[Roy Harding]

I did baffle a tank, but now have a 650 upright. Keep your eye open for a second hand one. I got one off ebay with all the fixings and bras taps for £85 from Cwmbran.

Roy

[elite mike]

hey tosh

go round that round about at the top of town ,with an unbaffled tank 

better ride than alton towers 

[SPE]

I tried baffling my 650 ltr layflat with drainage pipe, unfortunately due to the dimensions of the tank I could'nt fit any more than 2 ft sections in and they floated banging around when half full, was horrible.

solution

I bought 25 meters of perforated 80 mm diameter land drainage hose off ebay, stuffed the whole lot in there, sorted 

[LWC]

Get it and stick some as said some drainage piping in there!

Someone i know had a 1000l on in his all full of drainage piping and it was fine, dont think he ever filled to top but wouldnt of been far off 800 in there.

As long as its secure and has something in there to stop slosh i dont know what all you guys worry so much about. My 400l tank has only got 2 cut outs of it. Other than that theres nothing. I think drainage piping coiled round in there would be way better than our standard baffled tanks.

Get it tosh 

[mikecam]

they would not put them in if there was no reason for it, they are there to aid not when tank is at its fullest but as it is emptying.

They're there to give strength to the tank and not for anti slosh purposes. That tank i pictured still has almostthe same slosh as an unbaffled one.

should you need the mathimatical calculations for working the diference out then here
http://www.benthamscience.com/open/totj/article/V004/23TOTJ.pdf
I would have typed the equations on here but it dont like the fonts

Look at the pictures in the study you provided a link for, yes cylindrical tanks.
Oh, did you read this bit.....
Alternatively, anti-slosh properties of baffles designs
have been investigated through laboratory experiments
employing small size tanks of different geometry [18,20-22].
These have generally studied damping properties from free
oscillations or slosh under harmonic or single-cycle
sinusoidal inputs. Such excitations do not provide sufficient
data relevant to the effectiveness of baffles under a braking
input.

There's a reason IBC's don't have bafles in and they're desiged for road transport.
Anyway, meanwhile there's loads of people driving about fine with unbaffled tanks and lots of people driving about with baffles in mistakenly thinking they are safe!!!
 Talk about scaremainering.

[weetot]

Here we go again !! Take a bit of knowledge like a baffled tank reduces sway/lag or whatever and then exaggerate it that anything that is unbaffled is dangerous. A 5 or 600 litre tank unbaffled is not dangerous or a liability. Here is a baffled 500 litre tank........


here's another shot of it........




Now the reality is that the baffling does not do a lot to aid  reducing any tank roll/sway. But the fact it does have a baffle will keep most simpletons happy. Baffling a fluid tank is primarily for reducing surge from a long cylindrical tank, NOT these small cuboid tanks we have in our vans.

they would not put them in if there was no reason for it, they are there to aid not when tank is at its fullest but as it is emptying.
the baffles are there to counteract slosh, the lateral movement of fluid within a tank. lateral fluid movement produces presure in both horizontal and vertical planes and in both liquid and gas states
this presure transfers through the vessel and suporting structure.
presence of baffles
could help reduce the peak magnitude of lateral slosh force
developed under applications of simultaneous lateral and
longitudinal acceleration excitations, and that an oblique
placement of transverse baffles would yield greater reduction
in the peak lateral force. This is attributed to the oblique
baffles providing considerable resistance to slosh in both roll
and pitch planes.

should you need the mathimatical calculations for working the diference out then here
http://www.benthamscience.com/open/totj/article/V004/23TOTJ.pdf
I would have typed the equations on here but it dont like the fonts

yes I mentioned gas before, what is above the water in a tank? dont say nothing! its air and air is a gas. tanks are vented to both allow air to enter as liquid exits and also to stop presure spikes during slosh

you also have mass vs weight, given 1 kg = 9.8 newtons then a 500 ltr tank would be 4.900 newton. put this 500 ltr in a 600 tank and you will have all this moving around. though the water at the bottom will be moving a lot less due to the upper mass.

Well that’s it for now and just to be extra polite i will refrain from using the word simpleton...

If Stan Ogden were still alive, and heard you sayin' all that, he'd kick your ass...

[Tom White]

I bought 25 meters of perforated 80 mm diameter land drainage hose off ebay, stuffed the whole lot in there, sorted 

Thanks, SPE, I've just e-mailed the guy whose willing to swap, to see if he still wants to swap.  Even if it turns out not to work, I can stick it in my shed and use it as a holding tank in Winter in a hopefully frost free environment.

Cheers guys for a lively discussion.

[mci services]

I have no problems with the unbaffled tank thing, just the payload bit, but if you watch what you carry and don't fill it, then fair enough as far as I am concerned, I work on my own and 400 litres sometimes is just not enough, but I like it so I can go home

[Tom White]

I have no problems with the unbaffled tank thing, just the payload bit, but if you watch what you carry and don't fill it, then fair enough as far as I am concerned, I work on my own and 400 litres sometimes is just not enough, but I like it so I can go home

500 litres will be fine for us.  I only carry short lightweight ladders for access.  Wor Lass can only weigh about 50 kg (if that).

500 litres  of water =                                                                       500kg

Me and Wor Lass =                                                                         150 kg (tops)

Fuel =                                                                                                50 kg (tops)

Other paraphernalia including lunch and the weight of the tank =   100 kg (tops)

Still leaves us 65 kg underweight; but probably more.  I'd like enough water to comfortably last us till about 1 or 2 pm, until I drop Wor Lass off home, and fill up to do some more work by myself (I do the drive betweens).

But sometimes, depending on the work, we seem to be running really low by midday; so another 100 litre capacity would be great.

[mci services]

Yes Tosh I agree, I did a post on another forum where I guessed the weight of everything including ply lining, fuel, battery, hose reels, and all the rest and 500l was just within but close, but I do carry a couple of sets of ladders and loads of other rubbish I don't need, so I think you will be fine I wasn't trying to put you off, I used to carry 500l when I had a lad with me, the extra was in containers

[christopher b]

you would have slosh in any type of tank, and that report was the first one that i remembered from the studies and yes is aimed at cylindrical tanks.
There was also an independent report made for an American fire office who had as part of their fleet pickups fitted with “non-cylindrical tanks” after said report was released the fire department had all new systems fitted with baffles and the older ones fitted with ball systems
http://www.rapidspray.com.au/content_common/pc-ball-baffle-system.seo
Yes IBC’s don’t have baffles, and we are not driving 32 ton articulates either or rigid. You would also find that they are only transported when full giving no room for movement.
Yes baffled tanks are not a cure they are merely an aid and the safety of any tank is equal to the securing system used and its ability to hold said tank in place to stop movement.
Have a look around you will notice that the tank systems that are on the market and are thatcham approved are all fully baffled.
Baffling dose not STOP slosh it merely reduces it, at no point did I say it stopped it
And no I’m not scaremainering I am merely stating there is a difference between baffled and non-baffled tanks. It is down to each and every individuals own choice as to fit either type, it is also each person’s responsibility to ensure it is securely mounted
Personally if it was scientifically proved that having a big red nipple on the side of the tank gives you a 1% increase in safety then I’d go for it, I don’t give a hoot about the tank I am more interested in my personal safety  and in the unfortunate event of an accident the safety of others