Drawn Cup Needle Roller Bearings

Transcription

1 Drawn up Needle Roller Bearings NSK has introduced the most advanced bearing technology, offering unprecedented precision and reliability. Available in two types caged and full complement.

2 High-quality bearings that meet demanding performance standards. Drawn up Needle Roller Bearings 1. High load capacity 2. High limiting load 3. Wear resistant 4. Easy to mount High load capacity with the thinnest outer ring among High-load tolerance is made possible with a special The high-precision finished cage is surface-hardened The simplified setup process allows the roller to existing roller bearings. steel plate carefully selected by NSK. to improve wear resistance. flexibly adapt to various applications. 1 2

3 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings NSK drawn cup needle roller bearings (caged and full-complement types) have a unique outer ring structure including the following features: the thinnest outer ring among rolling bearings, high load capacity, high limiting load owing to the use of carefully selected special alloy steel plates, a surface-hardened and highly wear-resistant cage, high limiting speed, and ease of mounting. 1. Design and Types NSK drawn cup needle roller bearings consist of an outer The bent lip of the drawn cup, which is the outer ring, ring made of carefully selected alloy steel that is surfacehardened after precision pressing, rollers made of vacuum- functions as a labyrinth seal to prevent foreign matter from improves rigidity, holds the rollers and cage in place, and degassed bearing steel that is through-hardened and given entering and lubrication from escaping. The inside of the a grinding finish, and a cage that accurately guides the outer ring is hardened to resist wear from contact with the rollers on the pitch diameter. roller or cage. 2. Specification Number ode FJ means a metric open-type bearing with a cage Shaft dimension number Width dimension number Example (metric): FJ ode JH means an inch open-type bearing with a cage Shaft dimension number Width dimension number Example (inch): JH The bearing numbers of NSK drawn cup bearings are shown in combination with bearing codes and dimension numbers. The bearing codes are shown in Table 1. The dimension number has the following meaning: Metric Inch ategory Metric Table 1 Bearing odes ode Inch Example The first one or two numerals indicate the shaft dimension, and the next two numerals indicate the width, both expressed in mm units. The first one or two numerals indicate the shaft dimension, and the next two numerals indicate the width, both expressed in units of 1/16 of an inch. With closed ends, the number 1 is added at the end of the width dimension number. With age Assembly Standard Series FJ FJP J 3. Accuracy Although standard drawn cup needle bearings perform well for general use, higher-accuracy drawn cup needle bearings may be required, for example when: Dispersion of radial internal clearance needs to be sharply decreased Eccentric effects should be minimized The load must be shared evenly by a small number of bearings Please consult with NSK when selecting high-accuracy bearings. FJL JH High Load Series Standard Series FJH F NF Housing Bore Diameter φ 37 N Bearing Inscribed ircle Diameter (when pressing into ring gauge of ) φ Shaft Diameter φ 3 h6.13 Radial learance.15 ~.74 mm Square Mean Value.27 ~.62 Internal clearance When a drawn cup needle bearing is mounted in a housing, the radial internal clearance varies according to the bearing, shaft and housing bore tolerances. For example, the tolerances for the shaft and housing bore should be narrower when reducing the range of radial internal clearance. When the dimensional tolerance for each part is as shown in Fig. 1 (Example of F-32-1), the radial internal clearance ranges from.15 to.74 mm. Full omplement DD High Load Series FH NFH Fig. 1 Radial Internal learance 3 4

