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Old 2005-06-24, 7:05am
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Dale M. Dale M. is offline
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Join Date: Jun 10, 2005
Location: A Little Bit West of Yosemite Valley
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Default About Oxygen and Fuel Regulators.

A Little About Oxygen and Fuel Regulators.

By Dale Meisenheimer

Hopefully this will explain a little about oxygen and fuel regulators as applied to lampworking glass.

First a warning (caps are intentional but I am not yelling - this is important).

AS YOU UNPACK YOUR NEW REGULATOR YOU WILL BE TEMPTED TO TURN THE KNOB OR "T'" HANDLE ALL THE WAY IN (CLOCKWISE) IN BELIEF YOU ARE TURNING KNOB OR "T" HANDLE ALL THE WAY TO THE "OFF" POSITION. --THIS IS NOT TRUE.-- YOU WILL BE TURNING THE REGULATOR ALL THE WAY "ON " AND BY PUTTING IT DOWN TIGHT (CLOCKWISE) YOU MAY DAMAGE REGULATOR AND NEED TO HAVE IT REPAIRED BEFORE YOU EVER GET TO USE IT. THE CORRECT WAY TO TURN REGULATOR OFF OR REDUCE GAS FLOW IS TURNING KNOB OR "T" HANDLE ALL THE WAY TO THE LEFT (COUNTER CLOCKWISE) TILL ALL RESISTANCE ON KNOB OR "T" BAR HANDLE IS RELEASED.

Ok….

Looking at your new regulator you will see that it is either a brass or chrome in color and/or may have red or green paint on part or all of regulator body. The significance of the red and green color is the red regulator is the fuel regulator and the green regulator is the oxygen regulator.

Most regulators are designed with the snout that connects to tank on the right side, two gauges on top of the regulator body and a "line" connection or left (or lower left ) side of body, and a knob or "T" handle on knob in center of regulator body.

First lets look at the tank connector (snout) on right side of body. These connectors are also industry standard, if they don't fit your tank, you have WRONG tank. The oxygen regulator has a female threaded nut that screws into the outside of the valve body of the oxygen tank. This is a "right hand" thread connection. This connection is a high pressure connection, and should thread together smoothly with no obstruction. A moderate pressure applied with a wrench should tighten this connection and it should be leak free. If you can not get a proper seal here there is a problem with connection, take things apart to see what is going on. Bad threads, dirt in connection, whatever.

Same goes for fuel regulator, only it will be a male connector that goes in the inside of valve body on fuel tank (propane in most cases). Again this is a mechanical fit and needs a moderate pressure applied with wrench to be leak free. The difference here is this is a LEFT HAND (counter clockwise) thread. See the small grooves cut midway into connection nut, this signifies it is a left hand thread. Also the "groove" cut into all the fuel fittings for hoses and torches signify left-hand threads ( counter clockwise)

When connecting regulators to tanks DO NOT use any sort of Teflon tape or thread sealant, this is dangerous. These connections are designed to be metal to metal only. If tank will not seal there is a problem with either a defective valve or dirt or some soft of obstruction in connection. IF you can not get tank to seal, take it back to supplier and explain the problem and ask for exchange.

The tank to regulator connection should be check for leaks with a "leak detection" fluid. Do not use soapy water or an oil based fluid to do this. OIL and PURE OXYGEN when put together can cause SPONTANEOUS COMBUSTION or an EXPLOSION. It's a documented fact. If you don't believe me look it up in any standard reference source. There is commercially available leak detection fluids that are oxygen safe on market.

Moving around regulator body the first gauge on right is the "supply" or "tank" pressure gauge. A oxygen regulator gauge will probably read from "0" to "2500" psi. This will tell you what the pressure is in your oxygen tank as you use your system. A typical full oxygen tank will read about 2000 psi. On the fuel regulator this gauge will typically read from "0" to "200" psi. A propane tank will read about "100 - 120" psi continuously till tank is almost empty (this is the nature of LP gas).

The gauge on the left is the low pressure gauge and this will be the working pressure of the "line out" of the regulator to torch. A oxygen regulator typically has a "0" to "100" psi (a gauge reading 0-50 may be more desirable). The outlet gauge on the fuel regulator may read "0'" to "60" psi (a gauge reading 0-30 may be more desirable). These gauges will tell you what the working pressure of the oxygen and fuel you are sending to your torch is regulated to. Gauges with lower "max" readings on output side tend to be more accurate when working with low pressures. When looking at regulators to purchase, this may be a consideration.

At left of regulator is a threaded male fitting which is the "line outlet" going to torch. On the oxygen regulator this is a right hand thread fitting (clockwise) and the green hose that connects to torch connects to this fitting. On fuel regulator this connection is a left hand thread (counter clockwise) and the red hose to torch connects to this fitting. You can verify that because the nut on red hose has the groove in it indicating left hand thread.

