Sulfur hexafluoride Solvay
Sulfur hexafluoride Solvay is usually used as arc quenching and insulating medium for high and medium voltage switchgear systems. The favourable electrotechnical, chemical and physical characteristics of the gas have considerably influenced the development of the switchgear technology. SF6 is an alternative to other conventional insulating and quenching media such as e.g. oil, and air. The use of SF6 gas considerably increases, in some applications, the efficient utilisation of resources in energy transmission and distribution with respect to technology, finances and personnel. At the same time SF6 in comparison to oil reduces the risk of hazard (e.g. fire, explosion) to personnel and environment. An overall evaluation considering all ecological, economic, safety and technological aspects has proven that SF6 is still an excellent choice as insulating medium. The existing SF6 technology in the field of energy transmission and distribution is the result of decades of optimisation and contributes essentially to the further development of the economically efficient power distribution.
Sulfur hexafluoride Solvay is used in different types of electrical switchgear:
• Modern, state of the art, High Voltage and Extra High Voltage switching devices (e.g. circuit breakers) use SF6 as an arc-quenching medium, almost exclusively. More integrated solutions, like the Gas Insulated Switchgear (GIS) use the gas not only as arc-quenching medium but as insulation as well.
• In the Medium Voltage range circuit breakers, switches, etc., using different quenching media including SF6, are normally installed inside a metal enclosure (traditional metal-enclosed switchgear).
Sulfur hexafluoride Solvay advantagies:
• Low operating energy for the switching devices.
• No risk of fire.
• Not toxic hazard.
• Favourable ergonomic conditions, due to the small volume and relatively light weight.
• Easy choice of optimal installation site.
• Recommended use in severe climatic conditions (sea shore, heavy industrial pollution, etc.)
• Long service life.
|Vapor Pressure, 21.1 °C||MPa||2.9|
|Heat capacity at constant pressure||kJ/(mol.K)||0.0977|
|Solubility in water||vol/vol||0.07|
|Purity, %||≥ 99.9.|
|Air, ppm||≤ 50|
|SF4, ppm||≤ 10|
|H2O, ppm||≤ 0.65|
|Mineral oil, ppm||≤ 1|
|Acidity, ppm||≤ 0.3|
|Hydrolysablefl uorides, ppm||≤ 1|
• steel cylinders, 50kg;
• steel drums, 600kg.