Four-point contact ball slewing bearings have a single outer ring and a split inner ring. The raceway profiles are such that the ball contacts the outer ring at two points and the split inner ring at one point each. Such a design allows the bearing to carry axial loads in both the directions like a double row angular contact ball bearings without taking up as much axial space. These bearings can support light radial loads.
Typical manufacturing for four-point contact ball bearings is of traditional antifriction bearing material. Of course, the application will call for any specific material, just like any other bearing. This can mean high-carbon alloy or stainless steel are necessary choices. Depending on the manufacturer, there may be other characteristics in a four-point contact bearing.
Four-point contact bearings are primarily utilized for slow to moderate-speed applications with mainly oscillatory movements, but application specific bearings can also be designed, if needed. A thirty-five degree contact angle off the radial center line is typical, but again, this can be varied to match the application.
What makes this type of bearing special, and a tremendous help in machine simplification, is that with each axial load it supports, a radial load can also be supported, simultaneously. This idea simplifies machine designs with a combination of axial, radial, and moment loads. With the four-point contact bearing taking place of double row bearings, much less space is required in the machine. Wow – so we know the four-point contact bearing can handle all three types of load, in any order thrown at it. But, besides tossing aside the need for one bearing, what other benefits do they have?
Since a four-point contact bearing can take on multiple jobs at once, a second bearing is rendered unnecessary. Without a second bearing…
No need for runout or diameter matching
No chance of wobble from two bearings that develop unequal runout
No more maintenance necessary than any other bearing (perhaps less)
As bearing technology continues to change and grow, machines are getting smaller, more dependable, and less work to maintain. These are all good things, which is why embrace these changes. Follow along with us here, as we strive to always keep you informed.
4 Point Contat Ball slewing bearings are widely used in the well rig for oil field, wind turbine, medical equipments, excavator , high-speed wire finishing mill,marine propeller,coal mining machine,cement mill,large scale precision reducer and so on.