In the center of regulator body is the "T" handle or a knob. This where you adjust the pressure of the oxygen or fuel going to torch. The "T" handle or knob on both oxygen and fuel regulator operate the same way. With the "T" handle or knob unscrewed all the way to the left (counter clockwise) there should be no gas flow, the regulator has effectively shut off the gas or oxygen. First you should open the valves on oxygen and fuel tanks and check for leaks with approved leak detection fluid. Fix any leaks as they are found. Take note of tank readings, this is clue to when you will need more fuel or oxygen. If all is well, open the oxygen valve on torch and adjust oxygen regulator by turning "T" handle or knob to the right (clockwise) till you get desired reading (for our example we will use 8 psi). Close valve on torch, notice reading on gauge will climb up a bit to maybe 10-12 psi. This is normal. Opening valve on torch again should allow pressure to drop and maintain at 8 psi again. Close torch valve. Do the same for fuel regulator. Open valve at torch, and set fuel pressure to 4 psi ( again for our example) by turning handle or knob to right (clockwise). Close valve at torch. Reading on fuel gauge may climb to 6-7 psi. this normal. Opening valve on torch should allow gauge reading to drop to 4 psi. Turn off valve. Your pressure reading will probably be different on regulated side as you find what combination of fuel/oxygen pressures work best for you.

Regulators operate in temperatures for below freezing to sever desert heat with out any problems. Regulators also take very little actual care, but there are some things to consider. If regulator is out side it should be protected from the weather. A simple plastic bucket turned upside down over regulator and tank will protect regulator and tank valve from wind and rain. And whether regulator is inside or outside try to keep it as dust free as possible. And DO NOT use oils or lubricants of any kind on any threaded parts of fitting for regulators or tank valves – REMEMBER FIRE/EXPLOSION HAZARD. When using tools to tighten or loosed the regulators to/from tanks be sure to use a wrench that fits the regulator nut properly. A nut with corners rounded off (from using pliers or improper tool) will be miserable to work with and the problem will only get worse as time goes on.

OK… Now that you have had a successful day at the torch, its time to shut down the torch and close tank valves and bleed the system.

A. Close the valves on fuel and oxygen tanks.

B. Open oxygen valve on torch and watch pressure drop on oxygen regulator gauges.

C. After both gauges on oxygen regulator are at ZERO back off the "T" handle or knob of oxygen regulator three or four turns (COUNTER-clockwise).

D. Close oxygen valve on torch.

E. Open fuel valve on torch, and watch pressure drop on fuel regulator gauges

F. After both gauges on fuel regulator are at ZERO back off the "T" handle or knob of fuel regulator three or four turns (COUNTER-clockwise).

G. Close fuel valve on torch.

Bleeding regulators and removing tension on adjustment knobs or "T" handle keeps regulators from being damages when there is a rush of high pressure fuel or oxygen in to regulator next time you turn the tank valves on.

You may want to observe gauges on regulators for a few moments to see that they do not climb back up a bit indicating tank valves are not complete closed down.

Oxygen tanks and propane tanks have a "safety" anti leak seal on tank valves that require the tank valves to be all the way open to seal any possible leak around valve "stem". It's also a safety thing to have valve all the way open. In case of a emergency there is only one way tank valve will turn and that is closed. This keeps you from accidentally opening valve more in the confusion of the emergency.

A more expansive amount of information on regulators, fuel and oxygen can be found in James Kervins book " More than you ever wanted to know about Glass Beadmaking". It is one of the must have technical books on working glass that one should have in their library.

A bit about different regulator types….

Do not confuse a two GAUGE regulator with a two STAGE regulator.

These are two different regulator features. A single gauge regulator is simply a two gauge regulator that has the high pressure gauge removed and gauge port plugged and you will not be able to see tank pressures ( unless it is specifically designed with one gauge only - typically not a regulator from welding application). This is a bit of a cost savings and with propane the pressure will be constant (nature of LP gas) until you are probably almost out of propane.

A two stage regulator has two separate diaphragm arrangements internally and usually steps the high tank pressures to a intermediate pressure then to the regulated out put pressure. Two stage regulators are ultimate in pressure control and are more precise than a single stage regulator. Also cost is quite a bit more. A single stage regulator has only one diaphragm in its design and has to regulate the tanks high pressure to the regulated output pressure in a single step. these regulators are less expensive and not as sensitive to adjustment, but quite capable of operation your torch with the degree of precision required and at a significant coat savings over a 2 stage regulator.

Also more information on regulators can be found online at:

http://www.arrowsprings.com/html/con...egulators.html

Remember to also keep a fire extinguisher always handy, and check it occasionally to be sure it is ready if needed.

Hoping you have a well regulated adventure.

NOTE: This document is copyright © 2003-2005 by Dale Meisenheimer.
This document may not be reproduced on any other website or forum without express written permission by the author.


Rev 6-24-05
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Last edited by Dale M.; 2005-06-24 at 7:08am.
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