Its unique properties and characteristics make it an excellent insulating gas and gaseous dielectric within the electric utility industry. Sf6 is used in electrical equipment because of its dielectric strength, excellent insulating properties and its arcsuppression capabilities. Sf6 gas, used as a dielectric medium in circuit breakers and switchgear, has a global warming potential 24 000 times greater than co2 and some of its byproducts were used as chemical weapons in world war i. Excellent insulation properties, strong arc quenching abilities, and high dielectric strength nonflammable and nontoxic to humans colorless and odorless. Request pdf sf6 gas properties sf6 gas properties find, read and cite all the research you need on researchgate. It was used for the first time as insulating material, in the united states about 1935. Dielectric gases are used as electrical insulators in high voltage applications, e. Health and environmental dangers of sf6filled switchgear. Jeff spoljarick from abb and dave smithberger from first energy, presented on the best management practices of sf6 gas handling. Pdf insulation and molecular properties of alternative. The general properties of sf6 gas and its sf6 byproducts are presented. Sf6 a gas with unusual properties solvays sulphur hexafluoride is a non toxic, inert, insulating and cooling gas of high dielectric strength and thermal stabil ity. However, its global warming potential gwp index and staying. It is able to stay in vapor form at normal operating temperatures up to about 250 psi.
Sulphur hexafluoride its properties and use as a gaseous. Sulfur hexafluoride sf6 or sulphur hexafluoride british spelling, is an extremely potent and. Prior to removal of gas, check the gas compartment and associated devices for. Return all empty cylinders and appropriate logs to the central facility. Spark discharge characteristics of various sf6based binary. At merlin gerin, the research work, concerning the use of sf6 gas for insulation and circuitbreaking was initiated around 1955. In 1953, the americans discovered its properties for extinguishingtheelectric arc. Sf 6 gas excellent for insulating and arc quenching substantial properties of sulfur hexafluoride at a glance. Sulfur hexafluoride safety data sheet p4657 this sds conforms to u. A material to which a gas, liquid or dissolved solid will adhere to the surface of. Combination of free electrons with molecules produces heavy and big ions, which have very low mobility. The lifting field of a free conducting particle fcp situated on a dielectric coated electrode in compressed sf6 gas is calculated based on two different particle charging mechanismspartial.
The designated central facility is responsible for maintaining a log of all sf 6 gas. A dielectric gas, or insulating gas, is a dielectric material in gaseous state. In life, in business, in the ordinary course of doing things, there is a certain level of risk. Ternary sf6 gas mixtures possessing higher dielectric strength than sf6 can 2. Sf6 sulphur hexafluoride gas has excellent dielectric, arc quenching, chemical and other physical properties and has proved its superiority over other arc quenching mediums such as oil or air. Physical properties sf6 is 5 times heavier than air and is one of the heaviest known manmade gases. It was used for the first time as insulating material,in the united states about 1935. The structural parameters, density of states and frontier. These applications include medical testing, laboratorybased research and development, and the analysis of sf6 gas present in medium and high voltage gas insulated electrical equipment. Sf6 circuit breakers construction, types and working. It should be noted that the time to breakthrough for any glove.
Handling of sulfur hexafluoride gas central facilities. The effects of sf 6 on the environment are discussed. In this paper, the gas sensing properties of a new planar 2d material indium triphosphide inp 3 had been proposed and studied towards four types of sf 6 decomposed gases h 2 s, so 2, sof 2 and so 2 f 2 by dft methods. Sf6 gas has excellent electrically insulating characteristics and thermal properties.
Sulfur hexafluoride gas has strong electronegativity and insulating properties, making them a better option than air and oil circuit. A liquefied gas packaged under pressure, sf 6 s thermal stability and high dielectric strength provide excellent insulating and cooling properties. Sf6 is a combination of sulfur and fluorine its first synthesis was realized in 1900 by french researchers of the pharmaceutical faculty of paris. Handling and use of sulfur hexafluoride gas page 6 of 8 b record date, location, and equipment nomenclature on cylinder log. Sf6 is a dielectric gas with high dielectric strength which is used in high voltage applications related to power equipment technology.
Removal of sulfur hexafluoride gas from inservice equipment. Sulfur hexafluoride sf6 safety data sheet sds p4657. A colorless, odorless gas with no warning properties. The detection of sf 6 decomposed gases is essential link for the fault diagnosis of gas insulated switchgear gis. Oct 23, 2020 due to these unique properties of this gas, sf6 circuit breaker is used in a complete range of medium voltage and high voltage electrical power system. Breakdown voltage of compressed sulfur hexafluoride sf6. Safety data sheet ghs product identifier other means of identification product type section 1. Relevant identified uses of the substance or mixture and uses advised against use of the substancemixture. Sf6 is chemically inert, nonflammable, and nontoxic. The effects of sf6 on the environment are discussed. Sulfur hexafluoride is a nonflammable, colorless, odorless, tasteless, nontoxic and relatively unreactive gas which has been described quite often as an inert gas 42. Basic properties of compounds used in electrical insulation. Sulfur hexafluoride is a synthetic gas used as insulator for electrical equipment breakdown potential three times larger than air, and as a fluorine source for edging in the electronics industry.
Insulation and molecular properties of alternative gases to sf6. Guidelines for the checking and treatment of sulfur. Due to leaking of sf6 in air, it will mix insufficiently with air, and will retain itself neartoground levels. Routine sf 6 gas testing forms an integral part of commissioning and maintenance procedures. Alternative environmentally friendly insulating gases for sf6 mdpi. The gas handling system for the mp accelerator and a. Also available as a complete and portable kit, allowing users to carry all of the equipment that they need within a heavyduty ip66 case. It is commonly used in medium and highvoltage electrical equipment as an electrical. Sf6 properties, and use in mv and hv switchgear electrical. Guide for sulfur hexafluoride sf6 gas handling for high voltage over vac equipment iec 60376. Guidance is given for working with sf 6 gas and sf 6 filled equipment under normal and. It is incombustible, nontoxic, odourless, chemically inert with arcquenching properties 3 to 4 times better than air at the same pressure. Recently, a high voltage and insulation group at tokyo electric power company completed a series of experiments to study the breakdown characteristics.
