Square/Rectangular LPG tanks????
Submitted: Tuesday, Aug 15, 2006 at 18:31
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Jimbo
Why hasn't someone developed a cube shaped LPG
tank.
By my calculations a cubic style
tank would hold at least 35% more fuel than a cylindrical
tank of the same length and width. Hence you could store more fuel in the same underbody cavity.
Now I do understand that a
tank with corners has some weak points and would not withstand the same pressure as a cylindrical
tank. However, would it be as simple as, say, increasing the thickness of the steel a little to offer the same pressure holding capacities?
Be gentle with me, I'm a simple man.
Reply By: Alloy c/t - Tuesday, Aug 15, 2006 at 19:00
Tuesday, Aug 15, 2006 at 19:00
Jimbo ,you answered your own query , not the thickness the problem ,shape , a circle/cylinder/ball is stonger by a factor of X times over a rectangle/square /box . back to the drawing board ?? lol
AnswerID:
189164
Follow Up By: Patrol22 - Wednesday, Aug 16, 2006 at 12:47
Wednesday, Aug 16, 2006 at 12:47
Yep - never seen a pressure vessel yet that is anything other than monocoque - ie egg shaped/cylindrical/spherical.
FollowupID:
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Follow Up By: Mr Fawlty - Wednesday, Aug 16, 2006 at 16:21
Wednesday, Aug 16, 2006 at 16:21
Ohhhhhhhhhhhh Yew Bewdy A topic which I can discuss with authority....I have plenipotentiary powers to design & manufacture steamboat boilers in the ACT so I do know a bit about this.... WOW at last something I can get my dentures into.. Oh boy Oh boy...
Yes if you want to see a cuboid pressure vessel take yourselves off to
Mannum & have a look at the Boiler sitting in the
park... It's a fake, the real one is in the adjacent museum....Notice how William Randell who built it got nervous at the sides bulging so put chains around it to strengthen it...
History of the Murray is absolutley fascinating....
While you are there wondering at this marvel take a trip on the Marion, you will enjoy it.
FollowupID:
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Reply By: Hairy - Tuesday, Aug 15, 2006 at 19:02
Tuesday, Aug 15, 2006 at 19:02
Yeh,
I was just talking about that today, the biggest issue I have with LPG is the amount of room the
tank takes up. And it would be possible, just the weight would be the next problem, It would need a lot of internal gussets.
I dont know anyone who has tried to get one engineered but its worth a thought.
Its not really that the corners are weak but more of an issue of keeping the flat sides flat.
It would be worth looking into.
Cheers
AnswerID:
189165
Reply By: jackablue - Tuesday, Aug 15, 2006 at 19:56
Tuesday, Aug 15, 2006 at 19:56
Why don't the
supermarket chains just offer a % off docket instead of the cents per litre. The discount amount has stayed the same even though to fill your
tank has gone up almost double in the past 3 years!!!!!!!!!!!!.
Before - 85 litres @ 0.75 - Discount $3.40 fill
tank $63.75
Now - 85 litres @ 1.35 - Discount $3.40 fill
tank $114.75
Cheers
Jackablue
AnswerID:
189177
Follow Up By: Member - Oldplodder (QLD) - Tuesday, Aug 15, 2006 at 20:10
Tuesday, Aug 15, 2006 at 20:10
A bit OT, but remember when they first came out and there were 6c and 8c discounts? Now there si only 4c discounts. Woolies discounts are getting less!
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Follow Up By: GaryInOz (Vic) - Tuesday, Aug 15, 2006 at 23:40
Tuesday, Aug 15, 2006 at 23:40
Ppl are still foolish enough to believe the dockets are actually worth anything?????
PPl
shop and buy fuel on a Thursday or Friday. All the specials go off the shelves Wednesday.......
Do your shopping Mon pm or Tue, and buy fuel only on Tue. You will save a hell of a lot more than the $2-5 (or 40-100 litres) you will at the end of the week.
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Follow Up By: Patrol22 - Wednesday, Aug 16, 2006 at 12:45
Wednesday, Aug 16, 2006 at 12:45
They would probably claim it is a matter of 'margins' ie the wholesale price of oil/petrol/diesel has gone up whereas the retail margin has remained relatively static thus the discount remains static. Don't know it this is true or not but my guess is that the real profits are going to the oil companies and not the retailer.
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Reply By: garryk - Tuesday, Aug 15, 2006 at 19:57
Tuesday, Aug 15, 2006 at 19:57
G'day.
I agree with the space taken up by a round
tank being an issue and know that there are real issues with a rectangular
tank shape
But why not a
tank shaped like a Ford Falcon header
tank ?
