Chapter1 properties of sf6 free download as powerpoint presentation. Sf6 circuit breakers construction, types and working. Sf6 gas is electonegitive tends to attract the free electrons and has the arc quenching property. The general properties of sf 6 gas and its sf 6 byproducts are presented. Sulfur hexafluoride may cause severe eye burns leading to permanent damage.
Guidance is given for working with sf 6 gas and sf 6 filled equipment under normal and. Remove containers from area of fire if safe to do so. It is chemically inert, gaseous even at low temperature, non flammable, non toxic, non corrosive. It is commonly used in medium and highvoltage electrical equipment as an electrical insulator, arcquenching and cooling medium.
Jan 02, 2019 this page describes history of sf6, manufacturing process of sf6 gas, chemical properties and electrical properties of sf6 gas. Breathing sulfur hexafluoride can irritate the nose and throat. Sf6 properties, and use in mv and hv switchgear semantic scholar. Sulfur hexafluoride an overview sciencedirect topics. The unit can be operated when the gauge is in the green or greenandyellow stripe zone but it must be refilled if the. To request a quote or for more information about air products, please fill out the form below, and an air products representative will contact you shortly. 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. Sf 6 sulphur hexafluoride gas has excellent dielectric, arc quenching, chemical and other physical properties which have proved its superiority over other arc quenching mediums such as oil or air. Sf6 is one of the heaviest known gases with a density about 5 times the density of air under similar conditions. Sulfur hexafluoride can affect you when breathed in. Sf6 is used in electrical equipment because of its dielectric strength, excellent insulating properties and its arcsuppression capabilities. Sf6, the most potent greenhouse gas in existence, was banned for all applications in the eu in 2014 except in the electricity industry. This document describes reclamations management and safe handling procedures for sf6 gas. If the normal oxygen content of air is reduced from 21 percent to less than percent, suffocation can occur without warning.
This 35minute dvd describes the properties of sf6 and its byproducts, personal protection, safe handling of the gas and its byproducts, and cleanup and disposal of sf6 byproducts. A reference equation of state for the thermodynamic properties of sulfur hexafluoride sf6 for temperatures from the melting line to 625 k and pressures up to 150 mpa article mar 2009. As the demand for this gas was increasing, many manufacturers in europe and america started producing sf 6 gas in large scale, during that time. During 1960, using of sulfur hexafluoride gas in high voltage switchgear became popular. Thermodynamic properties of sulfur hexafluoride request pdf. The important properties of sf6 circuit breaker are. Sf6 does not exist in a liquid state unless pressurised. May 21, 2018 sf6, the most potent greenhouse gas in existence, was banned for all applications in the eu in 2014 except in the electricity industry. Sulfur hexafluoride sf 6, which is the preferred gas for use in gasinsulated switchgear circuit breakers, disconnect switches, etc. Sulfur hexafluoride isalso an efficient infrared ir absorber, and due to its chemical inertness is not rapidly removed from the earths atmosphere. I learned the alumina is too far off for a smart decision.
Breakdown characteristics of sf6cf4 mixtures in test. Sf6 is an electronegative gas, which determines its. In addition, if not handled properly, sf6 can present certain hazards. I have listed below few advantages which make sf6 desirable for being used in cb. Sulfur hexafluoride sf6 gas properties electrical study. Breakdown voltage of compressed sulfur hexafluoride sf6. Sf6 gas properties and handling dvd alexander publications. General properties of sulphur hexafluoride sf6 fluorocarbons. Sulphur hexafluoride sf6 circuit breaker a circuit breaker in which sf 6 under pressure gas is used to extinguish the arc is called sf 6 circuit breaker. Handling and use of sulfur hexafluoride gas page 4 of 8 v. Also go through disadvantage so that you may know the safety precautions too. Sf6 basic physical properties chemical formula sf6 molecular. The effects of sf 6 on the environment are discussed. Sf6 is an extremely stable, nonflammable and highly electronegative gas with excellent dielectric properties.
A brief history of the use of sf 6 in switchgear is given. Sulfur hexafluoride can irritate the skin causing a rash or burning feeling on contact. The environmental problems caused by greenhouse gases have received unprecedented attention. Sf 6 gas has used the wide range of application in the field of high voltage insulation, such as gasinsulated switchgear and gas insulating transmission line1. During operation of sf6 circuit breaker, this highly compressed gas is released through the arc in the breaker and collected to a relatively lowpressure reservoir and then it is pumped back to the highpressure reservoir for reutilizing. To compare early visual and anatomical outcomes after either sulfur hexafluoride sf 6 or perfluoropropane c 3 f 8 tamponade for macular hole repair methods.
