The sulfur hexafluoride series refers to a full line of medium-voltage switching and protection devices that use SF6 gas as the insulation and arc-quenching medium. Thanks to its exceptional dielectric strength and fast arc interruption capability, SF6 enables highly compact, fully enclosed switchgear designs that have become a standard solution for urban, industrial and renewable energy distribution networks.

Sulfur hexafluoride is a synthetic, colorless, odorless and non-flammable gas with a dielectric strength approximately 2.5 times that of air at atmospheric pressure. When an electric arc forms during switching operations, SF6 gas molecules rapidly absorb arc energy and recombine, extinguishing the arc within a few milliseconds. This property allows SF6 devices to interrupt high fault currents safely within a sealed metal enclosure, with no exposed live parts and no risk of arc flash to personnel.

The sulfur hexafluoride series covers several core product categories for different distribution functions. SF6 load break switches are used for routine load switching and circuit isolation in distribution networks. SF6 circuit breakers provide full short-circuit protection for transformers and feeders, interrupting fault currents up to tens of kiloamperes. SF6 ring main units (RMUs) are compact, all-in-one cabinets that integrate incoming switches, outgoing breakers and busbars, widely used in secondary distribution networks. Gas-insulated switchgear (GIS) is a higher-voltage, fully assembled substation solution that packages all primary components inside SF6-filled metal enclosures.

Compared to traditional air-insulated switchgear, the SF6 series offers three key advantages. First is its extremely compact footprint — gas insulation reduces equipment size by 60–80% compared to air-insulated equivalents, making it ideal for urban underground substations, box-type substations and sites with limited space. Second is high operational safety: the fully sealed structure eliminates exposure to live components, and prevents dust, moisture and small animals from causing faults. Third is low maintenance requirements: sealed gas chambers require almost no routine maintenance for 10–20 years, significantly reducing long-term operational costs.

SF6 series equipment is widely used in urban power distribution networks, industrial plant substations, commercial building power supply systems, wind and solar farm collector stations, and railway electrification systems. It is especially preferred in densely populated areas, indoor installations and harsh outdoor environments where reliability and space efficiency are critical.

When specifying SF6 series products, buyers should pay attention to three key factors. First, confirm rated voltage, rated current and short-circuit breaking capacity to match system parameters. Second, verify gas leakage rate indicators — high-quality products maintain an annual leakage rate below 0.1%. Third, establish standardized gas management practices: SF6 is a potent greenhouse gas, so used gas must be recovered, recycled and purified instead of being vented to the atmosphere. Professional installation and maintenance by certified personnel are also required to ensure long-term safe and compliant operation.

We supply a complete range of SF6 series switchgear products covering 12kV to 40.5kV voltage levels, including load break switches, ring main units and circuit breakers. Contact our engineering team for datasheets, project configuration and quotation.