Anyway my inflated tube application. Which is still in the theoretical stage is something like this.
There is a device that weighs 100kg, it sits 30mm off a flat surface (on 4 corner legs) it has a flat bottom plate, surface area 500mm by 500mm.
On a regular basis I need to lift the device 300mm.
For various reasons there is no ability to use any form of hoist or leverage, I simply need to vertically dead lift the 100kg device 300mm.
The idea is to slide a deflated tube, in a canvas cover, no more than 30mm high under the device, then inflate and lift it.
Vehicle access could be an issue, given some of these devices are on the 2nd floor lol.
I already have 6 medium sized 16 litre Catalina dive bottles, they weigh roughly 9kg. But are generally to big to use as a range of other equipment is carried so I'm thinking more of a small compressed air bottle slung over the shoulder. I haven't yet built the tube in a bag device, so I havnt filled it with air to measure the volume or stability, this is just at the theoretical stage.
But my maths ain't what it used to be, and I didn't want to put it all together then find I still need to lug big air bottles around. So I thought I'd work out the air volume first.
Quote
medcare (117 117 positive feedback) 10:23 pm, Tue 5 May #26 Interesting challenge- personally i would be heading more to 4 small scale house jacks lifting together-either hyd or air
daz59,
May 6, 8:35pm
I must be up too late but I got it to be 38.5 litres exactly half of what you get?. I worked out the ellipse area is 35,000mm, and length 1100mm, using the middle of the tube for the average length (350mm diameter)
daz59,
May 6, 8:44pm
If it is 38.5L at 10PSI and you need 50 of them then you need 1925L at 10PSI. 3000psi is 300 times the pressure of 10PSI so you should divide 1925 by 300 that gives you 6.4L tank at 3000psi to pump up that tyre 50 times. you will need slightly more as once that little tank gets down to 10PSI it wont pump up the tyre to full pressure. Chas10, maybe I have worked that out all wrong because it far different than your numbers?
snoopy221,
May 6, 8:49pm
arrrr bra. is dis where i add a 100 Kilos on TOP of ya standard temp and pressure calcs?
mmmmm 4 small light house jacks working together with a 300 mil lock is SAFE,,,,,,, After all unit dimensions are UNKNOWN try lifting 100 KG that is six feet high 300 mill with ONE? tire?
R1=r-sqr(z*z-y*y) inner displacement from center as func of y R2=r+sqr(z*z-y*y) outer displacement from center as func of y
v1(y)=s0*b0*I< pi*R1*R1 > dy ie integrating with respect y = >pi*s0*b0*(r*r*z -2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) v2(y)=s0*b0*I< piR1*R1 > dy ie again ntegrating with respect y = >pi*s0*b0*(r*r*z +2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) where y=75 orthogonal displacement off torus plane ie volume bewtween 0mm displacement and 75mm (note scale/synnetry factors s0 and b0 make isomorphic to 300mm case.) then vol(y)= v2(y)-v1(y) =>2*pi*s0*b0*r*z*z*arcsin(y- /z) ==38,840,720.625 cubic mm ==38.84 L
R1=r-sqr(z*z-y*y) inner displacement from center as func of y R2=r+sqr(z*z-y*y) outer displacement from center as func of y
v1(y)=s0*b0*I< pi*R1*R1 > dy ie integrating with respect y = >pi*s0*b0*(r*r*z -2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) v2(y)=s0*b0*I< piR1*R1 > dy ie again ntegrating with respect y = >pi*s0*b0*(r*r*z +2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) where y=75 orthogonal displacement off torus plane ie volume bewtween 0mm displacement and 75mm (note scale/synnetry factors s0 and b0 make isomorphic to 300mm case.) then vol(y)= v2(y)-v1(y) =>2*pi*s0*b0*r*z*z*arcsine(- y/z) ==38,840,720.625 cubic mm ==38.84 L
R1=r-sqr(z*z-y*y) inner displacement from center as func of y R2=r+sqr(z*z-y*y) outer displacement from center as func of y
v1(y)=s0*b0*I< pi*R1*R1 > dy ie integrating with respect y = >pi*s0*b0*(r*r*z -2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) v2(y)=s0*b0*I< piR1*R1 > dy ie again ntegrating with respect y = >pi*s0*b0*(r*r*z +2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) where y=75 orthogonal displacement off torus plane ie volume bewtween 0mm displacement and 75mm (note scale/synnetry factors s0 and b0 make isomorphic to 300mm case.) then vol(y)= v2(y)-v1(y)
=>2*pi*s0*b0*r*z*z*arcsin(y- /z) ==38,840,720.625 cubic mm ==38.84 L
R1=r-sqr(z*z-y*y) inner displacement from center as func of y R2=r+sqr(z*z-y*y) outer displacement from center as func of y
v1(y)=s0*b0*I< pi*R1*R1 > dy ie integrating with respect y = >pi*s0*b0*(r*r*z -2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) v2(y)=s0*b0*I< piR1*R1 > dy ie again ntegrating with respect y = >pi*s0*b0*(r*r*z +2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) where y=75 orthogonal displacement off torus plane ie volume bewtween 0mm displacement and 75mm (note scale/synnetry factors s0 and b0 make isomorphic to 300mm case.) then vol(y)= v2(y)-v1(y)
=>2*pi*s0*b0*r*z*z*arcsin(y- / z ) ==38,840,720.625 cubic mm ==38.84 L
R1=r-sqr(z*z-y*y) inner displacement from center as func of y R2=r+sqr(z*z-y*y) outer displacement from center as func of y
