1, basic requirements
Both the shaft and slide the INA bearings uniform close contacts, but also have a certain amount of clearance.
2, contact angle
Refers to the journal and the bearing contact surface on the center point.
Contact angle is not too big nor too small. Contact angle is too small will increase bearing pressure, severe cases can have a large bearing deformation, accelerated wear and shorten service life contact angle is too large, will influence oil-film formation, do not have access to a good liquid lubrication.
Experimental studies have shown that, sliding bearing contact angle limit is 120 °. When sliding when INA bearing wear of the contact angle and liquid damage. Therefore do not affect the sliding bearing under conditions of stress, more small contact angle, the better.
From the friction from theoretical analysis, when you contact angle of 60 °, minimum friction torque, therefore suggested that speed above 500r/min sliding bearing, contact angle of 60 °, speed lower than 500r/min sliding bearing, antennae can be 90 °, or 60 °.
3, points of contact
Journal and the bearing surface of the actual exposure, available on a unit area of physical access points to represent. Point of contact, the more, the more uniform and more, scraping the Institute of journal bearing, the better, on the contrary, it means that the sliding bearing bad scraping grinding.
Generally speaking points of contact, the more detailed the more, scraping research and move on to the more advanced. Slide the INA bearings in production should be based on performance and working conditions to identify points of contact, the information listed in the following table for reference:
Sliding bearing speed
(R/min) contact points
(Contact points on each area of 25x25 mm)
100 the following 3~5
100~500 10~15
500~1000 15~20
1000~2000 20~25
More than 2000 more than 25
ⅰ and ⅱ level precision machinery can be used on table data and table data on grade ⅲ precision machinery can be halved.
Product Model | Inside Diameter | Outside Diameter | Thickness |
7215BDB NSK | 75 | 130 | 25 |
7215ADB NSK | 75 | 130 | 25 |