high pressure hoses

[Cave Diver]

roakey once bubbled...
The hydraulic hose that the dive shop got had perferations in the outer jacket so it didn't bubble. Why the outer jacket had perforations I don't know, but it was a regular pattern so obviously part of the design.
Roak

The high pressure quick disconnect hose that came with my Aeris 500AI computer was like this. It had little pinholes going the entire length of it. Looked sorta like one of those soaker hoses you put in your garden.

I have noticed that sometimes, usually during the first 5 minutes after turning air on, that it will have little tiny bubbles escaping from these holes.

After a while, not sure how long, it stops. Haven't really figured out why, as this is the only hose I have ever encountered like this. <shrug>

 

[pescador775]

Hydraulic hose for $10 is cheap indeed since the end fittings usually cost that much. How are you going to clean the inside of the hose? Flushing with a special (expensive) solvent and blow dry will do it. Hydraulic hoses are usually stiff and awkward to work with. They can drive one crazy trying to bend and position. Under pressure they try to 'unwind' and spin the tank making the gauge turn away from view. A temporary fix when your good, teflon lined hose gets 'lost', maybe. I can't see pumping oxygen through it. Air is OK, the leakage is not enough to worry about for a six foot length.

 

[FredT]

Hydraulic hose has a thin jacket. If the hose inside fails or weeps it's no big deal since the jacket contains the very small volume of oil and the reinforcing is not harmed by the oil. If the same weepage happens in a pneumatic line the pressure builds up until the hose jacket fails catastrophically. This is not fun and the "surprise" factor can also cause additional injuries. To prevent the jacket failure the hose jacket ONLY is pricked with a needle wheel. Almost all pneumatic hose will have a pricked jacket, exccept those made to be submerged. Thermoplastic and thermoplastic multiline hose assemblies are generaly avialable either way. Parker also sells a tool to prick the basic hydraulic hose jacket if the hose is going to be in pneumatic service.

I've assembled many hundreds of hose lines, ratings to 10,000 PSI. As a rule of thumb is it impossible to get the end fitting in place without lubing the hose and nipple on almost every type of hose I've worked on if the WP was over 200psi. Larger hoses take lube and a sledge to assemble!

Check with Parker fo their thermoplastic lines. Smaller sizes (big hoses are NOT needed for fill, and a small lline can be assembled run through a larger guard hose if kinking or physical damage hazards exists) are rated for 5000 to 10000 psi. Fittings start to be the limitation once down around 1/8" hose. These CAN be assembled witout the heavy lube, but may not be suitable for pure O2 in all cases.

FT

 

[cclark]

roakey once bubbled...

One of the shops here in town has a bank that's located in a trailer in the parking lot (so they can take the bank on the road) with a fairly long (50') hose run into the shop....

Roak

Yesterday I got home, kind of punchy after making my town run (shopping, Post Office, bank) and decided to cool out in cyberspace for a while.
Since my bank is in a trailer, (I suppose it's manager would insist on calling it a "mobile office building"), I had to read Roakey's post about 4 times before I could shift gears enough to make sense of what he was talking about.

I'd waited in line a half-hour to get a check cashed, and was extremely envious of the shop-owner that had a hose running to the bank, no matter how leaky. I just couldn't figure out how it worked. Perhaps like those lines I'd seen in Home Depot running from the cash registers off to someplace mysterious?

And what to make about "tak[ing] the bank on the road"? We DO have a Post Office in a van, which drives out to our "second" town each day, but a bank, especially in the Wild West? Sounded like a Butch Cassidy wet dream.

Anyways, I finally got it. Roakey, thanks for your illustrative description of hydraulic hose failure. Next time I read about our current low rates of inflation, I'll know what to attribute it to.

Yrs,

Chris