No idea of how to calculate the volume of that shape however
for anyone not familiar with the shape I mean , it's a bit like an egg carton
garryk
AnswerID:
189178
Reply By: Andrew-rodeo - Tuesday, Aug 15, 2006 at 20:02
Tuesday, Aug 15, 2006 at 20:02
I am pretty sure it cant be done. there is no strength in flat sections of metal without reinforcement. Same deal as body panels the bonnet requires a lot of reinforcement, the quarter panels do not becuase they are curved. The only current method of fitting round tanks in square spaces is the use of manifold tanks or donut tanks.
AnswerID:
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Follow Up By: Member - jeff M (SA) - Tuesday, Aug 15, 2006 at 20:26
Tuesday, Aug 15, 2006 at 20:26
Great idea as far as space saving, fabrication costs would be a killer.
Round tanks are welded with a rotator.
But I'm sure it could be engineered. But the cost. ( Scary )
Cheers Jeff
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Reply By: Member - Oldplodder (QLD) - Tuesday, Aug 15, 2006 at 20:17
Tuesday, Aug 15, 2006 at 20:17
Alloy and Hairy have it spot on.
Read the pressure vessel code sometime.
Not sure what pressure LPG is stored at, but when you do the calcs on a rectangular
tank, you start thinking that a rectangular
tank is so heavy, maybe a circular one with hemspherical or dished ends would save a lot of weight, welding and cost. :-) Now every one just goes circular because you know it is the most effecient. Can get away with rectangular for special low pressure compressed air if you have too.
AnswerID:
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Follow Up By: Mr Fawlty - Wednesday, Aug 16, 2006 at 16:26
Wednesday, Aug 16, 2006 at 16:26
LPG liquification pressure is about 650kPa...The LPG tanks are tested to twice this from memory....Not hard to make, just untill now there has been no demand for one that fits the shape of the fuel
tank that could be taken out. Other considerations are the conservatives who worry about explosions in an accident because as you have all seen on TV every car of american manufacture explodes on impact with anything....
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Reply By: Robin - Tuesday, Aug 15, 2006 at 20:28
Tuesday, Aug 15, 2006 at 20:28
Not so silly , as said it could be done with size and weight, and part rounded corners.
But their is another possible solution - down at
United headquarters I saw a composite gas
tank. (sort of fibreglass - not really correct)
Still cylindrical but massively lighter, allowing for other designs without less total weight than steel..
Don't know much more - think these units have to be re-tested every 3 years
but development on going
Robin Miller
AnswerID:
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Follow Up By: Scubaroo - Friday, Aug 18, 2006 at 23:44
Friday, Aug 18, 2006 at 23:44
Firefighters have been using composite tanks for years - pumped to 4500psi or so. Bloody strong stuff. Surprised no-one has thought of it for LPG - only problem is I believe that it is somewhat expendable, and has a usable life of only 10 years or so before the tanks are condemned.
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Reply By: Trevor M (SA) - Tuesday, Aug 15, 2006 at 22:06
Tuesday, Aug 15, 2006 at 22:06
Just thinking "outside the square" for a minute (or in this case "outside the cylinder").... how about a cylindrical gas tank within (or surrounded by) a square petrol tank to utilise the rest of the space?
I hear the laughing already but for every 99 stupid ideas 1 may be worthwhile!
Trevor
AnswerID:
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Follow Up By: Jimbo - Tuesday, Aug 15, 2006 at 22:17
Tuesday, Aug 15, 2006 at 22:17
I'm not laughing, that is pure genius stuff.
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Follow Up By: GaryInOz (Vic) - Tuesday, Aug 15, 2006 at 23:44
Tuesday, Aug 15, 2006 at 23:44
I'm with Jimbo...............
Bloody genius.
PATENT OFFICE TOMORROW!!!!!!!!!!!!!!!
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Follow Up By: Michael ( Moss Vale NSW) - Wednesday, Aug 16, 2006 at 09:59
Wednesday, Aug 16, 2006 at 09:59
Dont bother
Gary, i'm walking up the stairs Now LOL!!
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Reply By: Mr Fawlty - Wednesday, Aug 16, 2006 at 16:32
Wednesday, Aug 16, 2006 at 16:32
Short answer here is that they are made & fitted in the UK. made from Carbonfibre/ epoxy over a thin aluminuim tank merely used to keep the shape during manufacture...Similar process as used to make composite scuba tanks...Any shape tank is possible but you will still find curves as sharp corners in most materials will be a weak point in the finished product. You have all seen the very expensive 9kg LPG bottles for use in "Marine" environments????
AnswerID:
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Reply By: Steve_D40 - Thursday, Aug 17, 2006 at 15:19
Thursday, Aug 17, 2006 at 15:19
A mate bought a Winnebago over from US a few years back and it had rectangular lpg tanks. Had to take them out to get it regoed over here, but I believe they fell back in after rego?
One thing the yanks appear to be able to do?
cheers
Steve
AnswerID:
189501