These circuit breakers are available for the voltage ranges from 33kv to 800 kv and even more. Details of the supplier of the safety data sheet praxair, inc. Guidance is given for working with sf6 gas and sf6 filled equipment under normal and abnormal conditions of. Sf6 exhibits 25 times better heat transfer properties than air. The sf6 circuit breaker is mainly divided into three types. Sf6 gas is colorless, odorless gas with a vapor density five times that of air. May 28, 2014 dos and donts of sf6 gas handling author. A brief history of the use of sf6 in switchgear is given.
Sep 20, 2011 sf6 is an electronegative gas, its dielectric strength at atmospheric pressure is approximately three times that of air. Sulfur hexafluoride and the electric power industry. A circuit breaker in which sf6 under pressure gas is used to extinguish the arc is called sf6 circuit breaker. Arced sf6 sf6 gas which has been subject to operations where breaking fault current. The general properties of sf 6 gas and its sf 6 byproducts are presented. Sulfur hexafluoride isalso an efficient infrared ir absorber, and due to its chemical inertness is not rapidly removed from the earths atmosphere. A study on dielectric strength and insulation property of sf6n2. Feb 20, 2021 sf6 circuit breaker is an extinguisher that uses sulfur hexafluoride gas to cool and quench the arc. The concentration of sf6 in the atmosphere is currently relatively low, leading to a contribution to the total anthropogenic published by copernicus publications on behalf of the european geosciences union. Pdf the dielectric breakdown properties of hot sf6 gas during the dielectric recovery phase play an important role in understanding gas breakdown.
Exposure controls appropriate engineering controls. Both of these latter properties make sf 6 a potent greenhouse gas, although due to its chemical inertness and the absence of chlorine atoms in the sf6 molecule it is benign with re. All sf 6 gas shall be obtained through a central facility. Its density at 20c and 0,1 mpa that is one atmosphere is 6.
Specification of technical grade sulfur hexafluoride sf6 for use in electrical equipment other common reference standards. Sulfur hexafluoride sf 6 or sulphur hexafluoride british spelling, is an extremely potent and persistent greenhouse gas that is primarily utilized as an electrical insulator and arc suppressant. An introduction to gas insulated electrical substations. Equipment chambers for sf6 usually contain adsorbers to adsorb arced byproducts. Is the end coming for sulfur hexafluoride, the most. Pdf on the detection and control of metallic particle. Airline hydraulics products and solutions to power your ideas. However, even if sf 6 switchgears are safe for the environment, the sf 6 insulating gas has potential significant environmental impacts if it leaks into the atmosphere. Sf6 basic physical properties chemical formula sf6 molecular. Indeed, as sf6 is used for several decades, its insulating properties and consequently the theoretical rules to design products regarding their dielectric withstand are now well known.
Although sf6 gas is not detrimental to the ozone layer, it is a highly potent greenhouse gas. Handling and use of sulfur hexafluoride gas page 4 of 8 v. An outline will be given of the physical and electrical properties, and a method of detecting and removing the corro sive breakdown products will be described. Sulfur hexafluoride an overview sciencedirect topics. Sulfur hexafluoride 2551624 acgih acgih tlvtwa ppm ppm usa osha osha pel twa mgm. It is a nonflammable, nontoxic gas, which decomposes at 750 k. A brief history of the use of sf 6 in switchgear is given. A gas insulated substation gis is a high voltage substation in which the major conducting structures are contained within a sealed environment with a dielectric gas known as sf6, or sulfur hexafluoride gas as the insulating medium. Excellent insulation properties, strong arc quenching abilities, and high dielectric strength nonflammable and nontoxic to humans colorless and odorless under high temperature conditions 350 f, sf. It is particularly suitable for application in both highvoltage and mediumhigh volt. Indeed sf 6 is one of the six gases listed in the kyoto protocol, with a global. An illustration of some of sulfur hexafluoride gas properties.
In 1953, the americans discovered its properties for extinguishing the. Its main purpose is to prevent or rapidly quench electric discharges. Adsorption properties of inp3 monolayer toward sf6. Sf 6 gas quality must be maintained for its useful properties to remain effective. From the figure, it is seen that the ncharacteristics. Sf6 gas or sulfur hexafluoride gas properties electrical4u. It is 23,900 times more effective at trapping infrared radiation than carbon monoxide and is stable in the atmosphere for some 3,200 years. Sf6 shows little change in vapor pressure over a wide temperature range and is a soft gas. Some sf6 properties from astm standard specification for sulfur hexafluoride, d 2472 81, are shown in the table below.
The excellent dielectric properties of sf6 are due to the electronegative character of its molecule. Equations for thermodynamic properties have been cited from oda et al. Sf6 is an extremely stable, nonflammable and highly electronegative gas with excellent dielectric properties. Sf6 circuit breaker advantages disadvantages applications. It has a pronounced tendency to capture free electrons forming. Pdf dielectric breakdown properties of hot sf6 gas contaminated. The concentration of sf6 in the atmosphere is currently relatively low, leading to a contribution to the total anthropogenic published by copernicus publications on behalf of. Sf6 a gas with unusual properties solvays sulphur hexafluoride is a non toxic, inert, insulating and cooling gas of high dielectric strength and thermal stability.
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