Points : Air inleakage detection Definition Air inleakage know how to be inferred beginning an increase in the air concentration in the gases drawn inedible by the air- injector system. It is frequently associated with an increase in condenser rear pressure. Note that there is always a minimum air inleakage that cannot be eliminated. Westinghouse Electric Corp. used to recommend to air inleakage levels be apprehended to 1 ft3min per 100 MW of generation capacity, but new minima are known in the ASME and HEI standards. An increase in the dissolved oxygen concentration in the condensate can too indicate that air is leaking into the suction of the condensate pumps under the condenser hot well. Tracer gases are used to locate the source of air inleakage, two of the most common being helium and sulfur Hexafluoride (SF6). SF6 be first used effectively as an airborne tracer in atmospheric research and demonstrated its larger sensitivity as a tracer gas. Sulfur hexafluoride, discovered in 1900, is a colorless, tasteless, and incombustible gas which is practically inert from a chemical and biological standpoint. It does not react with water, caustic potash, or strong acids and be able to be heated to 500°C with no decomposing. Two of its common uses within the utility industry are for arc suppression in high voltage circuit breakers and the insulation of electric cables. SF6 as well has many other uses, such as etching silicon in the semiconductor industry, increasing the wet strength of craft paper and protecting molten magnesium as of oxidation in the magnesium industry. The fundamental property of SF6 is that it can be detect in very low concentrations- as low as 1 part per 10 billion (0.1 ppb)-compared with the lowly detectable concentration of helium of 1 part per million above background. It was later found that on-line injections utilizing SF6 also allowed leaks as little as one gallon per day to exist detected.
Maintenance - Air inleakage detection
Points : Air inleakage detection Definition Air inleakage know how to be inferred beginning an increase in the air concentration in the gases drawn inedible by the air- injector system. It is frequently associated with an increase in condenser rear pressure. Note that there is always a minimum air inleakage that cannot be eliminated. Westinghouse Electric Corp. used to recommend to air inleakage levels be apprehended to 1 ft3min per 100 MW of generation capacity, but new minima are known in the ASME and HEI standards. An increase in the dissolved oxygen concentration in the condensate can too indicate that air is leaking into the suction of the condensate pumps under the condenser hot well. Tracer gases are used to locate the source of air inleakage, two of the most common being helium and sulfur Hexafluoride (SF6). SF6 be first used effectively as an airborne tracer in atmospheric research and demonstrated its larger sensitivity as a tracer gas. Sulfur hexafluoride, discovered in 1900, is a colorless, tasteless, and incombustible gas which is practically inert from a chemical and biological standpoint. It does not react with water, caustic potash, or strong acids and be able to be heated to 500°C with no decomposing. Two of its common uses within the utility industry are for arc suppression in high voltage circuit breakers and the insulation of electric cables. SF6 as well has many other uses, such as etching silicon in the semiconductor industry, increasing the wet strength of craft paper and protecting molten magnesium as of oxidation in the magnesium industry. The fundamental property of SF6 is that it can be detect in very low concentrations- as low as 1 part per 10 billion (0.1 ppb)-compared with the lowly detectable concentration of helium of 1 part per million above background. It was later found that on-line injections utilizing SF6 also allowed leaks as little as one gallon per day to exist detected.
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