Sourcing Vacuum Hose

[Tom McCarthy]

Hi all,

I've got my turbo-pump (Oerlikon 151) and mechanical pump (Edwards RV3) and am buying the valves, clamps, gaskets etc. for the vacuum line. However, I haven't been able to source flanged flex metal hose for a relatively good price. I can get KF and CF flanged hose from Lesker, MDC, Ebay and many other shops, but there doesn't seem to be anyplace offering good value hose compared to other suppliers. Does anyone have a recommendation for where to source the hose?

Thanks,
Tom

[Richard Hull]

There is flex hose and then there is flex hose......... welding SS flex hose is highly flexible and ultra nice and ultra expensive. Pressure formed SS flex hose is less expensive, but still not real cheap. In addition, the pressure formed or SS ribbed hose is easily bendable to any desired shape and holds that shape. Welded flex is like a slinky. Add flanges to order and the prices sky rocket.

The larger the bore, the more expensive. I have some SS flex for sale in my trading post store here on Fusor.net but it is terminated with one inch compression fittings. Good luck on getting your two pumps coupled up and vacuum tight.

Richard Hull

[Jerry Biehler]

General vinyl hose is just fine for roughing. You usually need to support it with a spring on the inside or pay more and get the hose with a spring cast into it. There is also red gum-rubber hose. You can get PVC and gum rubber hose in heavy wall that will support itself without an internal spring too. There is no real need for stainless on a roughing line.

[Richard Hull]

I have, personally, always preferred a short length of heavy wall, red gum rubber tubing to isolate the roughing pump from the foreline system.

Richard Hull

[Liam David]

I use a piece of vinyl braided tubing from Home Depot between my diffusion and roughing pumps. It seals to hose barbs perfectly with hose clamps and it's cheap. I got 10 feet of it for $8.
-Liam David

[Rich Feldman]

When choosing hose for a roughing line, consider the "look" you want to achieve.

Wire-reinforced PVC hose, 1/2" ID, is still a penny a foot in my Trading Post store.
Plus actual postage from San Jose, CA, unless you pick it up here.
viewtopic.php?f=20&t=8035#p62931

[Tom McCarthy]

Thanks for the tips and advice.

It seems like I'll have to bite the bullet (for the turbo pump to chamber line) and I'll decide on what sort of tubing I'll use for my fore line tonight.

As you said Rich, the "look" is a bit of a factor, it might sound somewhat particular to the older guys here, but I'd like to have my set-up looking as nice as possible when finished...So flex metal hose is a bit ahead of PVC as of now. Nevertheless, I may well end up investing in some of your tubing Rich (won't be able to pick it up though!), but I may not either.

Thanks,
Tom

[fizz]

Hello Tom


If you can give me your required specification for your flexible hose NW10 or NW16 , I’m sure that I can help you.
Your answer to recalvac@aol.com UK address.

[Chris Bradley]

Wire-reinforced PVC hose, 1/2" ID, is still a penny a foot

Stiff is not so good.

I'd promote Richard's point - vibrations from a direct drive vacuum pump are not what you want to transmit, especially to a turbo pump or similar. I use a long piece of NW16 flexi, but that reduces pumping speed (though it does not really interfere with the overall pumping rate as that is at a much higher pressure than the limiting rate of the molecular flow side of the pump).

On the same point, try to isolate a direct drive pump away from any sort of table or chassis that a turbo sits on - those vibrations play havoc with the long [potential] life of a turbo. I sit each foot of mine on 4 layers of 5mm natural rubber, in turn sitting on some garden paving blocks.

[Dennis P Brown]

I have bought SS tubing, both 25 mm and 75 mm for under $20 for three foot sections and these have standard KF flanges. Searching e-bay and buying when opportunities arise is the key; since you are pressed for time, that isn't necessarily possible in which case standard thick walled vacuum hose is an excellent choice (and can use KF flange pipe adapters that fit standard vacuum parts.) Still, do keep your eyes open and watch ebay - deals like that occur (often mixed with other valuable vacuum components!) and need to be jumped on.