EPEN Technology Knowledge: Wear analysis of sliding bearing of mine hoist

  • The maintenance and adjustment measures of the sliding bearing of the hoist are put forward

The maintenance and adjustment measures of the sliding bearing of the hoist are put forward

 

With the rapid development of science and technology, advanced technology has been widely used in coal mine equipment. In coal mine hoists, the use of sliding bearings has greatly improved the performance of the hoists and the accuracy. Therefore, the use of sliding bearings in coal mine hoists is more extensive. During the use of the sliding bearing of the hoist, due to some factors of its own configuration, the maintenance cost of the sliding bearing of the hoist is high, especially the wear of the sliding bearing. Through the analysis of the reasons for the wear of the sliding bearing of the coal mine hoist, this paper puts forward the measures to strengthen the maintenance and adjustment of the sliding bearing of the hoist, aiming to provide a theoretical reference for the overall benefit of the hoist.

 

 

1 Reasons for wear of sliding bearing of coal mine hoist

(1) Bearing defect

Some defects of the bearing itself are one of the reasons leading to the wear of the sliding bearing. The bearing defects include three aspects: first, the poor quality of the tin hanging causes some problems in the combination of the bearing bush backing layer and the lining layer; Second, in the process of pouring the bearing bush, due to the temperature (insufficient heat), the gas is stored in the hanging bush; Third, there are large particles in the tin antimony alloy, which makes the particles in the Babbitt alloy uneven. These are the defects of the bearing itself.

 

(2) Nonstandard assembly

The assembly of the sliding bearing was not carried out according to the standard requirements, and the wear problem also occurred in the later stage, which was manifested in the following three aspects: first, the centerline of the bearing and the centerline of the base did not coincide; Second, the bearing and the base do not match, which will cause dangerous problems such as sliding; Third, the gap between the bearings is not uniform, and the bearing exceeds the standard. The above are the manifestations of the bearing not meeting the assembly standard.

 

(3) Improper use of bearing

One of the most important reasons for the wear of sliding bearings is the improper use of bearings. Improper use is manifested in the following three aspects: first, the entry of foreign particles into the bearings; Second, improper use of lubricating oil additives will corrode bearings; Third, bearing wear caused by insufficient lubricating viscosity.

 

2 Strengthen maintenance of sliding bearing of hoist

(1)Maintenance technology of sliding bearing of hoist

During the use of the sliding bearing hoist, several maintenance processes are proposed according to the use conditions, namely, the maintenance of various parts of the sliding bearing: first, when the power supply is cut off, measure the clearance between the rotor and stator of the motor to ensure that it is within the reasonable range; Second, detect and remove the coupling shell, measure the clearance of the end face, and ensure that it is within the standard range; Third, check and remove all parts of the motor, measure the bearing clearance and shaft level to ensure that they are within the standard range; Fourth, detect the wear of the shaft circumferential surface at the bearing, and carry out corresponding treatment according to the specific situation to make it meet the standard; Fifthly, detect the wear of bearing bush and make corresponding adjustment, clean the bearing base to ensure its cleanliness; Sixth, check the installation between the lower bearing bush and the motor rotor to see if the installation is completed according to the standard. After installation, measure the levelness of the shaft to make it reach the standard range.

 

After maintenance, the above parts and components shall be installed in the hoist system according to the standard, and then corresponding commissioning shall be conducted to ensure the normal operation of the sliding bearing of the hoist.

 

(2) Maintenance of sliding bearing in operation

a. Temperature detection

For the maintenance of the sliding bearing in operation, the first thing to consider is whether the temperature meets the standard. If the temperature is too high or too low, the gap between the bearings will be affected, resulting in bearing failure. Therefore, it is very necessary to detect the temperature of the bearing in operation. The specific purpose is to measure the temperature through the temperature measuring hole of the bearing and use the thermal resistance to detect. Once the temperature is too high or too low, It is reflected to the summing up port through the interface of PC to remind the temperature, so as to take effective measures to avoid bearing failure caused by temperature.

 

b. Detection of running vibration

If the amplitude of the bearing is too large during operation, it will also cause bearing failure, thus affecting the performance of the hoist. Therefore, the corresponding technology should be used to detect the amplitude during operation. This time, the displacement sensor detection technology is used. Through the detection results, the amplitude fault can be repaired and improved to avoid the bearing fault caused by excessive amplitude.

 

c. Regular ferrographic analysis

Ferrography analysis is to detect the lubrication degree and bearing friction. If the lubricating oil does not meet the standard, the friction debris generated by bearing friction will have a certain impact on the bearing. Therefore, bearing failure can be effectively avoided by ferrography analysis and detection.

 

3 Clearance determination of sliding bearing and other adjustments

There are two main clearance types of sliding bearings, namely radial clearance and axial clearance. The two clearances are important conditions to ensure the normal and continuous operation of the hoist. The former is to ensure the accurate operation between the journal and the bearing, and the latter is to ensure that the length of the journal can expand and contract freely when the temperature rises. The following is the description of the determination of the bearing clearance and other adjustments: first, the clearance is determined, and the radial clearance of the sliding bearing is determined, Generally speaking, it is based on the nature of design assembly. As for the determination of the axial clearance of the sliding bearing, it must be combined with its specific structural form to ensure that it is greater than the longest expansion and contraction during the operation of the journal. Generally, the structural form must be determined according to the different structures; Second, to measure and adjust the clearance of the sliding bearing, the journal must be arranged at? The clearance of the sliding bearing can be determined only after the end position. The axial clearance can be obtained by using the dial gauge, feeler gauge and other relevant measurement operations, and then superimposing the data of these two extreme positions for calculation; Third, adjust the clearance. If the top clearance of the sliding bearing is greater than the limit value, it is necessary to reduce the adjustment force of the pad mouth to ensure that the force is appropriate.

 

4 Conclusion

To sum up, the rational and scientific use of the coal mine hoist is very helpful to improve the productivity of the coal mine. As an important component of the hoist, the sliding bearing has a direct impact on the production efficiency of the coal mine. Therefore, the analysis and Research on the wear of the sliding bearing of the hoist can ensure the normal operation of the hoist, reduce the number of equipment maintenance and reduce the cost, so as to improve the economic benefits of the coal mine enterprises and promote the development of the coal mine industry.

 

More about Epen E90 Bushing: 

E90 bronze wrapped bushings are made of entirely bronze CuSn8. Because of material properties, the working surface rolled with diamond Indentations (standard Indentations) or stamped oil grooves according to detailed application. And it also has good performance of anti-corrosion caused by chemical and environments. During the operation, the grease & oil will be released from the indentations, which allow for long-term lubrication. Compare with machined bronze bearings, E90 can offer some advantages including thin wall, lower weight, cheaper cost, high load etc. It is suitable for high load, lower speed application like construction, transport, and agriculture machinery.

 

 

 

Jiashan Epen Bearing Co., Ltd. is a professional manufacturer of sliding bearings, metal plastic composite bearings business, specializing in adhering to do fine, the better for our customers continue to create value concept, is committed Sliding Bearings, new composite materials research, development, promotion and applications. Company's existing main products for metal-plastic composite series Sliding Bearings, bimetal bearings, sliding bearings single metal series, are widely used in automotive, metallurgy, engineering machinery, construction machinery, plastics machinery, machine tool industry, water conservancy and hydropower 30 a number of areas.