Wear selfcontained breathing or airsupplied respirator. Sulfur hexafluoride gas sf6 properties heavy, chemically inert, non toxic no poisonous effect on the human body but decomposition products are poisonous color less and odor less it is gaseous at normal room temperature and pressure density is about 6. Its combined chemical, thermal and electrical properties allow many advantages to be achieved. Sulphur hexafluoride sf 6 is an excellent dielectric gas for high voltage applications. C c c c c f f f f f f f f f f o materials insulation gas leakage and gas losses energy losses 0 20 40 60 80 100 co2 equivalent emissions % 145 kv gis with c5 pfk gas mixture 145 kv gis with sf 6. Sulfur hexafluoride sf 6 is an inorganic, colorless, odorless, nonflammable, nontoxic but extremely potent greenhouse gas, and an excellent electrical insulator.
Comparison of partial discharges in sf6 and fluoronitrileco2. Sf6 circuit breaker types and operation of sf6 circuit. However, sf 6 is a greenhouse gas and there are lifecycle management costs associated with its use. The wavelength shift during the application of a current pulse has been studied in detail. For decades, the unique properties of sulfur hexafluoride sf 6 have made it popular as an insulation and switching medium for electrical switchgear. Commonly used within the electrical industry as an insulating medium, the properties of sf6 gas also make it ideal for use within ophthalmology. Sulphur hexafluoride gas sf6 is employed as insulation in all parts of the installation, and in the circuitbreaker also for arcquenching. Onsite fire brigades must comply with osha 29 cfr 1910.
Sulfur hexafluoride 100 2551624 ingredient name % cas number there are no additional ingredients present which, within the current knowledge of the supplier and in the. So i learned, that if i am trying to make a decision as to whether to reject new gas, or discardrefurb gas in use or accept the new gas or verify the gas in use is within certain thresholds, the chilled mirror really makes it easy to make that decision. In the beginning, sf6 gas was only used for the insulating purpose in the electrical system. Breakdown characteristics of sf6cf4 mixtures in test chamber. Sf6 primary use is in the electrical industry as a gaseous dielectric medium for various voltage circuit breakers, switchgear and other electrical equipment, often replacing oil filled circuit breakers ocbs that can contain harmful pcbs. Vista underground distribution switchgear has been carefully designed to provide extremely reliable gas seals. Pdf electrical strength analysis of sf6 gas circuit breaker element. Sf6 is an electronegative gas, its dielectric strength at atmospheric pressure is approximately three times that of air. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Properties of sf6 7 minutes describes the physical characteristics of sf6. A colorless, odorless, nontoxic liquified gas purity. Pdf this paper addresses the problems, connected with calculation of the. In the year of 1937, general electrical company first realized that sf 6 gas i.
The paper also provides the recommendations for change sf6 circuit breaker design. A colorless, odorless gas with no warning properties. The reason for the exemption, writes nicholas ottersbach, researcher, that there was no viable alternative. Sf6alternative gases for application in gasinsulated. Sulfur hexafluoride gas sf6 properties instrumentation tools. Some sf6 properties from astm standard specification for sulfur hexafluoride, d 2472 81, are shown in the table below.
As discussed in the section of this issue relative to characteristic properties, the sf6 gas in the switch is largely free of degradation over the entire life of the switch. In the dry etching process, control of process time, process temperature as well as selection of the reactive ion mixture, are very important. Sulfur hexafluoride sf6 is an inorganic, colorless, odorless, nonflammable, extremely potent greenhouse gas, and an excellent electrical insulator. These properties are particularly suitable for applications in power transmission and distribution equipment.
Pressure pressure is a measure of the force exerted by a gas per unit area. A brief history of the use of sf6 in switchgear is given. Sulfur hexafluoride gas sf6 properties engineering. Test the gas for arc byproducts if there is a possibility of an internal failure. Sulfur hexafluoride sf 6 versus perfluoropropane c 3 f. Byproducts of sulfur hexafluoride sf6 use in the electric.
