Using bladder tanks in the biges for extra fuel capacity ?

MapisM said:
I must say that I didn't think about that, but you are raising a very, very good point.
Not that I have any first hand experience with these tanks, but I do know how persistent diesel smell can be.
There was an almost invisible leak from a fuel filter when I bought my boat back in 2000, immediately fixed.
Long story short, after several attempts to find other leaks elsewhere in the following years, I just accepted to live with some smell - heck, it's an e/r, after all.
I can't positively say that it completely disappeared by now, after almost a decade and a half.
It surely isn't so obvious anymore, but according to swmbo, whose olfaction is better than mine, it's still perceivable... :ambivalence:
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Good job you used English to describe your SWMBO's attributes........"olfaction" sounds sooooooo much less risky than "olfatto"!!!!!!!!!!!!

:rolleyes::rolleyes::rolleyes::D:D:D
 
LOL, must admit that I wasn't even sure about the correct spelling...
...but I'm even more puzzled by what would the IT version sound like in EN!
Is that something which can be written on a public webpage without being banned? :D :D
 
In English, I guess it might sound like "Old Fatto". Literally someone who is old and fat. Eeekk! :eek::eek::eek:

Humble apologies to Bart for the thread drift.
 
Bart

If you were to have the tankage in another location, have you considered the fixed seating in the aft cockpit? I can think of two possible locations. One behind and under the fixed seating in front of your glass doors and the other across the stern under the fixed seating. I am guessing about 1000 litres for each location. Not sure if the deck construction would be strong enough to support the additional weight, plus it would all be towards the stern of the boat, so may not be ideal. Gravity feed to the main tanks ought to be simple enough to do.

Just a thought from an ex-raggie. :D
 
MapisM said:
I must say that I didn't think about that, but you are raising a very, very good point.
Not that I have any first hand experience with these tanks, but I do know how persistent diesel smell can be.
There was an almost invisible leak from a fuel filter when I bought my boat back in 2000, immediately fixed.
Long story short, after several attempts to find other leaks elsewhere in the following years, I just accepted to live with some smell - heck, it's an e/r, after all.
I can't positively say that it completely disappeared by now, after almost a decade and a half.
It surely isn't so obvious anymore, but according to swmbo, whose olfaction is better than mine, it's still perceivable... :ambivalence:
Click to expand...

Yup I guess there is a good reason that diesel tanks are usually confined to the engine bay. Like you I had a very minor leak from the tank drain pipe on my boat in the summer and the resulting smell of diesel pervaded the whole boat for days until I found the problem and rectified it. I can imagine that any leak, however small, from bladder tanks under the master cabin would produce very unpleasant odour in the accomodation. However as I understand it, Bart is planning to use these bladder tanks as temporary storage only so maybe it will be less of an issue
 
Regarding leaks/smell, the only place for a weepy leak in a sound bladder is the filler connection. The answer is simply to get uber quality gear here - there are plenty of fittings available that just do not leak.

I've had 2 boats with 1000+ litres of diesel under the master cabin bed, pressurised by 3m of head in the main tanks. I've never had any whiff of diesel whatsoever. All the fittings are hydraulic style crimped fittings specced for a few thousand psi. This is how you have to do it - top quality pipe fittings like you're building a nuclear reactor
 
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jfm said:
like you're building a nuclear reactor
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LOL, that's possibly the best description of the only boat on this planet which can run stabs at anchor out of battery power...! :cool: :)

...but I still wouldn't trust retrofitted bladder tanks to be as smell proof as I'm sure your system is...
 
MapisM said:
LOL, that's possibly the best description of the only boat on this planet which can run stabs at anchor out of battery power...! :cool: :)

...but I still wouldn't trust retrofitted bladder tanks to be as smell proof as I'm sure your system is...
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Are you thinking of weeps at the pipe connection MM? Or are you thinking a few smelly diesel molecules could osmotically ooze thru the bladder skin material? I'm not disagreeing with the possibility of either; I mean both need to be thought about and checked out. I have the luxury of 5mm aluminium plate
 
Well, tbh my concern was just generic, knowing as I said that it takes forever to get rid of diesel smell, however created, and regardless of how little the leak behind it actually was.
But coming to think of it, I wouldn't rule out also the possibility of ooze through plastic, at least over time.
No matter how good the skin material is, time and constant contact with diesel is surely bound to degradate it more than a 5mm alu plate, anyway...
 
