ASME SRB-1-2018 pdf – Design, Installation, Maintenance, and Application of Ball Slewing Ring Bearings.
intermittent oscillating slewing action: nonconti nuous, bidirectional rotation of one race with respect to the other with rotational stops for extended periods (usually measured in minutes).
internal clearance: the distance through which one of the races is displaced relative to the other, from one extreme position to the opposite extreme position, while being subjected to a minimum force sufficient to move the race; can be defined as either radial or axial.
loading plug: a plug, typically radial, installed in one bearing race that when removed allows installation of the balls and spacers during assembly.
lubrication hole: the hole(s) in a bearing race or loading plug for conveying lubricant to the rolling elements and raceways.
mounting face: a surface on the inner or outer race perpendicular to the bearing axis that transfers the load to or from the rotating or stationary structure.
oscillating slewing action: continuous, bidirectional rotation of one race with respect to the other with rotational pauses only long enough to engage and disengage the load or to reverse direction (usually measured in seconds).
outer race: a bearing race incorporating the rolling element raceway(s) on its inner diameter.
qualified person: a person who, by possession of a recognized degree in an applicable field or certificate of professional standing, or who, by extensive knowledge, training, and experience, has successfully demonstrated the ability to solve problems relating to the subject matter and work.
raceway: the load-supporting surface(s) on an inner or outer race, suitably prepared as a rolling path for the rolling elements.
radial load: load acting in a direction perpendicular to the bearing axis.
running torque: torque required to restrain motion of one bearing race while the other bearing race is rotating at a specified speed with a specified applied load.
runout (of assembled bearing): displacement of the surface ofa bearing relative to a fixed point when one bearing race is rotated with respect to the other bearing race; is specified as radial or axial runout.
seal: a circular closure comprising one or several parts, affixed to one bearing race and extending towards the other race with which it makes contact or forms a narrow labyrinth-shaped gap, for the purpose of preventing leakage of lubricant or ingress of foreign substances.
slewing ring bearing (SRB): a rolling-element bearing used for transferring/supporting axial, radial, and bending moment loads, singularly or in combination, consisting of races mounted with varying means, relatively low speed, larger diameters, and usually having a gear integral with one of the rings.
spacer: a bearing part used to separate two rolling elements.
starting torque: torque required to start rotation of one bearing race with the other bearing race held stationary under a specified load condition.
static load: load (constant or varying) acting on a bearing when its races are not rotating in relation to each other.
turntable bearing: a subset of slewing ring bearings used to rotate substantial axial and radial loads with little or no bending moment loading.
2.2 Gear Definitions
addendum: the height by which a tooth projects beyond (outside for external, inside for internal) the standard pitch circle or pitch line; also, the radial distance between the pitch circle and the addendum circle (see Figure 2.2-1 for an internal gear).
backlash: the amount by which the width of a tooth space exceeds the thickness of the engaging tooth on the operating pitch circles.
center distance (operating): the shortest distance between nonintersecting axes; measured along the mutual perpendicular to the axes, called the line of centers (see Figure
2.2-1).
circular tooth thickness: length of arc between the two sides of a gear tooth, on the specified datum (usually standard pitch diameter) circle.
clearance: the distance between the root circle of a gear and the addendum circle of its mate (see Figure 2.2-1).
dedendum: the depth of a tooth below the standard (reference) pitch circle of pitch line; also, the radial distance between the pitch circle and the root circle (see Figure 2.2-1 for an internal gear).