SF6 Transformer



Demand for effective space utilization is becoming increasingly stronger

as a result of grade advancement of commercial/industrial activities and

urban life styles.

Concurrently, city construction facilities including buildings, underground shopping
areas, traffic systems, and public structures are becoming larger in size and gaining in
the degree of complications. Since such facilities immensely contribute to improving
the efficiency of urban activities, the current trend indicates the possibility of further
expansion in the future.

On the other hand, accidents involving outbreaks of extensive fire and

other troubles are occasionally occurring in these large-sized urban facilities,
resulting in the creation of public voices demanding improved fire or accident
preventive measures.

These construction facilities of cities represent high-valued social assets. However,

since a great number of citizens utilize such .facilities day after day, it is quite essential

to provide effective means to eliminate outbreaks of fire.

To achieve this purpose, it is important to install modern fire-fighting

systems capable of coping with various causes of fire. At the same time,

Basically it is most important to eliminate the possible causes of fire.


The SF6 gas-insulated Transformers are designed to ideally satisfy

Non flammability-ensuring plans of power reception and transformation systems
 installed in these urban facilities. Since no oil for insulation is used, these Transformers
can completely free structures or adjacent rivers from oil contamination during new
 installation work or system operation. In other words, the SF6 gas-insulated

Transformers qualify themselves as truly "non flammability-ensuring equipment"

 usable for power systems required to prevent fires or accidents and eliminate pollution.



The SF6 gas-insulated Transformers offer excellent insulation and cooling
characteristics and thermal stability. Additionally, these Transformers possess
the following features resulting from containing the active parts in a tank sealed
with nonflammable, harmless, and odorless SF6 gas.

   1. High-level stability

Even should the actual Transformer develop an accident, or should a fire
 break out on the installation environment, combustion or an explosion will not occur.

Since all live parts are housed in grounded metal cases, maintenance and inspection

can be achieved easily and safely.

    2. Outstanding accident preventive characteristics Nonflammable structure
employing no insulation oil contributes to minimizing the scope of associated

accident-preventive facilities such as fireproof walls, fire-fighting equipment, or oil tanks.  

    3. Compactness of substation

By directly coupling with gas-insulated Switchgear, substation space can be minimized
 as the result of compact facilities.

    4. Simplified maintenance and long service life

Because the Transformers are completely sealed in housing cases, no contact exists

with exterior atmospheric air, thereby eliminating problems of degradation or contamination

triggered by moisture or dust accumulation. Constant enveloping of components with inactive,
dry SF6 gas results in minimizing aging deterioration of insulating materials and
prolonging Transformer service life.

    5. Easy, clean installation

SF6 gas can be quickly sealed into the Transformer tank from a cylinder.
Installation work never contaminates surrounding areas, and ensures maintenance

of a clean environment.

     6. Ideal for high voltage systems

By increasing the seal pressure, SF6 gas Transformers offer insulation performance

 comparable to that of oil-insulated types, being ideal for high voltages of 22 kV to 154 kV.


The SF6 gas-insulated Transformers are suitable for the following applications:

  • Locations where safety against fire is essential Buildings such as hotels,
    department stores, schools, and hospitals Underground shopping areas,
    underground substations Sites close to residential areas, factories, chemical plants

  • Locations where prevention of environment pollution is specifically
    demanded Water supply source zones, residential quarters, seaside
    areas Water treatment stations

  • Locations where exposure exists to high-level moisture or dust accumulation
    Inside tunnels, industrial zones