Needle Roller Bearing

Needle roller bearing has the advantages of small radial section size, good rigidity and high radial load bearing capacity. It is especially suitable for the occasions when the space of radial installation is limited. It can also be widely used in case of swing of shaft and bearing housing. However, needle roller bearing can only bear pure radial load and cannot limit the axial displacement of the shaft and bearing seat, and the Angle error between the axis of the inner ring and the axis of the outer ring is not allowed when the bearing is installed.

Structure and properties

Needle roller bearings are cylindrical roller bearings with a diameter smaller than the length. The roller end is slightly contracted to improve the line contact between the roller and the raceway，of which the structure can prevent peak stress at both ends of the needle roller, thus prolonging the bearing life. Although needle roller bearings have a small cross section, they have a high bearing capacity. Therefore, Needle roller bearings are ideal for bearing configurations with limited radial space.

Needle Roller Bearing

Needle roller bearings have single row and double row different structure types, depending on the use situation, no matter single row or double row needle roller bearings, can be made with inner ring NA type or no inner ring RNA type different structure types, this kind of bearing structure is characterized by the outer ring on both sides with a guard, or elastic lock ring, while the inner ring without a guard. Needle roller bearings of large size series have annular lubrication oil groove and lubricating oil hole on the outer ring. The outer ring, needle roller and cage of standard needle roller bearings are not separated. In addition to NA type and RNA type, there is NAV type and RNAV type full needle roller bearings without cage.NAOL or NAL long cylindrical roller bearings are also available, which are similar to needle roller bearings but larger in section size and suitable for heavy duty work.

Application

Combined needle roller bearings are widely used in machine tools, metallurgy machinery, textile machinery and printing machinery and other mechanical equipment, and can make the mechanical system design is very compact and dexterous.