BCMY R ROLLING BEARINGS HANDBOOK NTN HANDBOOK SERIES-1E corporation CAT. No. 9012-@／E *01-15 英語_*01-15 英語 16/05/19 11:08 ページ 1 NTN Rolling Bearings Handbook *01-15 英語_*01-15 英語 16/05/19 11:08 ページ 2 NTN Rolling Bearings Handbook Introduction When moving an object, friction force often comes into play, and must be surpassed to move the object. Various types of bearings are used to lessen this friction force for moving mechanisms such as machines. The bearing gets its name from the fact that it bears a turning axle or shaft, but those parts used for sliding surfaces are also called bearings. Bearings include rolling bearings, which use balls, or rollers called "rolling elements." The history of rolling bearings goes back a long time, but there has been striking technological progress in recent years. Such technological innovations have become an extremely important factor for various types of machines and equipment. This Rolling Bearing Handbook provides a description of the fundamentals and proper use of rolling bearings in easy-to-understand terms. We hope you find this information helpful. 2 *01-15 英語_*01-15 英語 16/05/19 11:08 ページ 3 NTN Rolling Bearings Handbook Contents 1 1 Rolling Bearings …………………………04 9 Bearing Internal Clearance and Preload …45 2 1.1 Sliding Friction and Rolling Friction …04 9.1 Bearing Internal Clearance …………45 1.2 Sliding Bearings and 9.2 Internal Clearance Selection …………46 Rolling Bearings ………………………04 9.3 Preload …………………………………47 3 Classification and 10 Allowable Speed …………………………53 2 Characteristicsof Rolling Bearings ……05 4 2.1 Rolling Bearing Construction …………05 Bearing Characteristics …………………54 2.2 Classification of Rolling Bearings ……06 11 2.3 Bearing Manufacturing Process ……08 11.1 Friction…………………………………54 5 2.4 Characteristics …………………………09 11.2 Temperature Rise ……………………54 11.3 Sound …………………………………55 3 Bearing Selection…………………………16 6 Lubrication…………………………………57 3.1 Selection Procedure …………………16 12 3.2 Types and Performance Comparison 17 12.1 Grease Lubrication …………………57 7 3.3 Bearing Arrangement …………………18 12.2 Oil Lubrication ………………………62 4 Main Dimensions and Bearing Numbers …19 13 External Bearing Sealing Devices ……65 8 4.1 Main Dimensions ………………………19 4.2 Bearing Numbers………………………20 14 Bearing Materials …………………………66 9 5 Bearing Precision…………………………22 14.1 Raceway and Rolling Element Materials …………66 22 5.1 Dimension and Turning Precision …… 14.2 Cage materials ………………………66 10 5.2 Bearing Precision Measurement Methods 26 15 Shaft and Housing Design………………67 6 Load Rating and Life ……………………27 11 15.1 Fixing of Bearings ……………………67 6.1 Bearing Life ……………………………27 15.2 Bearing Fitting Dimensions …………68 6.2 Basic Rating Life and 15.3 Shaft and Housing Precision ………69 Basic Dynamic Load Rating …………27 12 6.3 Adjusted Rating Life …………………28 Handling ……………………………………70 6.4 Machine Applications and 16 Requisite Life …………………………29 16.1 Mounting ………………………………70 13 6.5 Basic Static Load Rating ……………29 16.2 Post-Installation Running Test ……72 6.6 Allowable Static Equivalent Load ……30 16.3 Bearing Removal ……………………72 16.4 Press Fit and Pullout Force …………75 14 7 Bearing Load ………………………………32 17 Bearing Damage and Corrective Measures …76 7.1 Load Used for Shafting ………………32 15 7.2 Bearing Load Distribution ……………34 36 7.3 Equivalent Load ……………………… NTN Electronic Catalog Operation Method …82 7.4 Allowable Axial Load …………………37 16 Bearing Life Calculation Examples ………84 8 Fits …………………………………………39 Reference Material 90 8.1 Bearing Fits ……………………………39 (Standard Symbols for Various Countries) … 17 8.2 Fit Selection ……………………………40 8.3 Fit Calculation …………………………42 3 *01-15 英語_*01-15 英語 16/05/19 11:08 ページ 4 NTN Rolling Bearings Handbook 1. Rolling Bearings 1 1.1 Sliding Friction and Rolling Friction The force it takes to bring the object to the As shown in Fig. 1.1, the amount of force it verge of moving can be calculated as F =μ× takes to move an object of the same weight W, but the value of the coefficient of friction μ varies largely between the cases where the of a rolling bearing is a minute value of less object is laid directly on the ground and than 1/100 that of a sliding bearing. The pulled, and where the object is laid on rollers coefficient of friction of a rolling bearing is and pulled. This is because the coefficient of generally μ = 0.001 to 0.005. friction (μ) varies largely for these two cases. 