Wear And Maintenance of Elevator Sliding Guide Shoes

Wear And Maintenance of Elevator Sliding Guide Shoes

The function of elevator sliding guide shoes

The guide shoe is a device that prevents the car and counterweight from deflecting when running up and down, and ensures the smooth operation of the elevator. The guide shoes need to be installed on the car and the counterweight device. The car guide shoes are installed on the upper beam of the car and under the bottom safety gear seat respectively; the counterweight guide shoes are installed on the upper and lower parts of the counterweight frame. In this way, during the operation of the elevator, the concave groove of the guide shoe will match the convex shape of the guide rail, allowing the car and counterweight to move up and down along the working surface of the guide rail.

The fixed sliding guide shoe is mainly composed of a boot lining and a boot seat. The position of the boot head is fixed, and the boot lining matches the top surface and both sides of the guide rail, with a large gap in the middle. Installing the fixed sliding guide shoe between the car and the counterweight device cannot guarantee the stable operation of the elevator, but it can make the elevator have a greater bearing capacity. Therefore, the fixed sliding guide shoe is usually used in freight elevators.

Wear of elevator sliding guide shoes

1.Boot lining materials for elevator guide boots

Nylon boot lining and hard plastic boot lining have different friction levels under the same working conditions.From this, it can be determined that boot linings made of different boot lining materials have different friction capabilities. As there are currently nylon, hard plastic, glass fiber, polymer materials and other materials on the market that can be used for making boot linings, the most suitable boot lining material should be selected based on the actual situation.

2.Lubrication status of elevator guide shoes

Under the action of lubricant, the dry friction between the guide rail and the shoe lining will be converted into wet friction, the friction factor will be reduced, and the corresponding friction between the two will be reduced, which will help avoid guide shoe wear. It can be seen from this that if the lubrication state between the guide shoe and the shoe lining is good, the possibility of guide shoe wear will be reduced; on the contrary, the possibility of guide shoe wear will increase.

3.Contact pressure of elevator guide shoes

Ideally, there is no contact pressure between the guide shoe and the rail surface. However, in actual elevator operation, it is difficult to avoid the occurrence of car load offset. Once the car load is offset, a balancing reaction force will be generated, causing the guide shoes to act on the guide rail surface and generate contact pressure. Generally speaking, the friction factor decreases as the normal pressure increases. Therefore, the contact pressure will affect the friction strength between the guide shoe and the guide rail working surface, which will indirectly affect the wear degree of the guide shoe.

4.Surface roughness of elevator guide boots

Based on physics, we can know that the surface roughness of two objects in contact with each other will affect the friction force generated by the interaction between the two objects. That is, the rougher the surface, the greater the friction force; conversely, the smaller the friction force. This theory also applies to the guide shoe and guide rail working surfaces, that is, the roughness of the guide shoes and guide rail working surfaces has a great impact on the wear of the guide shoes.

Maintenance of elevator sliding guide shoes

1.Adjust the gap between the side of the car guide shoe and the guide rail

According to the requirements of the "Elevator Usage Management and Maintenance Rules", the gap between the side of the shoe lining and the guide rail of the car guide shoe should be set between 0.5 and 1mm. However, because the actual application conditions of different types of guide shoes are different, when using elastic sliding guide shoes, it should be ensured that there is no gap between the guide shoe lining and the top surface of the guide rail; when using fixed sliding guide shoes, the guide shoe lining and the top surface of the guide rail should be ensured. The gap on the top surface of the guide rail is controlled at 1~2mm.

2.Check the horizontal position of the guide shoe

In order to ensure that the elevator can be used safely, during daily maintenance of the elevator sliding guide shoes, attention should be paid to checking the upper and lower guide shoes of the car and counterweight device to determine whether the guide shoes are in a horizontal position. If the guide shoes are not in a horizontal position, , which should be adjusted. In addition, the size of the gap between the guide shoe and the guide rail should also be checked. If the gap is found to be too large, the shoe lining should be removed, a gasket should be added to it, and then the shoe lining should be installed. This can shorten the length of the gap. The gap between the guide shoe lining and the guide rail. However, if the gap is too large and the gap between the boot lining and the guide rail is still larger than the standard requirement after adjusting the boot lining, the boot lining needs to be replaced.

3.Keep guide rails clean and lubricated

The lubrication state between the guide shoe and the guide rail directly affects the wear degree of the guide shoe. In order to avoid the wear of the sliding guide shoes of the elevator as much as possible, during the maintenance process, they must be cleaned according to regulations, and lubricants should be used appropriately to improve the lubrication state between the guide shoes and the guide rails.