How do I choose cross roller bearings?
What are cross roller bearings?
Cross shaped roller bearings, also known as cross shaped roller bearings, generally use cylindrical or tapered rollers arranged in a single raceway in a cross shaped manner. The rollers are separated by retainers or isolation blocks. Cross shaped roller bearings have high rotational accuracy, large load-bearing capacity, small external dimensions, high rotational speed and rigidity, and have a wide range of applications and advantages that other types of bearings cannot compare with.
How to choose a cross roller bearing that is suitable for your own operating conditions correctly?
1. Selection of bearing type
There are various types of cross roller bearings, which are divided into cylindrical roller bearings and tapered roller bearings according to the structure of the rolling element. Different rolling element bearings have different characteristics and are suitable for various mechanical applications. For bearing thrust loads, thrust bearings and angular contact bearings are selected. For high-speed applications, ball bearings are usually used. For bearing heavy radial loads, roller bearings are selected.
2. Bearing size
In the selection of bearings, the size of the shaft is generally determined first, and then rolling bearings are selected based on the size of the shaft. Before selecting the cross roller bearing, it is necessary to determine the reserved space to determine the size of the bearing that can be used, minimize the mechanical installation space, and make the selection of the bearing installation position more flexible.
3. The magnitude, direction, and nature of the load on the bearing
The most important factor in bearing selection is the load of the bearing. Cross roller bearings can withstand axial and radial loads. When bearing pure radial loads, deep groove ball bearings, cylindrical roller bearings, or needle roller bearings can be selected. When bearing small pure axial loads, thrust ball bearings can be selected; When bearing large pure axial loads, thrust roller bearings can be selected. When bearings are subjected to combined radial and axial loads, cross roller bearings, YRT turntable bearings, angular contact ball bearings, or tapered roller bearings are generally selected.
4. Rigidity of bearings
The rigidity of a bearing refers to the amount of force required to produce a unit deformation of the bearing. The elastic deformation of rolling bearings is very small and can be ignored in most machinery. However, in some machinery, such as machine tool spindles, bearing rigidity is an important factor. Generally, cross cylindrical and cross tapered roller bearings should be selected because their rolling elements and raceways are in line contact and have strong rigidity when subjected to loads.
5. Speed of bearings
Each bearing model has its own limit speed, which is determined by physical characteristics such as size, type, and structure. The limit speed refers to the maximum operating speed of the bearing (usually in r/min). Exceeding this limit can cause the bearing temperature to rise, the lubricant to dry up, and even the bearing to jam. The maximum speed of grease lubricated bearings is lower than that of oil lubricated bearings, and the oil supply method of bearings has an impact on the achievable maximum speed.
6. Bearing dimensions
Before selecting the model of cross roller bearing, the size should be determined first, and then the appropriate cross roller bearing should be selected based on the size of the shaft. Before selecting the type, it is necessary to determine the reserved space, determine the size of the bearings that can be used, and minimize the installation space as much as possible to make the installation selection of bearings more free.
7. Bearing structure
Different cross roller bearings have different structures, such as outer ring split type, inner ring split type, overall structure, etc. Before selecting cross roller bearings, it is necessary to first determine which structure of bearing to choose, and see whether the part of the bearing that needs to drive rotation is the installed inner ring or outer ring of the bearing. If it is an outer circle rotation, then choose the inner circle segmentation type; Rotate the inner circle and select the inner circle segmentation type.
How to maintain cross roller bearings?
As an imported bearing, the correct lubrication of cross roller bearings is an important part of bearing maintenance during normal operation.
1. Oil bath smoothing of cross roller bearings is a commonly used smoothing method in thin-walled cross roller bearings, suitable for smoothing of medium and low speed bearings. The NSK bearing is partially immersed in the groove. Smooth oil is transported by rotating bearing components and then flows back into the oil groove. The oil level should be slightly lower than the center of the low rolling element.
2.The oil droplets of the two cross roller bearings are smooth and suitable for the parts of the thrust cylindrical roller bearings that require quantitative oil supply. The appropriate amount of oil should be dropped for 3-8 seconds. Excessive oil can cause an increase in bearing temperature.
3. The circulating oil of the cross roller bearing is smooth, and the filtered oil is stored in the bearing parts by the oil pump. The lubricating oil after the bearing is filtered and cooled. Due to the fact that circulating oil can take away a certain amount of heat and cool the bearings, this method is suitable for high-speed bearing parts.
4. The spray of the cross roller bearing is smooth. The dry shrink air is mixed with the smooth oil through the spray to form an oil mist. In cross tapered roller bearings, air flow can cool the bearings and prevent impurities from entering. This method is suitable for smooth machining of high-speed and low-temperature bearing parts.
5. The cross roller bearing radiates smoothly. The oil pump injects low-pressure oil into the bearings through a nozzle. The oil injected into the bearing flows into the oil groove through the bearing. When the bearing rotates at high speed, the rolling element and support frame also allow air to flow at a higher speed. It is difficult to deliver smooth oil to the bearing using a separate smoothing method for the turntable bearing. At this point, smooth oil must be sprayed into the bearing using low-pressure radiation, and the nozzle position should be between the inner ring and the center of the support frame.
Contact
Company:Luoyang EFANT Precision Bearing Manufacturing Co. Ltd
Address:No. 9 Jingjin North Rd, Luoxin Development Zone,
Xin'an County, Luoyang City, Henan Province 471003, China
Tel:86-379-80887690
export@efindbearing.com
https://www.efindbearing.com/contact-us
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