rubber bladder/hose

[DavidChr]

I am working on a project and require a tube that has elasticity as a major requirement. It needs to be able to be pulled, stretched and expanded.

It needs to be about 1/8 inch, inside diameter when deflated, and inflated, with air, via a handpump or bulb, to double its original size, so about 1/4 inch. I ideally should be able to be about 10 feet long in the relaxed state.

This is a prototype and therefore additional sizes will be required.

Any suggestions would be greatly appreciated.

 

[aspearin1]

Latex Hose?

ChemE, M.E. EIT
"The only constant in life is change." -Bruce Lee

 

[griffengm]

Does it need to seal a tube, clamp parts or form a barrier?
Each may influence the material.

Griffy

 

[DavidChr]

Thanks to both aspearin and griffengm for their input!

We started our trials with Latex tubes, but could not find tubes with a small enough outside wall to be inflatable with a hand pump similar to the hand pump on a blood pressure cuff. We were down to 1/64 of an inch and decided to look at other materials.

While our tube must be sealed at one end so it can be inflated, it will reside within a "sheath" of sorts and be protected. The far end of the tube will be sealed either during the manufaturing process or with a heat seal prior to installation in the sheath.

Again, thanks for your input. A great start!!!!

 

[pennpoint]

DavidChr
I think "griffengm" was thinking about this product line.
You may not need to invent something! But then again?

http://www.pneumaseal.com/

Good Luck
pennpoint

 

[griffengm]

David,
From your description, I am reminded of a Foley catheter of my intimate acquintance which uses a tube within a tube to inflate a small balloon used to retain the device in place. I believe water or saline solution is used to inflate the balloon.
Sounds like another place to look.

Griffy

 

[twinie]

David,

Rubber bands are manufactuered from a tubing called Gooch tube. The tube is extruded before cut into bands. Good news is it can be purchased in the extruded tube form.

A good source for this is

http://www.keenerrubber.com/

Althought the diameters you are seek are small Kenner advertises they work on custom sizes. I have used them in the past for an inflatable project prototype and they were very helpful folks. I used standard size tube though.

Good luck.

 

[DavidChr]

Twinie,

Thanks for your lead. Sounds good. Found the website and have already contacted them. I am concerned about using the material as a bladder, but I am anxiously awaiting their response. Thanks again for your input!

 

[DavidChr]

Twinie,

Quick update. Heard back from Keene Rubber, and they told me, "Sorry, that is not what we do, we manufacturer rubber bands."

Thanks for your help though! If you can think of anything else, please let me know! Thanks again for your input!

 

[amorrison]

From Twinie's post . . .

1. get a 1/8 inch teflon rod and dip it in a liquid latex solution.
2. let "dry" or cool
3. remove by "rollsock" method -since there will be many "layers" in the rollsock the outer layers will have to stretch many times that of the first layer-so your high material elasticity may be very nessary.


Maybe try with polyethelene(lubricated?) rod first -cheap/common.

Think condom manufacturing

 

[DavidChr]

GREAT IDEA!!!!!!!

I will let you know how it goes!

Thanks!!!!!!!

 

[amorrison]

Somethings to consider..

I recall sometimes kids party ballons acting strange during blowup the first time -some locations blew up first THEN other locations until full size.

You might buy a "pack" of long thin kids balloons and experiment with them.

Maybe the second blowup is different than the first due to residual effects of the first blowup?

Note: your diameter blowup ratio is 2:1 which is different than the kids blowup diameter ratio - effects ? ?

Try dripping the latex off the end of a vertical rod -this should promote equal wall thickness (critical ?)throughout the length and be sure latex temperature(viscosity) is the same throughout the length.

 

[pennpoint]

DavidChr

Did you really look at this site? I posted it, Jul 28th.

http://www.pneumaseal.com/

Did you talk to anyone there. These people do what you are tying to do at least from what I get from your discriptions and return comments.
They inflate tubes.

Regards
pennpoint