Oxyfuel Welding test questions and answers 2023 update(verified for accuracy)

What is the purpose of a pressure regulator? All pressure regulators reduce the high cylinder or system pressure to the proper lower working pressure What may result if a pressure regulator is not used on the type of has or pressure range for which it was designed? it can cause fire or an explosion Describe how a single stage regulator operates As the diaphragm is moved the small high pressure valve is opened allowing more gas to flow into the regulator.The gas pressure cancels the spring pressure and the diaphragm returns back to its original position closing the high pressure valve Is the torch pressure always the same as the working gauge pressure? No because the torch pressure is always less than the pressure shown on the working pressure gauge Why does high pressure gauge on a regulator not always indicate the amount of gas in the cylinder? Cylinder contain liquefied gases How does the operation of a safety relief valve differ from the operation of a safety disc valve? is made up of a small back held tightly against a seat by a spring. Difference between argon cylinder valve and carbon dioxide cylinder valve? Argon cylinder is a female fitting Carbon dioxide is a male fitting Regulator creep is a high pressure valve seats that leak or a rising pressure who can repair regulators? only a trained repair technicians why must the pressure be released from a regulator when work is finished? to prevent damage to the diaphragm , gauges and adjusting spring why are combination welding and cutting torches considered to be more versatile? because it can be attached quickly to the same torch body what is the advantage of using an injector type mixing chamber? the injector works by passing the oxygen through a venture which creates a vacuum to pull the fuel has in and then mixes the gases together what should be done to the valve packing if the valve knob does not turn freely after it has been tightened to stop a leak? replace the valve packing what may happen to a tip seat if it is incorrectly tightened? may result in damage to the torch body or the tip what can happen to a tip if it is excessively cleaned with a tip cleaner? tip cleaner tends to ream the orifice making it to large what is the difference between a reverse flow valve and a flashback arrestor? reverse flow valve is to present gases from accidentally flowing thru the torch and into the wrong hose Flashback arrestor stop the flame of a flashback what are Siamese hose? Siamese hoses are hoses that are molded together as one piece why must the pressure be bled off hoses when work is complete? the hoses can explode if they are not bled off Difference between backfire and a flashback? Backfire: occurs when the flame goes out with a loud snap or pop Flashback: occurs when the flame is burning inside the tip, torch , hose or regulator why is a neutral flame the most commonly used oxyacetylene flame used? because it adds nothing to the metal what properties should be a good leak detecting solution have? it most flow freely into the small joints, cracks, and other areas that may leak and produce good quality without leaving a flim why must the oxygen cylinder valve be opened all the way to the top? because the product will not leak out into the atmosphere how long should hoses be purged? long enough to allow the hose to be completely purged of air what should be done with cylinders that have leaking valve stems? turn off the cylinder valve before tightening any leaking connections how should the spark lighter be held to light a torch hold the spark lighter near the end of the tip but not covering the tip once the torch is lit. why must the acetylene flow be increased until the flame stops smoking before the oxygen is turned on for adjustment? keeps the tip cool what type of piping can be used for manifold system all gases except acetylene