parglena is 18.2m and 35ton, the fuel tank was in the curve if the stern, the difference between a full and empty 850 litre tank was a change in freeboard at the stern of about 50mn. 

Adding a 500litre water tank on one side  meant shifting a few bits of ballast to cancel it out.

When we extended from 15m  to 18.2m it required 5 ton of ballast  to get the boat back down in the water.

What I am trying to say is that  moving a few tanks around is not going to make much difference in a boat that size.

Personally I would leave the tanks in the stern and just add the tanks at the bow then if needed you can use the tanks to balance from front to rear.

[LeonR]

11 hours ago, MtB said:

"Balancing a 24m 26ton Dutch Barge"

 

Forgive me but surely a 24m DB weighs one helluvalot more than 26 tons.

 

Maybe you have a dutch barge-style narrowboat? 

 

 

 

Our paperwork definitely says that it weighs 26 tons... Sounds like I should query this. 

50 minutes ago, GUMPY said:

Parglena is 18.2m and 35ton, the fuel tank was in the curve if the stern, the difference between a full and empty 850 litre tank was a change in freeboard at the stern of about 50mn. 

Adding a 500litre water tank on one side  meant shifting a few bits of ballast to cancel it out.

When we extended from 15m  to 18.2m it required 5 ton of ballast  to get the boat back down in the water.

What I am trying to say is that  moving a few tanks around is not going to make much difference in a boat that size.

Personally I would leave the tanks in the stern and just add the tanks at the bow then if needed you can use the tanks to balance from front to rear.

So, you don't think there would be any issue with one tank being full and the other empty, for example? Or should they fill evenly and empty evenly? Actually now I have said that out loud that makes sense!

11 hours ago, Paul C said:

It would depend where the metacentric height is, which is a function of the centre of gravity and the centre of buoyancy. Which are a function of hull shape and all the items/location of items on a boat. Don't forget free surface effect for larg(er) tanks too.

Going to research all the bits I don't understand here. Every day is a school day! 

10 hours ago, ditchcrawler said:

In another post the OP discussed insulating the curved bow, so I think it is a barge 

Yep!

[MtB]

44 minutes ago, LeonR said:

Our paperwork definitely says that it weighs 26 tons... Sounds like I should query this. 

 

My guess is this is perhaps the weight of your steelwork, prior to launching and ballasting.

 

 

[Ronaldo47]

By applying Archimedes' principle, if you multiply the area of the submerged part of your boat (assuming it has straight sides and is level) by the depth of immersion, that will approximately give the volume of water displaced. The weight of that volume of water will equal the weight of your vessel.  

Edited December 13, 2023 by Ronaldo47
typos

[GUMPY]

Somebody produced a very good calculator for displacement taking into account the swims etc. it might have been @Albion but I can't remember

Edited December 13, 2023 by GUMPY

[blackrose]

15 hours ago, magnetman said:

My 17.5m x 3.6m English barge was 29 tons and not very deep at all. 

 

My English widebeam is of the same dimensions and the same weight.

3 hours ago, MtB said:

 

My guess is this is perhaps the weight of your steelwork, prior to launching and ballasting.

 

 

 

Or perhaps it's made of wafer thin steel! 😯

[Tracy D'arth]

Was it "ballasting" that you were enquiring about? 

[ditchcrawler]

I am sure if you posted a photo of your boat you would get lots more useful information, at the moment people are guessing at whats happening and what the problems may be

[LeonR]

On 12/12/2023 at 22:31, ditchcrawler said:

In another post the OP discussed insulating the curved bow, so I think it is a barge 

Yep!

[Alan de Enfield]

7 minutes ago, LeonR said:

Yep!

 

I reckon your weight is probably 'out' by 50%

 

Don't order a crane to lift a 26 ton boat, it will be expensive and you are unlikely to get lifted.

 

The 'size' (weight lifting capacity) of the crane also depends on the distance of lift (from the centre of the crane).

We had a 100 tonne crane and the boat weighed 11 tonnes, it lifted OK but when the boom was extended to put us down to out placce 'on the hard' the overload alarm went off.

 

You need to get a good estimate of the weight or this could happen to you .................................

 

 

 

 

 

 

[ditchcrawler]

34 minutes ago, LeonR said:

Yep!

Now IF I was going to live on a boat something like that would fit the bill nicely

 

[LeonR]

20 hours ago, Alan de Enfield said:

 

I reckon your weight is probably 'out' by 50%

 

Don't order a crane to lift a 26 ton boat, it will be expensive and you are unlikely to get lifted.

 

The 'size' (weight lifting capacity) of the crane also depends on the distance of lift (from the centre of the crane).

We had a 100 tonne crane and the boat weighed 11 tonnes, it lifted OK but when the boom was extended to put us down to out placce 'on the hard' the overload alarm went off.

 

You need to get a good estimate of the weight or this could happen to you .................................

 

 

 

 

 

 

 

Woh. Where's the boat at this point??

19 hours ago, ditchcrawler said:

Now IF I was going to live on a boat something like that would fit the bill nicely

 

Chuffed aint the word. Excited to learn about boats almost as much as I am excited to not have a mortgage! 

[magnetman]

The crane fell in while being driven along a towpath. 

 

Clue is the hook position - not in use. 

 

Presume the driver followed his training and got out fast. 

 

https://www.wharfedaleobserver.co.uk/news/10214361.driver-leaps-to-safety-in-apperley-bridge-canal-crane-plunge/

Edited December 15, 2023 by magnetman
inaccuracy

[Paul C]

27 minutes ago, magnetman said:

The crane fell in while being driven along a towpath. 

 

Clue is the hook position - not in use. 

 

Presume the driver followed his training and got out fast. 

 

https://www.wharfedaleobserver.co.uk/news/10214361.driver-leaps-to-safety-in-apperley-bridge-canal-crane-plunge/

 

I guess AI isn't that sophisticated - it saw a crane in the water and made an assumption. I remember that incident - the bank gave way, unsurprisingly. You can see it in the pic.

[Alan de Enfield]

Maybe you'd prefer this one ?

 

 

[GUMPY]

Loads of falling cranes and boats  HERE

 

 

[Paul C]

7 minutes ago, Alan de Enfield said:

Maybe you'd prefer this one ?

 

 

 

That seems to have happened in Russia. Of course, a Russian kg is the same as an English kg, so it could occur in the UK, but I believe the approach to safety and in particular, ensuring overload situations like this don't happen in the UK, is somewhat different. I can't remember seeing a UK crane which DOESN'T have an overload warning alarm, and I've never seen a crane which doesn't have a plate/diagram showing the working safe load limit at various angles and extension of the boom.

[cuthound]

I had to use a 1,000 tonne crane to lift a 40 tonne generator and place it on the roof of a 14 storey building in London's Docklands.

[IanD]

14 minutes ago, cuthound said:

I had to use a 1,000 tonne crane to lift a 40 tonne generator and place it on the roof of a 14 storey building in London's Docklands.

Ooh, proper big boys toys! 🙂

[cuthound]

33 minutes ago, IanD said:

Ooh, proper big boys toys! 🙂

 

I just watched from a safe distance. 😂

 

That job was jinxed. Twice the lift had to be terminated because of hydraulic leaks and then we had to wait several days for the high winds to drop. I spent most of my time arranging and then cancelling road closures!