I have never known purpose built fuel bladders to ooze fuel unless they have been damaged. The military use bladders for diesel and aviation fuel storage some as big as a football pitch they don't ooze or leak, I have also designed smaller bladder systems to carry aviation fuel on board transport aircraft, if there was any hint of vapour escaping into the aircraft they would not do it for H & S reasons, the CAA would not allow it. Any tank vents pass out of the fuselage usually

Recently the Australians decided to replace some of their storage bladders as they had been in use since the Vietnam war. If you buy the right quality of bladder and deploy them carefully, with proper quality fuel fittings, they will out last the boat.

In this case I would line the hull with a thick sheet of rubber and then lay the bladders on this, strapping them down with ratchet cargo straps.
 
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I missed this animated discussion on my subject :)

yes the smell is defo an issue,
let me first tell that this won't stop me continuing the poject.
as easy this plan is to try and test, as easy it is to get the bladders out when not satisfied.
and a day cleaning work in the bilges, of our crew, will then solve the majority of the smell problem,

but I do know that the type of bladders I've in mind to use, are sugested for diesel fuel, for usage inside the boat,
and they are supplied with brass fittings for perfect sealing,
they are even recommanded for black tank usage, that can count regarding smell issues.
although I don't know about the differences in molecular properties between diesel fuel and black water


Regarding the hoses I'm still in doubt,
I had in mind to use a good type of clear reinforced hose with twin high quality jubilee clips,
the main issue is logistics,
with custom made high pressure hoses, I have to open all acces for measuring lengths, then order the pipes, and after shipping them to Montengro,
re-open all bilges, for installing these hoses, and no possibility for adjustments on hose lengths
might reconsider, requires more and better planning, etc...

Q for Jfm, (or someone who knows) these pressure hoses, are they the rubber type, as Deleted User uses for hydraulics on his bulldozers,
or are these the plastic version ?
I have both models on different locations in the boat; passerel, crane, platform, rudder,
or is that something completely different ?
 
BartW said:
Q for Jfm, (or someone who knows) these pressure hoses, are they the rubber type, as Deleted User uses for hydraulics on his bulldozers,
or are these the plastic version ?
I have both models on different locations in the boat; passerel, crane, platform, rudder,
or is that something completely different ?
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I don't know a lot about hoses, Bart, but broadly speaking I believe that fuel hoses and hydraulic hoses are similar in concept ie a rubber hose protected by one or more layers of reinforcement, usually steel. But hydraulic hoses are usually rated to a much higher pressure, 300-500 bar on construction machines or maybe 50-100 bar on your boat hydraulic systems. I guess you don't need anywhere near that pressure in your fuel transfer hoses so IMHO you could use a low pressure reinforced hose with good quality double hose clamps as you propose but obviously the hose would have to be rated as being suitable for fuel. I doubt whether the clear plastic reinforced hose used for bilge pumping or black water would be suitable

Btw my company doesn't sell bulldozers:D
 
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the project of installing extra Bladder tanks in Blue Angel has been put in to action some time ago,
2 x 450l bladder tanks have been delivered,
2 x bilge positions have been prepared for this (moved some cables and hoses, and placed some plywood panels to box the space)
1 x hose from engineroom to collector has been put in place,
I'll post some pics later,
but first this question:

I'm looking for a collector where all the hoses from different tanks and pump come together,
to be installed centrally in the bilge between the cabins
and capable for future upgrade of 4 more bladder tanks

I'm looking for a brass collector, similar to this

collector%201.png


or this:

Collector2.png


but with outlets for 8 x 1" fittings
commonly available collectors for heating systems are 1/2"
anybody knows about a existing product?

if not we have to weld some threaded fittings on a tube,
or just connect many T's, ...
 
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