Connecting Pressure Regulators

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Connecting Pressure Regulators

Improper installation and use of pressure regulators can be dangerous and may cause damage to the regulators. Proper installation and use of pressure regulators and tanks is safe. Before connecting pressure regulators to their respective tanks, position the tanks in a safe location away from flame and out of walk ways. The fuel tank, usually propane, must be in its upright position sitting on its intended bottom. Fuel gas is usually pressurized to a liquid, as is propane, butane and MAPP gas. The tank valve must be positioned above the liquid, in the gas, for the pressure regulator to work properly. The oxygen tank can be positioned in any position. It is usually best to stand it up. Before removing any safety caps, secure the tanks to a wall or the work bench, if it is stable enough to give proper support.

Remove the caps from the tanks and connect the pressure regulators. Connect the torch to the output side of the pressure regulators with proper hoses. Propane, butane or MAPP gas must only be used with a Grade T hose. Regular welding type Grade R or Grade RM hose, which is fine for acetylene, will rot with propane, butane or MAPP gas. Do not use acetylene as a fuel gas. It does not work well with glass and lampworking torches are not designed to use it. Be sure that there is not any oil, grease or debris in or around the tank valves, hoses or on any part of the pressure regulators. Grease and oil are explosive in the presence of oxygen. Debris on the fittings will not allow for a proper air tight seal. The thread pattern on the oxygen tank valve is right handed. The thread pattern on the fuel tank is left handed. Left handed threads are indicated by a notch around the fastening nut on the pressure regulator and the hose fittings. The fittings on both pressure regulators and the hoses are flair type fittings and only require moderate tightening. All fittings are made of brass and are easily destroyed if the wrong tools are used to tighten them. Only use the proper size open end wrenches or quality adjustable jaw (Crescent style) wrenches. Vise Grips or Channel Lock style wrenches will quickly destroy the fittings and will not tighten them properly. It is not necessary to use a thread sealer and should not be used as it can actually cause a leak if it gets into the seat area of the connection. Test for leaks with soapy water.

Before opening the tank valves it is important that the pressure adjusting handles are backed off to a zero pressure delivery. This is done by turning the handle counterclockwise until the resistance of the handle turning becomes easy. It is alright if the handle comes off the pressure regulator. Just screw it back on one full turn. If the pressure adjusting handle is not backed off when the tank valve is opened, the fast inrush of gas may damage the diaphragm inside the pressure regulator. Check that all torches connected to the regulators are off. Before opening the tank valve, stand next to the tank, positioning the tank valve between you and the pressure regulator. If the pressure regulator is damaged it may blow off the tank when the tank valve is opened. Standing behind the tank valve is the safest location. The oxygen cylinder is under high pressure and uses a special double seat valve. The valve only seats air tight when it is fully closed or fully open. Any position in-between may slowly leak oxygen from around the valve stem. Open the oxygen tank valve slowly for the first turn, then fully and firmly. The fuel tank is usually under much less pressure and uses a different kind of valve. Open this valve slowly for the first turn, then only to one or two turns. This makes it faster and easier to turn off the propane tank's valve in an emergency situation. Turn the pressure adjusting knob clockwise to allow gas to pass through the pressure regulator. The more the handle is turned, the greater the delivery pressure will be. The pressure gauge closest to the tank valve indicates the tank pressure. The other pressure gauge indicates delivery pressure to the torch. To reduce delivery pressure, turn the adjusting knob counterclockwise. The delivery pressure gauge will not indicate a lower pressure until the pressure is relieved on the output side of the pressure regulator. You can do this by having the torch running while turning the handle counter clockwise. To shut down the system, close the tank valves, burn off the pressurized gas in both gas lines by lighting the touch. As the flame goes out turn off the torch, back off the pressure adjusting handles as described earlier.

The best pressure to use for the health of the regulators is between 20 and 25 pounds for the oxygen and 10 to 15 pounds for the fuel gas. Using these pressure settings will keep the pressure regulators performing better and have a longer life. However, some glasses are hyper sensitive to flame chemistry and can show signs of reducing at these higher than necessary pressures. In this case you may want to choose different pressure settings that are likely lower. Every torch has its own optimum pressure settings. Many torches give suggested pressure settings that are lower than what is stated here. These pressures are listed as a range with the lower pressure being the minimum to establish a proper flame and the higher pressure being the most the torch needs to obtain the largest proper flame it can produce. The lower pressure is typically so low that it usually produces so small a flame as to be unsatisfactory for lampworking. Supplying higher pressure does not increase gas consumption. The actual oxygen and fuel gas consumption that the torch operates on is what you manually set using the torch's valves. Some propane pressure regulators have a red danger zone on the delivery pressure gauge. This only applies when the pressure regulator is used with acetylene. Disregard it when using propane, butane or MAPP gas.

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