Abstract: The SHI252 hydraulic disc brake pad elevator, as the main tool for
transporting materials in coal mines, undertakes the main task of coal mine
transportation. Its normal operation is the prerequisite for ensuring safe
production, and whether it can operate normally is the the final say of brake
shoe clearance. Too large or too small brake shoe clearance will affect the
brake system of the elevator, so the brake shoe clearance can determine whether
the elevator can operate normally. However, in normal production, it is quite normal for the brake shoes of
the hoist to wear out quickly. If you do not notice at this time, or if the wear
rate of the brake shoes accelerates and you have not had time to replace them,
it will inevitably affect the normal operation of the hoist, and the incidence
of safety accidents will greatly increase. Therefore, in view of the rapid wear and tear of the hoist brake shoes,
installing brake shoe protection is an effective means to avoid safety
accidents. The reason why we are so confident in coming to this conclusion is
because of the unique features of brake shoe protection: 1、 Gap detection of gates Detection principle: By using a displacement sensor, a distance of 0-10mm
is converted into a voltage signal of 010V, which is transmitted to the analog
input module of the PLC. Due to the impossibility of tightly adhering the end
face of the sensor to the brake disc, a certain distance is set to the 0
position, such as setting 4mm as the 0 position. When in the closed state,
adjust the displacement sensor so that the sensor end face is approximately 4mm
away from the brake disc, and set it as 0. When the gate is opened, if the
detected distance is 5. Imm, then the gate gap is 5.1mm-4.0mm=1.1mm. However,
after long-term operation, there will be a certain amount of wear on the brake
shoes. Assuming the wear value of the brake shoes is 1.2mm, at this time, when
in the closed state, the distance detected by the sensor is Imm 1.2mm=2.8mm,
while when the brake is opened, the distance detected by the sensor is
5.1mm+1.2mm=6.3mm. At this time, the gap between the brake shoes is
6.3mm-4.0mm=2.3mm. (It can be seen that both spring fatigue and brake shoe wear
will increase the brake clearance). The above calculations are all completed in
the PLC controller. In actual use, simply adjust the sensor to * * * 0 position
in the closed state 2、 Brake shoe wear detection The detection principle of brake shoe wear: When the output oil pressure of
the hydraulic station is detected as 0 or residual pressure, if the value of the
distance sensor is less than 0 (negative), it is considered that the value is
caused by brake shoe wear. The reverse of the change value is the wear amount of
the brake shoe. (This value may also be caused by the bias of the brake disc,
and the impact of the bias needs to be deducted in the specific fault
diagnosis). 3、 Brake disc deflection detection Calculation of brake disc deflection: Fixed to the brake seat by a distance
sensor, the winch detects the maximum and minimum values of the distance during
operation, and the difference between the maximum and minimum values is the
deflection. How about it? After reading the above content, you will understand why the
editor confidently said that "installing brake shoe protection is an effective
means to avoid safety accidents." It is recommended that coal mine operators
always tighten the safety string, nip accidents in the bud, and start with
installing brake shoe protection
The SHI252 hydraulic disc brake pad elevator, as the main tool for
transporting materials in coal mines, undertakes the main task of coal mine
transportation. Its normal operation is the prerequisite for ensuring safe
production, and whether it can operate normally is the the final say of brake
shoe clearance. Too large or too small brake shoe clearance will affect the
brake system of the elevator, so the brake shoe clearance can determine whether
the elevator can operate normally.
However, in normal production, it is quite normal for the brake shoes of
the hoist to wear out quickly. If you do not notice at this time, or if the wear
rate of the brake shoes accelerates and you have not had time to replace them,
it will inevitably affect the normal operation of the hoist, and the incidence
of safety accidents will greatly increase.

Therefore, in view of the rapid wear and tear of the hoist brake shoes,
installing brake shoe protection is an effective means to avoid safety
accidents. The reason why we are so confident in coming to this conclusion is
because of the unique features of brake shoe protection:
1、 Gap detection of gates
Detection principle: By using a displacement sensor, a distance of 0-10mm
is converted into a voltage signal of 010V, which is transmitted to the analog
input module of the PLC. Due to the impossibility of tightly adhering the end
face of the sensor to the brake disc, a certain distance is set to the 0
position, such as setting 4mm as the 0 position. When in the closed state,
adjust the displacement sensor so that the sensor end face is approximately 4mm
away from the brake disc, and set it as 0. When the gate is opened, if the
detected distance is 5. Imm, then the gate gap is 5.1mm-4.0mm=1.1mm. However,
after long-term operation, there will be a certain amount of wear on the brake
shoes. Assuming the wear value of the brake shoes is 1.2mm, at this time, when
in the closed state, the distance detected by the sensor is Imm 1.2mm=2.8mm,
while when the brake is opened, the distance detected by the sensor is
5.1mm+1.2mm=6.3mm. At this time, the gap between the brake shoes is
6.3mm-4.0mm=2.3mm. (It can be seen that both spring fatigue and brake shoe wear
will increase the brake clearance). The above calculations are all completed in
the PLC controller. In actual use, simply adjust the sensor to * * * 0 position
in the closed state
2、 Brake shoe wear detection
The detection principle of brake shoe wear: When the output oil pressure of
the hydraulic station is detected as 0 or residual pressure, if the value of the
distance sensor is less than 0 (negative), it is considered that the value is
caused by brake shoe wear. The reverse of the change value is the wear amount of
the brake shoe. (This value may also be caused by the bias of the brake disc,
and the impact of the bias needs to be deducted in the specific fault
diagnosis).
3、 Brake disc deflection detection
Calculation of brake disc deflection: Fixed to the brake seat by a distance
sensor, the winch detects the maximum and minimum values of the distance during
operation, and the difference between the maximum and minimum values is the
deflection.
How about it? After reading the above content, you will understand why the
editor confidently said that "installing brake shoe protection is an effective
means to avoid safety accidents." It is recommended that coal mine operators
always tighten the safety string, nip accidents in the bud, and start with
installing brake shoe protection