ASME SRB-1:2018 pdf free download – Design, Installation, Maintenance, and Application of Ball Slewing Ring Bearings
This Standard applies to the design, application, instal- lation, inspection requirements, and maintenance of slewing ring bearings (SRBs) using balls that do not require dynamic capacity-life ratings. These also may be called slewing rings. This is inclusive of four-point contact single-row and double-row ball bearings. Such bearings are used in, but not limited to, equipment such as hydraulic shovels, excavators, aerial platforms (manlifts),cranes, wind-powergenerators,buildingmain- tenance units (BMUs), and other equipment where one part of the structure must rotate with respect to another in an oscillating or indexing manner.
The purpose of this Standard is to define standard methods to evaluate variables and establish practices for satisfactory performance in ball SRBs in oscillating or indexing applications. This will allow effective commu- nication and exchange of data among the user, installer, and SRB manufacturer such that all parties understand each other’s requirements and have a common point of reference. Certain parameters are standardized to reduce the potential for confusion between the SRB manufacturer and the user. Acceptance criteria and guidelines are provided for SRB design, material, inspection require- ments, and application.
angular contactbearing: a rolling-element bearing with a nominal contact angle between 0 deg and 90 deg. axial load: a force acting in a direction parallel with the bearing axis. ball: a spherical rolling element. ball grade: a specific combination of dimensional, form, surface roughness, and sorting tolerances for balls as defined in ABMA 10A or ISO 3290-1. ball path: the area where the rolling elements (balls) ride between the races. ball-path diameter: the diameter that corresponds to the centerline of the balls as shown in Figure 2.1-1. bearing preload: the absence ofinternal clearances; canbe described as either radial or axial. bending moment: effect of an applied force at a distance from the axis of rotation. conformance: ratio of ball-path radius to ball diameter. contactangle: the angle between a plane perpendicular to the bearing axis and a line passing through the contact point and the center of the rolling elements (see Figure 2.1-1). contactpoint: the point ofcontact between a ball and one raceway. dynamic load: a load (constant or varying) acting on a bearing when its races rotate in relation to each other. face: a surface of a race perpendicular to the axis of the race.
fixed quadrant slewing action: oscillating or intermittent slewing action thatoccurs 50% or more ofthe time in one 90-deg quadrant. four-point contact ball bearing: a single-row angular contact ball bearing in which, when under purely radial load, each loaded ball makes contact with each of the two raceways at two points; under pure axial load, each loaded ball makes contact with each of the two raceways at one point. inner race: a bearing race incorporating the rolling element raceway(s) on its outer diameter. integral seal: a bearing sealing device that is an integral part of an assembled bearing.