What's the application and selction of swing bearing?

Slewing bearings has a unique bearing capacity and is usually used on lifting machines, excavators, rotary tables, wind turbines, telescopes and tank turrets. With the improvement of machining methods and the update of design concept, today's slewing bearings can be applied to smaller, more complex and more sophisticated applications.

In the machine tool industry, the slewing bearings of standard structure is applied with high precision grade and preload to eliminate gap and reduce vibration. The radial runout of the slewing ring and the diameter tolerance range from one thousandth to one thousandth of an inch (2. 54 tan), compact structure, small section size, and the diameter range can be as small as 50 mm(this type of slewing supported steel ball size is smaller than the traditional heavy series slewing bearings steel ball size). This prompted the designers to reconsider the traditional slewing ring configuration.



Derrick post shafts for bearing radial, axial, and torque loads are installed with two sets of ball or roller slewing bearings set at intervals along the shaft.However, for this configuration, due to space constraints and installation complexity, it is difficult to adapt to new applications, which is the advantage of slewing bearings.The replacement of two sets of slewing bearings with one set not only reduces the height of the device, but also simplifies the structure of the components.

The correct choice of slewing bearings depends on the requirements of loading, stiffness, speed, size and rotational flexibility.The design objective and the applicability of slewing bearing are discussed jointly by the user and the slewing bearing manufacturer, which is helpful for the system to achieve the optimal performance under the premise of the lowest cost and guarantee of trouble-free operation.

Even if no previous experience can be used for reference, the better design is still a set of four-point contact ball bearing.The cross contact Angle forms a large effective nodal circle diameter to offset the overturning moment.In addition, the single slewing bearings with large size can make the contact line between the ball and the channel through the center of the inner hole.This simplifies the overall design, improves the appearance and protects the parts.Although four-point contact ball bearings have been used for many years in construction machinery such as cranes, backhoe and excavator, these bearings have also been widely used in special machinery.These devices include robots, lifting turns, locomotives and radar bases.

Generally,the load capacity is the deciding factor to select slewing bearing size and diameter,and other parameters decide which type slewing ring is the best choice.