Do Oil-Filled Transformers Need a Containment Pan?

In the power system, oil-filled transformers are very common equipment. The insulating oil filled inside plays a key role in insulation and heat dissipation. However, insulating oil is a flammable substance. Under certain circumstances, it is very likely to cause fires or even explosions and other serious safety accidents. Therefore, whether to equip oil-filled transformers with containment vessel has become a highly anticipated issue.

Hidden safety risks of oil-filled transformers

1. Explosion risk

If an oil-filled transformer fails and arcing or high temperature is generated, which may cause the insulating oil to decompose rapidly and release a large amount of gas. In this way, the pressure inside the transformer will rise sharply. Once the pressure exceeds the bearing limit of the transformer shell, an explosion will occur. The impact caused by the explosion is not only the damage to the transformer itself, but also great harm to the surrounding personnel and equipment.

2. Fire risk

During operation, the oil-filled transformer may cause the insulating oil temperature to rise due to overload, short circuit, poor contact and other conditions. When the temperature reaches the flash point of the oil, a fire may be caused. Since the insulating oil is fluid, once a fire occurs, the fire can easily spread rapidly, thereby posing a serious threat to surrounding equipment and buildings.

Functions of containment vessel

1. Environmental protection

Once the insulating oil burns or leaks, it will pollute the environment. The containment vessel can effectively prevent the insulating oil from leaking into the surrounding environment, avoid soil, water sources, etc. from being polluted, and thus reduce the damage to the ecological environment.

2. Explosion protection

When an oil-filled transformer explodes, the containment vessel can withstand a certain pressure, play a buffering role, and reduce the degree of damage to the surrounding environment caused by the explosion shock wave. At the same time, the containment vessel can also prevent transformer fragments from flying around, effectively ensuring the safety of surrounding personnel and equipment.

3. Fire protection

The containment vessel can effectively prevent the spread of fire in oil-filled transformers. When a fire occurs in a transformer, the containment vessel can limit the flames and high-temperature gases to a certain range to prevent them from spreading to surrounding equipment and buildings. This buys firefighters time to extinguish the fire, thereby reducing the losses caused by the fire.

Situations where containment vessel is required

1. Oil-filled transformers near crowded places

If oil-filled transformers are installed near crowded places such as shopping malls, schools, and hospitals, once an accident occurs, it is very likely to cause a large number of casualties. Setting up a containment vessel can reduce the risk of injury to personnel in accidents and create safer conditions for the evacuation and rescue of personnel.

2. Oil-filled transformers installed indoors

For oil-filled transformers installed indoors, since the indoor space is relatively closed, once a fire or explosion occurs, the consequences will be more serious. The containment vessel can limit the impact of the accident to the room, prevent the fire and explosion shock wave from spreading to other areas, and protect the safety of personnel and equipment in the building. For example, in the distribution rooms of some large factories, oil-filled transformers are usually equipped with containment vessel.

3. Areas with high environmental requirements

In areas with high environmental requirements such as nature reserves and water source protection areas, once the insulating oil of oil-filled transformers leaks, it may have a serious impact on the environment. The containment vessel can prevent the leakage of insulating oil, thereby protecting the local ecological environment.