Measurable properties of gases what we mean when we talk about the amount of gas present usually expressed in moles or the volume it occupies is fairly clear. Handling of sulfur hexafluoride gas central facilities. Sulfur hexafluoride gas is dielectric and cooling gas used in switchgear system. Sulfur hexafluoride gas sf6 properties engineering tutorial. The dielectric and other physical and chemical properties related to its lack of reactivity have led to the extensive use of sf 6 as an insulating medium in switching equipment e. The human health and environmental dangers of sf 6 gasfilled switchgear by lisa sattler blackburn innovative switchgear solutions, inc. Sf 6 or sulfur hexafluoride gas molecules are combined by one sulfur and six fluorine atoms. Sf6 properties, and use in mv and hv switchgear contents 1 introduction 1. Here sf6 gas was compressed and stored in a highpressure reservoir. Sf6 is an inert gas and does not sustain combustion. The switch also includes a viewing window or port, so that the position of the switch blades can be visibly verified as required by certain us regulations and codes. Pure sf6 is of a low order of toxicity, but may act as an asphyxiant if oxygen is reduced to below 16%, as indicated by paleness and possible cyanosis blue skin. This gas was first realized in the year of 1900 in the laboratories of.
Section c removal of sulfur hexafluoride gas from inservice equipment. Sulfur hexafluoride sf6 is an inorganic, colorless, odorless, and nonflammable gas. But according to ottersbach that is no longer the case. Avoid leakage of a liquefied gas such as sf6 onto water or. Combination of free electrons with molecules produces heavy and big ions, which have very low mobility. No action shall be taken involving any personal risk or without suitable training.
Sf 6 has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. Specification of technical grade sulfur hexafluoride sf6 for use in electrical equipment other common reference standards. It can, however, exclude oxygen and cause suffocation. The interrupting alternatives to sf6 gas which could be considered for retrofitting into existing switchgear under laboratory conditions are g3 and vacuum technology. Pdf dielectric breakdown properties of hot sf6 gas contaminated. Sf6 shows little change in vapor pressure over a wide temperature range and is a soft gas. Sulfur hexafluoride sf6 safety data sheet sds p4657. Direct contact with the liquefied material, compressed gas, may cause frostbite injury. Comparison of partial discharges in sf 6 and fluoronitrileco2 gas mixtures boya zhang, yang cao university of connecticut, usa. The general properties of sf6 gas and its sf6 byproducts are presented. Insulation characteristics of sulfur hexafluoride sf6. Sulfur hexafluoride safety data sheet p4657 this sds conforms to u. Sf6 is odorless, colorless, tasteless, and nontoxic in its pure state. Sulfur hexafluoride and the electric power industry.
Sf 6 gas has used the wide range of application in the field of high voltage insulation, such as gas insulated switchgear and gas insulating transmission line1. Apr 28, 2016 sulfur hexafluoride gas sf6 properties heavy, chemically inert, non toxic no poisonous effect on the human body but decomposition products are poisonous color less and odor less it is gaseous at normal room temperature and pressure density is about 6. All sf 6 gas shall be obtained through a central facility. General properties of sulphur hexafluoride sf6 identity.
Further tips for getting the right reading and pumpback issues. Pdf the dielectric breakdown properties of hot sf6 gas during the dielectric recovery phase play an important role in understanding gas breakdown. Jan 02, 2019 here sf6 gas was compressed and stored in a highpressure reservoir. Most reactive ions that are created from chemical dry etching are tetrafluoromethane cf 4, sulfur hexafluoride sf6, chlorine gas cl 2, or fluorine gas f 2 41. Sf6 gas possesses excellent dielectric properties and high degree of chemical stability. Sulphur hexafluoride sf6 is a synthetic gas comprising of one sulphur and six fluorine atoms. Because of this main reason sf6 gas is used for arc quenching and insulation medium in circuit breakers. Key properties of the gas are that it is extremely chemically stable and has a relatively high density.
Proc of the 3rd international conference on properties and applications of. For some years, abb has been conducting research into alternatives with lower environmental. Sf 6 is an excellent dielectric gas for high voltage applications. Sulfur hexafluoride sf6 is an inorganic, colorless, odorless, nonflammable, nontoxic but. Gas pressure is indicated by the internal pressure gauge. However, the concepts of pressure and temperature deserve a little more discussion. The human health and environmental dangers of sf 6 gas filled switchgear by lisa sattler blackburn innovative switchgear solutions, inc. Physical and chemical properties of sulphur hexafluoride. Release of sf6 gas into the atmosphere during maintenance work or an accident must be reduced, tracked, and reported to the epa. In life, in business, in the ordinary course of doing things, there is a certain level of risk that comes with just existing.
The designated central facility is responsible for maintaining a log of all sf 6 gas. Sf6 properties, and use in mv and hv switchgear electrical. Sf6 gas or sulfur hexafluoride gas properties electrical4u. Also these main technical view point must be considered in alternative gases. Sf6 has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. Recently, a high voltage and insulation group at tokyo electric power company completed a series of experiments to study the breakdown characteristics.
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