The anti-skid protection, coal piling protection, off-track protection, emergency stop device along the belt conveyor
, smoke protection, anti-tear protection, under-voltage protection, over-current protection should be connected to the belt conveyor control circuit or the main circuit, and all protection should be sensitive and reliable.
Overtemperature automatic sprinkler protection should be connected to the belt conveyor electronic control circuit, when the temperature exceeds the limit, it can automatically open the water source to cool down, and alarm stop.
(1) Protection installation requirements
1. Anti-slip protection
1.1 Installation Requirements:
Anti-skid protection of belt conveyor should be installed above the return belt of belt conveyor. When the fixed belt conveyor is installed, it should be installed between the head unloading roller and the driving roller; When the distance between the two driving drums is far, it can also be installed between the two driving drums; The belt conveyor used in other places should be installed in the return belt close to the head; Simple belt (Note: mining face with 800mm and below telescopic belt, the same below) anti-skid protection should be set on the side of the changing drum, and the distance from the side of the drum should not exceed 50mm. When anti-skid protection is installed, the sensor should be fixed on the big frame of the belt head with a standard bracket, and it is strictly prohibited to use iron wire or other items tied and fixed.
1.2 Protection Features:
When the conveyor belt speed within 10s is within the range of (50%~70%)Ve(Ve is rated belt speed), the conveyor belt speed is less than or equal to 50%, and the conveyor belt speed is greater than or equal to 110%Ve, the anti-skid protection should be alarmed, and the operation of the belt conveyor should be suspended at the same time. The normal start and stop speed changes of the belt conveyor. Anti-skid protection device shall not have protective action.
2, pile coal protection
2.1 Installation Requirements:
2.1.1 When two belt conveyors are lapped, the coal stacking protection sensor shall be hung in front of the unloading roller; The horizontal position of the sensor contact should be directly above the coal drop point, and the distance from the highest point of the upper belt surface of the lower belt should not be more than 500mm, and the hanging height should not be higher than the lower edge of the unloading roller. The installation should take into account the condition of the sprinkler device to prevent the wrong action of coal piling protection.
2.1.2 Using the coal chute tape, the coal pile protection sensor contacts can be installed on one side of the unloading drum, the hanging height shall not be higher than the lower edge of the unloading drum, and the horizontal position shall not be more than 200mm away from the outer edge of the unloading drum.
2.1.3 When the belt is directly bonded with the coal bunker, a coal pile protection sensor shall be installed at the full position of the coal bunker and 500mm above the coal drop point of the coal chaser respectively, and the two coal pile protection sensors shall be sensitive and reliable.
2.1.4 For the location of transfer by mining car or other means, the local full load of mining car or coal receiving facility is taken as the reference point, and the distance between the contact of coal pile protection sensor and the reference point should be between 200 and 300mm.
2.1.5 The coal pile protection control line should be led down vertically from the roadway roof, and the sensor contacts should be hung vertically and fixed reliably. It is strictly prohibited to swing with the air flow, so as to avoid wrong action of protection.
2.1.6 When iron remover or other facilities are installed on the head of belt conveyor, which affects the installation of coal pile protection sensor, special processing bracket shall be installed to ensure that the sensor is firmly fixed.
2.2 Protection Features:
When the coal stacking protection device continuously monitors the coal level exceeding the preset value within 2s, it should give early warning and stop the operation of the belt conveyor. The coal pile protection device which is protected by changing the sensor deflection Angle or operating stroke requires no more than 9.8N.
3, run off protection
3.1 Installation Requirements:
The deviation protection of fixed belt conveyor should be used in pairs, and one set should be installed at the nose and tail, 10~15m away from the nose and tail. When the slope of the belt conveyor changes, one set should be installed at the slope changing position; Simple belt deviation protection only needs to be installed in the head of a group. The special bracket is fixed on the big frame or longitudinal beam of the belt conveyor to protect the deviation of the belt surface of the belt conveyor.
3.2 Protection Features
3.2.1 When the conveyor belt deviation exceeds the edge of the idler by 20mm(for example, the belt conveyor using triple rollers exceeds 70mm), the deviation protection device shall give an alarm.
