SoCare Slewing ring bearing features

Inner and outer rings (1 and 2) 

The bearing consists of an inner and outer ring made of  medium carbon steel. Each includes at least one precision raceway arranged to transfer loads and relative motion from one structure of the equipment to the other. The  raceways are selectively hardened to the required surface  and depth necessary to transmit high stresses imposed  during operation of the equipment. 

Figure 2-5 reflects the  typical hardness patterns of four-point ball (RK, HS, HT, MT,  KH, and XT Series) and cross roller (XR Series) bearings.  Multiple row bearings (DT and TR Series) receive similar  treatment in their highly stressed raceways. 

In one location  around the raceway, there is an unhardened area referred  to as the hardness gap or “soft spot.” This area is relieved to  minimize the ability of the rolling element to apply stress on  it. 

Only one side of each ring is manufactured to be mated  with the supporting structure. One or both rings may  include an integral drive mechanism such as gear or  sprocket teeth to enable the mechanical advantage necessary to overcome rotational resistance and provide  relative motion through the bearing.

Rolling elements (3) 

Precision rolling elements enable relative rotation and  transmit load between the inner and outer rings. Hardened  chrome alloy steel balls or rollers may serve as the rolling  elements. They are sized appropriately for the anticipated  stresses and closely matched to provide uniform load distribution between the rings and minimize rotational  resistance.

Spacers (4) 

Spacers separate the rolling elements and are designed to  minimize friction, skidding, and jamming during rotation.  These conditions occur as a result of load distribution and  distortion of the mounting structures and bearing rings  during operation of the equipment. Spacers are generally  made of a plastic material compatible with typical  lubricants and operating environments.  Occasionally for ball bearings, a ball of smaller size is placed  between the larger load-carrying balls instead of a spacer.  These are referred to as “spacer balls” and can provide a  solution to a unique condition specific to a particular  application. Where the application warrants, a separator is  used in place of the spacers or spacer balls.

Mounting holes (5) 

The ideal hole pattern for attaching both rings of the slewing  ring bearing is a full circle of uniformly spaced through holes.  It is recognized, however, that the equipment designer  cannot always accommodate this type of arrangement and  may require tapped holes and even special bolt patterns in  one or both rings for assembly and maintenance reasons. 

Seals (6) 
A seal is included on each side of SoCare slewing ring  bearings for retention of lubricant and protection of the  bearing from dust and small particle contamination. The  seals are made of an elastomer material compatible with  most general purpose lubricants having mineral oil and  greases using lithium or calcium thickeners. If conditions  require different sealing, SoCare can provide details of  additional options upon request.

Loading (Filler) Plug (7) 

The rolling elements in SoCare bearings may be inserted  through a hole drilled radially through the non-geared race  and then plugged. The plug is retained mechanically with a  pin to assure proper orientation is maintained. TR Series  bearings, however, do not have a loading plug as they require one of the rings be split for assembly of all the rolling  elements.

Gear (8) 

Slewing ring bearings can be supplied with gear teeth as an  integral part of either the inner or outer ring. They are  typically a standard full depth or stub involute spur gear  having a 20° pressure angle with provision for backlash and  conforming to AGMA Q6 quality.  However, where required, modifications of the basic tooth  forms, pressure angles, and quality can be provided. For  assembly purposes, the maximum point of gear runout is identified with yellow paint. Alternative methods may be  applied upon request.

Grease Fitting (9) 

At least one grease fitting is supplied in one of the bearing  rings for periodic lubrication of the raceway and internal  components. On designs with integral gear teeth, it is  located in the non-geared ring. The number supplied  typically increases with bearing diameter. More or less may  be included upon request.

Identification (10) 

Identification consists of the bearing part number and serial  number. This information is located next to the filler plug.