On 12/16/2014 9:53 PM, Larry Jaques wrote:
On Mon, 15 Dec 2014 21:49:54 -0600, Martin Eastburn
wrote:

On 12/15/2014 9:18 AM, Larry Jaques wrote:
On Sun, 14 Dec 2014 20:19:48 -0600, Martin Eastburn
wrote:

On 12/14/2014 8:07 AM, wrote:
Trucks, Freightliner, Volvo, Kenworth, etc, normally have air system
set @120psi or so.

I've found the highest I can inflate the tires using the truck
air system & a 50' hose is 97-98psi.

Need a bit more. Looking for 115psi on the steers(cold) & 105psi on
the drives.

Was wondering if an air powered booster pump would be possible?

Say, 50% of the airstream as high-pressure supply, and the rest to
drive the booster?

If not practical, any easier/better way?

thanks

gary

A long hose with small center hole is a high resistance.
If you have joint leaks, the pressure will drop before you
get to use it. You are dropping (maybe ) 20 PSI in the hose.
Try a larger ID hose with fewer connections.

Martin, the resistance in the hose is only during full flow.
Give it 5 seconds and the full pressure hits the far end.
It's the law!


Does the pump put out 120 really ?

Good question. Gauge error?

If there is flow the restriction will drop pressure.

HIGH flow. How much flow is going to happen between 90 and 105psi,
though? Some, but low. There should be very little pressure drop.

If there are no connectors or If the connectors are 'air tight'.
They are likely leaking on both ends and in the middle if there is one.

A local tank on the end would be best - have the long hose fill it and
then start to use it from the local tank - as it refills but the tank
supplies the inrush flows and the big squirts setting the connector onto
the valve.

If you measure static pressure you should read 120.
If you measure dynamic pressure (at use flow) it will
be lower. You might read 20 if the use of the air is great.

Of course, but we're talkin' airing tires on a truck from a pump on
the vehicle.


The tank is to far away to help the out rush.
A local tank would be of better use - e.g. fill it and use
from it while refiling from the long hose.

For a flat, yes, but to go from 100 to 115?

--
Obstacles are those frightful things you
see when you take your eyes off your goal.
--Henry Ford