3.2.2 When the conveyor belt in operation exceeds the idler by 20mm(for example, the belt conveyor using triple rollers exceeds 70mm), after a delay of 5~15s, the deviation protection device should operate reliably and stop the operation of the belt conveyor.
3.2.3 For the deviation protection device such as the contact deviation sensor, the positive force required by the protection action on the center point of the deviation sensor is 20~100N.
4. Smoke protection
4.1 Installation Requirements:
The smoke protection for a belt conveyor should be installed directly above the conveyor at 10 to 15m downwind of the driving drum of the belt conveyor head. The smoke sensor should be hung vertically, no more than 300mm away from the top plate. When the conveyor is driven by multiple drums, the drum near the head should prevail.
4.2 Protection Features:
When the smoke concentration reaches 1.5% within 2 consecutive seconds, the smoke protection shall give an alarm and stop the operation of the belt conveyor. At the same time, the automatic sprinkler shall be started to sprinkle water to cool down.
5, tear protection
5.1 Installation Requirements:
The main belt conveyor shall install anti-tear protection 10~15m to the head direction (when the belt machine is driven by the head) below the coal drop point of the belt. Anti-tear protection is installed between the upper and lower layers of conveyor belt,
The protection mode is piezoelectric or traction wire rope type anti-tear protection, the installation should be processed standard bracket, the anti-tear protection is fixed on the conveyor rail, by the upper belt direction.
5.2 Protection Features:
When the running belt is torn longitudinally, the anti-tear protection should alarm and stop the operation of the belt conveyor at the same time.
6, over temperature automatic sprinkler protection
6.1 Installation Requirements:
Thermocouple induction type overtemperature sprinkler protection sensor should be fixed on the main drive drum block (bearing seat), simple belt conveyor overtemperature sprinkler protection sensor installed in the main drive frame background reducer side top end cover bolt hole; When the infrared sensor is used, the sensor launching hole should be directly detected at the bearing end cover (tile seat) of the main driving drum, and the distance between the sensor and the main driving drum is 300~500mm. When there are two sets of driving devices, the temperature sensor is installed on the end cover tile seat of the main drum bearing farther away from the unloading drum.
6.2 Protection Features:
At the temperature measuring point, when the temperature exceeds the specified amount, the automatic overtemperature sprinkler should alarm, and at the same time, the automatic sprinkler can be started (the automatic overtemperature sprinkler of belt conveyor is fixed on the inclined support of the main roller in the background of the main drive frame with a U-shaped card, and the nozzle is facing the main roller in the background), spraying water to cool down. Belts with two sets of drives, sprinklers must be mounted on the same drive drum as the overtemperature protection.
7, undervoltage protection
When the power grid voltage is lower than 65% of the rated voltage, the magnetic starter or feed switch controlling the belt conveyor should operate reliably, cut off the power supply of the conveyor, and stop the operation of the conveyor.
8, over current protection
The magnetic starter or feed switch of the belt conveyor shall be controlled. When the running current of the conveyor motor exceeds the setting value of the control switch, it shall act reliably, cut off the power supply of the conveyor, and suspend the operation of the conveyor.
9. Anti-slide braking device
9.1 Installation Requirements:
Down-running belt conveyors in inclined roadways (with an average dip Angle of more than 8°) must be equipped with sliding brake devices. The brake device can be installed between the motor of the conveyor and the reducer, or separately installed in the input shaft end of the reducer or the two-shaft extension end (simple belt conveyor can take effective measures to prevent the belt from sliding).
9.2 Protection Features:
When cutting off the power supply of the belt conveyor, the brake device should operate reliably, and can timely brake the belt conveyor roller running, to prevent the conveyor from sliding.
10, check brake device
10.1 Installation requirements: An upward belt conveyor in a inclined roadway (with an average dip Angle of more than 8°) must be equipped with a check brake device. Ratchet type check brake device can be installed on the reducer of the conveyor; Or the plug belt type check brake device is installed between the driving drum and the belt.
10.2 Protection Features:
When the power supply of the conveyor is cut off, the check brake device should be reliable, and can stop the operation of the conveyor in time to prevent the reverse sliding operation of the conveyor.