Technical parameters of anti-corrosion runaway switch for thermal power plants

Deviation switch FGK-H32B/TK（Corrosion-resistant and wear-resistant）It is a protective device used to detect the degree of belt deviation during the operation of a belt conveyor, issue an alarm, and automatically trigger an emergency stop. Using a deviation switch can prevent damage to expensive conveyor belts and prevent further industrial accidents and personal injuries. The two-stage deviation switch is a protective device in the safe operation and transportation system, widely used in steel plants, thermal power plants, cement plants, chemical plants, ports, etc.

During the operation of the conveyor, when the belt deviates and comes into contact with the switch roller, the roller rotates on its own. If the deviation continues to increase, the roller will be squeezed and displaced. The level 1 switch signal is used for alarm. If this signal is connected to the running adjustment device, automatic adjustment of running deviation can be achieved without stopping the machine. The level 2 switch signal is used for shutdown. By connecting this signal to the control circuit, automatic shutdown can be achieved under severe deviation conditions. After troubleshooting, when the tape leaves the vertical roller and operates normally, the vertical roller can automatically reset.

Deviation switch, also known as anti deviation switch. Used to detect the deviation phenomenon during the operation of belt conveyors, output alarm or shutdown signals according to the actual deviation of the belt, which can effectively prevent accidents caused by belt deviation. This series of deviation switches has a two-level action function. Level 1 action is used for alarm, and level 2 action is used for automatic shutdown. During the operation of the tape machine, when the tape deviates and comes into contact with the vertical roller of this switch, the vertical roller rotates on its own. If the deviation continues to increase, the squeezing vertical roller will deviate.

Technical parameters:

Working voltage: 24~380V

Insulation resistance:>500M Ω

Output signal: Passive switch signal

Environmental temperature: -20 ℃~+60 ℃

Environmental humidity:<90%

Weight: 2.5Kg

Protection level: IP67

Reset method: automatic reset

Response time:<2Ms

Control contact capacity: 1A-10A

Action force: 50 ± 10N

Working Principle:

When an emergency occurs on the conveyor belt, the steel wire rope attached to the swing arm can be pulled to rotate the swing arm, which in turn drives the internal cam of the conveyor belt and senses the micro switch to issue a stop signal.

Regarding the installation and debugging steps of the two-stage belt deviation switch:

Fix the deviation switch on the bracket. The vertical roller should be perpendicular to the plane of the conveyor belt edge, and the conveyor belt edge should be located at 1/3 of the height of the vertical roller. Then weld it to the tape rack; The distance between the vertical roller and the edge of the tape is 50-100mm. The tape is located at the bottom one-third of the vertical roller; Three pairs of deviation switches can be installed every 100m of tape. The number of two-stage deviation switches installed should be determined based on the length, type, and layout of the conveyor. Generally, it should be set at the active roller, passive roller, and intermediate position of the conveyor. For longer conveyors, one pair can be set every 30-35 meters at the middle position. The two-stage deviation switch should be connected to the conveyor frame through an installation bracket. The switch bracket should be firmly welded to the conveyor frame, and then the deviation switch should be bolted to the bracket. Wiring: The output line of the two-stage deviation switch is a four core cable. Users can wire according to their own requirements.

What should I do if the conveyor belt deviates

What should I do if the conveyor belt deviates? As we all know, if the conveyor belt deviates to the left, adjust the left side of the guide pulley under the conveyor belt backward, or adjust the right side of the guide pulley forward.

Similarly, if the conveyor belt deviates to the right, adjust the right side of the guide pulley under the conveyor belt backward, or adjust the left side of the guide pulley forward.

But recently our unit encountered a problem, which is that the conveyor belt sometimes deviates to the left and sometimes deviates to the right. And we use stainless steel conveyor belts with wrapped rubber roller shafts. If the roller shaft is turned into a slightly waist drum shape, the middle of the stainless steel will be uneven due to stretching. How should this situation be resolved

One of the most common faults during the operation of a belt conveyor is the deviation of the conveyor belt. There are various reasons for deviation, mainly due to low installation accuracy and poor daily maintenance.

When the conveyor belt is running normally, the belt speed should not be lower than 95% of the roller speed. If the friction between the drum and the conveyor belt is not sufficient, the conveyor belt is prone to slipping. There are many reasons that can cause insufficient friction between the roller and the conveyor belt, including insufficient tension, load initiation, and insufficient friction coefficient on the roller surface.

The reasons for insufficient tension include: insufficient tension stroke, insufficient counterweight weight, and too long conveyor belt;

The reasons for the insufficient friction coefficient on the surface of the roller are:

The surface coating of the roller is worn out too much, the belt is too wet or has lubricating oil stuck, and there is material stuck on the surface of the belt (which is easily swollen by water)

During the installation process, the head and tail rollers, as well as the middle support roller, should be placed on the same centerline as much as possible and parallel to each other to ensure that the conveyor belt does not deviate or deviates less. In addition, the strap joint should be correct, and the circumference on both sides should be the same. If there is deviation during use, the following checks should be conducted to determine the cause and make adjustments. The parts that need to be checked frequently for conveyor belt deviation and the corresponding treatment methods are:

(1) Check the non coincidence between the transverse centerline of the roller and the longitudinal centerline of the belt conveyor. If the non coincidence value exceeds 3mm, it should be adjusted using the elongated mounting holes on both sides of the roller group. The specific method is to determine which side the conveyor belt is biased towards, which side of the roller group moves forward in the direction of the conveyor belt, or which side moves backward.

(2) Check the deviation values of the two planes for installing the bearing seats on the head and tail frames. If the deviation between two planes is greater than 1mm, they should be adjusted to be in the same plane. The adjustment method for the head drum is: if the conveyor belt deviates to the right side of the drum, the bearing seat on the right side of the drum should move forward or the bearing seat on the left side should move backward; If the conveyor belt deviates to the left of the drum, the bearing seat on the left side of the drum should move forward or the bearing seat on the right side should move backward. The adjustment method of the tail drum is exactly opposite to that of the head drum.

(3) Check the position of the material on the conveyor belt. If the material is not centered on the cross-section of the conveyor belt, it will cause the conveyor belt to deviate. If the material deviates to the right, the belt will deviate to the left, and vice versa. When using, materials should be centered as much as possible. To reduce or avoid the deviation of such conveyor belts, material blocking plates can be added to change the direction and position of the materials.