Rolling is the standard. This chapter described the characteristics of the type commonly used in the rolling bearing, according to the working conditions of the selection of suitable bearing type and size, and combined design.

1 Overview

Rolling is the extensive use of mechanical support. Its function is to ensure there is sufficient bearing life conditions for supporting the shaft and shaft parts, and with the base for relative rotation, swing and other sports, so that the friction between the rotation to minimize, to obtain a higher gear effectiveness. Commonly used bearing has developed national standards, it is the use of rolling friction principles of design, standard mass-produced by a professional chemical plant. In mechanical design only appropriate choice of rolling bearing types and models combined structure designed according to the working conditions.

Rolling work characteristics 2

Compared with sliding bearings, roller bearings have the following advantages: (1) the application design is simple, the product has been standardized, professional manufacturers for mass production by, with excellent interchangeability and versatility. (2) Start the low friction torque, low power consumption, bearing efficiency (0.98-0.99) higher than the mixed lubrication bearings. (3) wide load, speed and operating temperature range of adaptation, a few changes in working conditions have little effect on bearing performance. (4) Most types of bearings can withstand radial and axial load, axial size is small. (5) Easy lubrication, maintenance and servicing.

Rolling also has the following disadvantages: (1) Most of the rolling bearing radial size larger. (2) When operating in high-speed, heavy load conditions, short life. (3) Vibration and noisy.

3 constituent elements and common materials

1, the bearing structure: Rolling is normally provided by the inner, outer ring, rolling elements and a cage. The inner ring is mounted on the journal (called shaft washer in the thrust bearing), with a tight; the outer ring mounted on the frame or parts of the bearing hole, usually with relatively loose. On the inner and outer ring raceway, when the relative rotation of the inner and outer ring, rolling body rolling along the raceway. Rolling body is to achieve rolling friction rolling elements, in addition to "rotation", but also around the axis of revolution. The shape of spherical, cylindrical, tapered cylindrical, needle, drum-shaped and so on. Cage's role is to separate the rolling elements evenly. In order to meet certain requirements, some bearings can be no inner or outer ring without, or with dust, seals and other structures. 2, commonly used materials: Material inner and outer rings of the rolling element and requires a high hardness and contact fatigue strength, good wear resistance and toughness. Generally with chromium alloy steel, commonly used materials GCr15, GCr15SiMn, GCr6, GCr9 etc., after heat treatment hardness up to HRC61-65. Cage general use of low-carbon steel stamping, use of high-speed bearings METALS (such as brass) or plastic cage.