Regulator safety

I have propane and oxygen regulators made by Uniweld in 1995 sitting
unused in my studio. I stopped using them because the pressure in
the propane tank would pulse and drop when used at lower PSIs. I use
a Meco midget, and a Smith little torch, depending on the job. I
have several questions for Orchid members:

Has anyone else experienced the pulsing with their regulators? (It
happens when I make chain, and I make a lot of chain.) Does this
pulsing have anything to do with my check valves? (tanks are outside
and protected, pulsing is the same regardless of temperatures, or
fullness of tanks.) Is it worth having them repaired, or should I buy
new ones? (I have checked my area for repair shops, and I would have
to send them to Uniweld in Florida.) If I need new ones, does anyone
have favorite brands for quality and reliability?

I truly appreciate any and all suggestions.

Thanks!

For low flow rates of any gas, wether fuel or oxidiser, 2 stage
regulators work the best.

If you dont have this type, try increasing the line pressure and
throttling this pressure at the torch valve.

Let us know if this works.

Have you checked your local welding supply shop? Almost every town
of reasonable size has such a shop that works with equipment like
yours all the time.

fred

It is likely a failed diaphragm. I’d try to get it repaired.

Do you release diaphragm pressure when you shut off your gas or
oxygen?

Judy Hoch

I do have two stage regulators, Ted, and when I bump up the line
pressure, I get a lot of flame blowout at the torch.

Fred, I have tons of welding shops around me, but no one deals with
Uniweld, the nearest one is 4 hours away.

Judy, I suspect you’re right, I just don’t know enough about
diaphrams to understand how they fail.

I think I’ll just send them to Uniweld in Florida to have them solve
the mystery. Thank you for your helpful answers.

I do have two stage regulators, Ted, and when I bump up the line
pressure, I get a lot of flame blowout at the torch. Fred, I have
tons of welding shops around me, but no one deals with Uniweld, the
nearest one is 4 hours away. 

Youd should have a screw valve at the torch.

thats what i meant by turning the gas flow down there.

There is a screw valve on the torch, Ted, but with the higher
pressure from the tank, the pulsing is greater and faster when I open
the torch valve. I can light the torch, and the flame gets blown out
on the next pulse. Repeatedly. I have not had this problem with other
regulators, which is why I asked if other jewelers have a
favorite regulator brand. Thanks for your help.

Judy

Just have your local welding place or Uniweld replace the diaphragm.
As for shutting down the tanks, turn tank valve clockwise till you
can’t go any further, and then bleed the hoses. do not light the gas
while youare bleeding. Smith Company said it was too dangerous. Cindy
Eid had to call Smith Co. and get confirmation. Then turn regulator
knob counterclockwise till it feels loose but not falling out. That
way your tank is properly shut down.

I discovered I have a backup regulator that the dial does not work so
that will be going in for repair or replacement of dial gauge. I have
multiple regulators I keep on hand. GRrrrr…always something. Now
I have to try to fix a buffing machine at the school I teach at.

Joy
Regulator safety

There is a screw valve on the torch, Ted, but with the higher
pressure from the tank, the pulsing is greater and faster when I
open the torch valve. I can light the torch, and the flame gets
blown out on the next pulse. Repeatedly. I have not had this
problem with other regulators, which is why I asked if other
jewelers have a favorite regulator brand.

Now youve tried that and eliminated it as a possible cause, pulsing
regulators seem to indicate something is sticking inside.

Regulators are relatively simple inside, the pressure increase screw
outside pushes down onto a spring thats one side of the diaphragm,
on the other side is a valve sometime a cone in a depression or a flat
plate.

Id be inclined to ask a car mechanic who has good experience with
taking stuff to bits to dismantle it to have a look nd see.

It could be a bit of dirt thats got stuck in the valve when you
changed tanks.

One should always crack open tanks whenyou first get them full to
blow out any dust in the threaded hole where the regulator screws in.

To dismantle them yourself youd need some big spanners or wrenches!
and a decent bench vice.

Its most unusual for the diaphram to fail.

Hello Joy,

do not light the gas while youare bleeding. Smith Company said it
was too dangerous. Cindy Eid had to call Smith Co. and get
confirmation. 

Ordinarily, when I’m finished at the soldering bench for the day, I
light the torch, turn off the gas at the tank, watch the flame burn
down and out, let it bleed the remaining small amount of gas without
the flame and then turn down the (air) pressure, all the while
ventilating through a long hose that brings any fumes out of the
studio. I use a Smith torch and a two-part regulator (gas, air).

I’m a little concerned about the extra ‘free’ gas being in my studio
if I bleed the hose the way you described above. And if I am
ventilating while bleeding, the gas will enter the long vent hose to
exit the studio (that’s just the way it is in my studio). Is there
any reason to be concerned about this unburned gas, either in the
studio or the hose (if it hasn’t fully exited the hose)?

Thank,
Linda Kaye-Moses

I have been nursing a faulty regulator for about a month. Pressure
raises while torch is not on. Pressure falls while torch is on. So, I
brought it to the welding shop in Watertown, Sd where they carry the
Smith regulator. They informed me that Smith no longer allows the
diaphragm replacement due to warranty issues. I ended up buying a new
one. I still have the old one which is actually far from old. It is
about 5 years old and no longer under warranty.

I bought this from Rio and just actually bought it 2 years ago.
Obviously it had been in stock a long time before it was sold to me.
I feel as though it should last longer than 2 years. I have shut it
down properly every single time I used it. Grrrr.

Jean