Transformer oil discharge and nitrogen injection fire extinguishing device SW-BPD

During the operation of oil immersed power transformers, regardless of the sustained high temperature generated by the iron core or the sudden short-term high temperature caused by high-energy discharge due to internal arcs such as short-circuit overvoltage, as long as the temperature of the transformer oil can be made greater than 400 ℃, combustible gases may decompose, resulting in an increase in internal pressure of the transformer. The internal overpressure of the transformer causes its weak parts (such as transformer porcelain bushings, body welds, explosion-proof ports, etc.) to break into cracks, causing transformer oil and combustible gases to spray out of the cracks together. The mixture of sprayed transformer oil and combustible gases will ignite or even explode when it comes into contact with air, causing significant losses.

Our company has developed the SW-BPD type transformer oil discharge and nitrogen injection fire extinguishing device to address the characteristics of oil immersed power transformer faults. It is the first fire extinguishing device in China to use a specially designed solenoid valve mechanism and has passed national certification as a new type of device. The new device eliminates the traditional electromagnetic mechanism and heavy hammer linkage operating mechanism, and adopts a brand new electromechanical integrated operating mechanism, which is accurate and reliable in action. Effectively avoiding the phenomenon of heavy hammer jamming and misoperation caused by corrosion of the electromagnetic mechanism pull rod track, and effectively compensating for the defect of traditional products that cannot continue to be used after action and must replace the components of the device itself, reducing the maintenance and upkeep costs of the product and extending its service life.

2、 Product Technical Features

2.1 Outstanding features:

1) Prioritize prevention and combine prevention with elimination. It can effectively prevent fires caused by the rupture of oil immersed transformers, avoid significant losses, and facilitate the safe operation of transformers;

2) Fire extinguishing media such as water or foam are not used, and fire drainage design and related facilities are exempted;

3) This facility is an environmentally friendly product and does not cause any pollution to the environment or the transformer itself;

4) Low cost, simple operation and management, and easy maintenance;

5) This device is powered by a DC power supply and operates stably; After the signal and logic relationship are established, the electromagnetic mechanism is activated to immediately extinguish the fire, eliminating the possibility of misoperation and ensuring a short extinguishing time;

6) Limit the scope of damage caused by internal faults and reduce the losses caused by transformer fires;

7) Compact structure, easy to install;

8) Not limited by geographical environment such as water sources, will not freeze or block; Effectively solved the passive situation of "water determines location" caused by the lack of water resources in the three northern regions of China, including North China, Northwest China, and Northeast China.

2.2 Technical Parameters

Nitrogen cylinder capacity: 40L, 63L;

The nominal pressure of nitrogen in the nitrogen cylinder is 13-15Mpa (20 ℃);

Internal oil discharge pipeline diameter: φ 100mm; φ125mm; φ150mm；

Diameter of nitrogen injection pipeline: 25mm;

灭火箱重量： 230～240kg；

Fire extinguishing box control circuit voltage: DC220 ± 5% V, the sum of the floating values of each harmonic component is less than 1% of the DC current;

Effective nitrogen injection time ≥ 10-30 minutes.

The operating temperature of the detector is 93 ± 2 ℃;

Working environment temperature: -40 ℃~60 ℃, altitude ≤ 2000 meters.

2.3 Startup conditions

2.3.1 Fire prevention and extinguishing status

When the control center receives the following signals:

Temperature detector signal;

Heavy gas relay signal;

Circuit breaker trip signal (optional);

The control center confirms that there is a significant fire hazard with the transformer and issues an audible and visual alarm. If the system is in automatic mode, the fire cabinet will be activated, oil and pressure will be drained, and nitrogen will be injected to extinguish the fire.

2.3.2 Explosion proof pressure relief

When the control center receives the following signals

Action signal of overpressure detection system;

Heavy gas relay signal;

Circuit breaker trip signal (optional);

The control center confirms that there is a significant risk of explosion and fire in the transformer, and issues an audible and visual alarm. If the system is in automatic mode, the fire cabinet will be activated, oil and pressure will be drained, and nitrogen will be injected to extinguish the fire. The pressure action value of the device should be higher than the pressure action value of the pressure release valve of the main transformer. The specific value is determined in the transformer ordering technical agreement, and the recommended value is 8-10 KPa.

2.3.3 Manual Control

If the system is in manual mode, when an explosion or fire hazard is detected, the fire cabinet can be manually activated to drain oil and pressure, and nitrogen can be injected to extinguish the fire. Manual start can also include a circuit breaker trip signal, which means that manual control can only be achieved after the circuit breaker trips.

3、 Ordering Notice

1. Please provide the capacity of the oil immersed transformer;

2. Please confirm the number of fire detectors;

3. Please provide the diameter requirements for the oil discharge pipe;

4. Please provide the usage environment and altitude.