v1(y)=s0*b0*I< pi*R1*R1 > dy ie integrating with respect y = >pi*s0*b0*(r*r*z -2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) v2(y)=s0*b0*I< piR1*R1 > dy ie again ntegrating with respect y = >pi*s0*b0*(r*r*z +2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) where y=75 orthogonal displacement off torus plane ie volume bewtween 0mm displacement and 75mm (note scale/synnetry factors s0 and b0 make isomorphic to 300mm case.) then vol(y)= v2(y)-v1(y)
=>2*pi*s0*b0*r*z*z*(arcsin(- y/z)) ==38,840,720.625 cubic mm ==38.84 L
R1=r-sqr(z*z-y*y) inner displacement from center as func of y R2=r+sqr(z*z-y*y) outer displacement from center as func of y
v1(y)=s0*b0*I< pi*R1*R1 > dy ie integrating with respect y = >pi*s0*b0*(r*r*z -2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) v2(y)=s0*b0*I< piR1*R1 > dy ie again ntegrating with respect y = >pi*s0*b0*(r*r*z +2r(1/2(z*sqr(z*z-y*y) +(z*z*arcsin(y/z))) +z*z*z-1/3*n*n*n) where y=75 max orthogonal displacement off torus plane ie volume bewtween 0mm displacement and 75mm (note scale/synnetry factors s0 and b0 make isomorphic to 300mm case.) then vol(y)= v2(y)-v1(y) =>2*pi*s0*b0*r*z*z* arcsin(y/z) and therefore for maximised volume at y=75, =>2*3.141*2*2*175*75*75* arcsin(1) ==38,861,567 cubic mm lol or about 38.86 L
hmmm, probably wrong but was fun trying.
marzuka,
May 7, 1:56am
lol, what happened there? I was just trying to get rid of the minus sign that mysteriouly kept showing up in the line
=>2*pi*s0*b0*r*z*z*arcsin(y- -
after each edit for no logical reason.
Oh well apologies for that.
chas10,
May 7, 4:30am
Yes youre right I got the circumference wrong, I used diameter instead of radius.
mrfxit,
May 7, 6:51am
LOL, thats what you get for showing off
kazbanz,
May 7, 7:30am
medcare--its kinda academic anyways. The bottle you'll be using is a scuba tank. So you don't have unlimited choices in reality In nz ignoring tiny pony bottles you are pretty much limited to 10.12 and 15l steel tanks and 11.5 l ally tanks. Given the importance of the job unless the tank needs to be carried a distance I'd stick with a 15l -on the basis that redundancy is important. Hey sorry to be a know it all but what it will be is a first stage regulator on the tank then an inflator so youll need to allow a bit of wastage. also if you talk nicely to the LDS they are often happy to crank the pressure a bit -220bar/3300psi isn't unheard of. -Burst pressure is a coupe of thousand psi north of that so well under burst disk pressure
Incidently "somebody somewhere" has I have an old/knackered dacor BCD you would be welcolm too if you want to carry the tank on your back. Ie it wont inflate but the carrying straps are fine as is the backplate.-turns the tank into a heavy backpack
medcare,
May 7, 9:09am
Thanks Kazbanz.
Yes air bottle capacity is important, so I may end up with 2 x Catalina AL13, aluminium dive tanks with 13ft cubic capacity and weigh 2.5Kg each, one as a back up in the car if the other is empty. Investment costs are no problem if the process eventually works. A lot of extra stuff is carried and the distance from the car to the site could easily be several hundred metres+ so size and weight is important,
My happy state would be a 2-3Kg bottle in a bag slung over the shoulder.
I thought my existing Catalina air bottles were 16litre but they are actually 30litre, so at 5kg and 500mm long are too cumbersome to carry.
I was probably dreaming to get 50 lifts per bottle but I tend to aim high then if the numbers don't stack up settle a bit lower, so even 25 lifts a bottle would do.
medcare,
May 7, 9:18am
A good example of what I was originally looking for is this kids inflatable Ottoman: The size of 500mm across and 300mm high was spot on.There are inflatable Ottomans on TM, but they are 600mm+ across. Any bigger than 500mm and it won't fit under.
Main problems are they don't ship to NZ There was also a lot of 'dead' space in the middle, which would just take extra air from the bottle to fill. So I thought a tube with no centre would use less air. Albeit by filling the whole Amazon Ottoman then I assume I get a better surface area/weight ratio, which could mean a lower inflation pressure is required.? But that sort of number crunching is beyond me these days :-)
kazbanz,
May 7, 10:00am
Medcare--my maths must be really screwed up.AL13 is basicly a little bailout in my mind.Fire extinguisher sized. I think maybe we are getting our terminology a bit mixed up. When you refer to AL13 that is American terminology. To give you an idea a standard dive tank is al40 or Al60 That translates roughly to 10 and 11.5liter how we think The biggest dive tank a normal human being can carry would be 15litre a normal recreational dive tank is 11.5 ally of 12 litre steel. that gives about an hour of dive time at rec depths You have done my head in trying to think of the application out in the field.
medcare,
May 7, 10:14am
This is the spec sheet for the Catalina dive tanks.
My existing 6 dive tanks are the AL30, 2nd graph down. The ones I'm thinking of using for this application are the AL13's
We may be confusing cubic feet with cubic litres, damn Americans. no wonder they almost lost us the war :-)
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