1.2 Sliding Bearings and Rolling Bearings There are various forms of each type of W F bearing, each having its own particular (Weight) (Tension) F characteristics. If you compare the two, the W general characteristics are as follows. F=μ×W Fig. 1.1 Comparison of Friction Force Characteristic Rolling bearing Sliding bearing Generally has inner and outer rings, in Rotating load is supported by the surface, between which there are ball or roller rolling and makes direct sliding contact in some elements which support a rotating load by cases, or maintains sliding by film thickness rolling. using a fluid as a medium. Construction Inner ring Outer ring Rolling element Rotation axis Cross-sectional area is large due to Dimensions Cross-sectional area is extremely small. intervention of rolling element. Friction torque is large at start-up, and may be Friction torque is extremely small during Friction small during rotation, depending on the rotation at start-up. conditions. Internal clearance Can be used by making internal clearance Used with clearance. Therefore, moves only rigidity negative to provide rigidity as a bearing. the amount of the clearance. Some types can be used without lubrication; As a rule, lubricant is required. Using grease, Lubrication generally speaking, are comparatively insensitive etc., facilitates maintenance; is sensitive to dirt. to dirt. Oil lubrication conditions require attention. Can be used from high to low temperatures. Generally speaking, there are high and low Temperature Cooling effect can be expected, depending on temperature limits. lubricant. Dimensions of rolling bearings have been internationally standardized. The bearings are widely used because they are interchangeable, easy to get, and inexpensive. 4 *01-15 英語_*01-15 英語 16/05/19 11:08 ページ 5 NTN Rolling Bearings Handbook 2. Classification and Characteristics of Rolling Bearings 2.1 Rolling Bearing Construction washers," the inner ring as "shaft washer," Rolling bearings basically consist of four and the outer ring as "housing washer." 2 parts (outer ring, inner ring, rolling elements, ¡Rolling elements cage). The shapes of parts of typical bearings Rolling elements come in two general are shown in Fig. 2.1. shapes: balls or rollers. Rollers come in four ¡Rolling bearing rings (inner and outer basic styles: cylindrical, needle, tapers and rings) or bearing washer 1) spherical. Rolling elements function to support The surface on which the rolling elements the load while rolling on the bearing ring. roll is referred to as the "raceway surface." ¡Cages The load placed on the bearings is supported Along with keeping the rolling elements in by this contact surface. Generally speaking, the correct position at a uniform pitch, cages the inner ring is used fitted on the shaft and also function to prevent the rolling elements the outer ring on the housing. from falling out. Cages include pressed cages 1 In the new JIS (Japanese Industrial pressed out of metal plating, precut machined Standards), rolling bearing rings of thrust cages, and resin formed cages. bearings are referred to as "rolling bearing Part Bearing type Finished part Outer ring Inner ring Rolling elements Cage Deep groove ball bearing Cylindrical roller bearing Tapered roller bearing Self-aligning roller bearing Needle roller bearing Fig. 2.1 Comparison of Typical Rolling Bearings 5 *01-15 英語_*01-15 英語 16/05/19 11:08 ページ 6 NTN Rolling Bearings Handbook 2.2 Classification of Rolling Bearings catalogs. For terminology used for the parts of 2 Rolling bearings are generally classified as typical bearings, see Fig. 2.3. shown in Fig. 2.2. In addition to these, there are bearings of various other shapes. For more information, see the various NTN Single row deep groove ball bearings Single row angular contact ball bearings Radial ball bearings Duplex angular contact ball bearings Double row angular contact ball bearings Four-point contact ball bearings Ball bearings Self-aligning ball bearings Rolling bearing unit ball bearings Thrust ball bearings High-speed duplex angular contact Thrust ball bearings ball bearings (for axial loads) Double direction angular contact thrust ball bearings Rolling Single row cylindrical roller bearings bearings Double row cylindrical roller bearings Needle roller bearings Radial roller bearings Single row tapered roller bearings Double row tapered roller bearings Self-aligning roller bearings Roller bearings Cylindrical roller thrust bearings Needle roller thrust bearings Thrust roller bearings Tapered roller thrust bearings Self-aligning thrust roller bearings Fig. 2.2 Classification of Roller Bearings 6 *01-15 英語_*01-15 英語 16/05/19 11:08 ページ 7 NTN Rolling Bearings Handbook Width Contact angle 2 Snap ring Outer ring front face Outer ring back face Cage Outer ring Rivet Inner ring Inner ring back face Inner ring front face Ball Effective load center diameter Bearing bore Inner ring raceway Side face Pitch circle diameter Outer ring raceway Shield Bearing single outside diameter Bearing chamfer Deep groove ball bearing Angular contact ball bearing Contact angle Bearing width Inner ring with rib Outer ring Standout with 2 ribs Tapered roller Cone front face rib L-shaped loose rib Cone back face rib Effective load center Cup small inside circle diameter Roller inscribed diameter (SID) Inner ring back face Cylindrical roller Inner ring front face Outer ring front face Outer ring back face Cylindrical roller bearing Tapered roller bearing Lock washer Bearing bore diameter Locknut Shaft washer Tapered bore Sleeve of inner rib Ball height Bearing Inner ring Bearing single Spherical roller outside diameter Housing washer Outer ring Self-aligning roller bearing Thrust ball bearing Fig.