Coal Mine Safety Regulations

Article 145 stipulates: When a shaft equipped with a belt conveyor is also used as an intake air shaft, an automatic alarm and fire extinguishing system must be installed, and fire-fighting pipelines must be laid.

Product Introduction:

The underground automatic explosion isolation device in coal mines uses ultra-fine dry powder as the extinguishing medium. The driving device is purely mechanical, capable of bidirectional and remote start. The trigger is unaffected by underground power outages, forming a system of automatic explosion isolation devices underground. All installed automatic explosion isolation devices can be monitored from the mine dispatch room, achieving unmanned management. Verified by the Safety Standard Center's simulation experiments, it can quickly extinguish explosion flames, reduce fire zone temperature, and provide stable and reliable explosion isolation.

The device is fixed above the roadway roof using anchor bolts, and the layout and installation quantity are selected according to the roadway conditions. The shock wave receiver faces the direction of the shock wave and flame spread caused by the explosion. The shock wave reaches the receiver before the flame, triggering the device to spray the explosion isolation medium, forming a high-efficiency mist explosion isolation area. This mist explosion isolation medium can suspend long enough to wait for the flame and extinguish it, preventing explosion spread.

System Composition:

The device system consists of an underground ring network, substation, intrinsically safe power supply, automatic explosion isolation device, pressure gauge, carbon monoxide sensor, smoke sensor, flame sensor, methane sensor, flame sensor, pressure sensor, and other sensors.

Using automatic detection, when various sensors detect abnormal parameters such as shock waves and flames, the trigger device is automatically controlled to activate. The powder outlet of the explosion suppressor is fan-shaped, using longitudinal injection to automatically spray powder, forming a high-efficiency mist explosion isolation area to block flames.

The mine automatic explosion isolation system uses ultra-fine ABC dry powder extinguishing agent as the extinguishing medium. The explosion suppressor has a short powder spraying delay and fast mist formation. This mist explosion isolation medium can suspend long enough to block flames, preventing flame spread.

The device's drive is purely mechanical, with sensitive response, short delay, wide coverage, and high explosion suppression efficiency. It uses a block structure for simple installation, maintenance, and convenient use, with low device height.

Data from the installation site uses a transmitter with a high-performance silicon piezoresistive pressure core, integrated with a microprocessor and signal conversion circuit. It converts sensor pressure signals into RS485 digital signals, uploads them to the surface via the network, and the monitoring substation is responsible for data collection and processing.

Product Features:

1. Sensitive response, easy and quick installation, maintenance, and servicing.
2. The 25KG model has a low design height, occupying little roadway space, especially suitable for low-height roadway mines.
3. The driving device is purely mechanical or electrical, capable of bidirectional and remote start.
4. All installed automatic explosion isolation devices' working status can be monitored in the dispatch room, achieving abnormal parameter alarms for the isolation devices and roadway parameters.
5. Achieves unmanned management.

Main Technical Parameters:

1. Power Supply

1. Rated operating voltage: AC 127V;
2. Rated operating current: ≤400 mA;
    

2. RS485 Communication

1. Channels: 1; number of sensors connected: 32 (expandable);
2. Transmission mode: half-duplex, RS-485 transmission mode;
3. Transmission rate: 2400bps; operating voltage peak-to-peak: ≤6V;
4. Maximum transmission distance: 2km (using MHYVP1*2 (7/0.52mm) mine communication cable)
    

3. Optical Fiber Communication

1. Number of ports: 2; transmission mode: 1310nm single-mode dual-fiber;
2. Transmission rate: 100Mbps;
3. Optical emission power: (-8～0)dBm;
4. Receiving sensitivity: -25dBm;
5. Maximum transmission distance: 20km (using MGTSV optical cable, attenuation coefficient 0.5dBm/km).
    

4. Ethernet Communication

1. Number of ports: 2;
2. Transmission mode: TCP/IP protocol;
3. Transmission rate: 10/100Mbps adaptive;
4. Signal operating voltage peak-to-peak: ≤6V;
5. Maximum transmission distance: 100m (using MHYVRP type cable, single-core cross-sectional area 0.75mm2).

5. Switch Signal Output (Non-Intrinsically Safe)

1. Number of signal channels: 1;
2. Signal type: high and low level signals;
3. Signal voltage: high level 24V, low level 0V.

6. Intrinsically Safe Parameters:

Um: 140V AC; RS485 signal: Uo: 5.6V, Io: 280mA, Co: 50μF, Lo: 0.2mH

7. Automatic Explosion Isolation Device Parameters

1. Extinguishing powder weight: 25kg/35kg/40kg
2. High-pressure gas chamber volume: 3.78L
3. Gas chamber pressure value: 12±1MPa
4. Opening pressure: ≥0.02MPa
5. Overall device dimensions: 7360×444×525mm
6. Spray delay time: <15ms
7. Main unit weight: 100kg
8. Total equipment weight: 128kg