4 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings 4. Application to Maximize Performance Shaft and housing specifications For drawn cup needle bearings, the shaft is generally used as a substitute for the inner ring. Since the outer ring is made of thin steel plate, the correct shape and dimensional accuracy are determined after press fitting of the regular housing. Dimensional accuracy, shaft hardness, and housing bore directly affect bearing performance. Therefore, the following specifications should be satisfied: Accuracy, roughness, and hardness Accuracy, roughness, and hardness of the shaft and housing bore should satisfy the specifications shown in Table 2. Accuracy and roughness of fitting surfaces Since the raceway rings of needle bearings are extremely thin, the raceway surface is greatly affected by the accuracy of the shaft and housing. For general operating conditions, a turned finish, smooth bored finish, or reaming finish is acceptable. For high accuracy and low noise under heavy load, however, a grinding finish is required. A finish roughness of less than 1.6 µmr a is desirable. Accuracy and roughness of the raceway surface The shaft is often used as the raceway surface of needle bearings in order to achieve the most compact bearing design and enhance shaft rigidity, load capacity, and accuracy. In this case, accuracy and roughness of the raceway surface greatly affects the life, noise, and accuracy of bearings. Therefore, shape, accuracy, and roughness have to be treated with great care. In particular, harmful circumferential waviness and a polygonal shape are not desirable. Accuracy and roughness for raceway surfaces are shown in Table 2. Since these values may change depending on desired performance, please consult NSK. Table 2 Accuracy, Roughness and Hardness ategory Shaft Housing Bore Out-of-Roundness IT3 IT4 ~ IT5 Tolerance ylindricity IT3 IT4 ~ IT5 Tolerance Roughness, R a Hardness Housing rigidity HR58~64 Proper depth of hardening layer required Shaft inclination Shaft inclination due to deflection by an external force and mounting error of the bearing should be within the values found in Table 3. Material and heat treatment of raceway furnace The raceway rings and rollers of needle bearings are repeatedly stressed on their relatively small contact surfaces. The materials for raceway rings, rollers, and shafts and housings that function as raceways, must therefore have high hardness, resistance to permanent deformation, and long rolling fatigue life. These materials are also required to be resistant to wear and shock, and have good dimensional stability. ommon materials used for shafts and housings that function as bearing raceways include the following: High-carbon chromium bearing steel (for through hardening) SUJ2 (JIS G 485) arbon steel for machine construction (for carbonizing) S15K (JIS G 451) hrome molybdenum steel (for carbonizing) SM415~421 (JIS G 415) hrome steel (for carbonizing) Sr415, 42 (JIS G 414) Nickel chrome steel (for carbonizing) SN415~815 (JIS G 412) Nickel chrome molybdenum steel (for carbonizing) SNM22, 415, 42 (JIS G 413) JIS: Japanese Industrial Standard Other materials, such as S5 and S55, can be utilized with through hardening or induction hardening. The hardened layer, which is tempered at 16 to 18 after hardening, has to develop a martensite structure with an even distribution of very fine carbides. In the case of cemented or induction hardening of the raceway surface, the surface hardness should not only be HR58 to 64 (HR6 to 64 is preferable), but also the hardened layers with Vickers hardness of HV 653 (HR58) and HV55 (HR52.3) have to reach appropriate depths. When the values of hardness are below these values, bearing fatigue life significantly decreases. The hardened layer depth (up to HV55) after grinding finish is estimated by using the following equation: t (.8~.1) D w where, t: Effective hardened layer depth (mm) D w : Roller diameter (mm) ore hardness is generally HR3 to 45. Table 3 Shaft Inclination Bearing Width (mm) Permissible Inclination (mm/mm) over incl. With age Full omplement To maintain the accuracy of drawn cup needle bearings, it is necessary to design the housing thick enough to minimize deformation when load is applied. Split housings can only be used with drawn cup needle bearings after press fitting the bearing into a cylindrical sleeve. 5. Adjustment of Fitting Drawn cup needle bearings perform as designed only after proper fitting. It is necessary to use the fitting tolerances shown in Table 4 for the shaft and housing bore. The figures in Table 4 are for fittings when housing materials are rigid steel or cast iron. The fit should be adjusted as follows in accordance with operating conditions: (1) Oscillating motion (3) The housing is made from light alloy or steel with In order to reduce radial internal clearance, the shaft s a thickness of less than 6 mm. fitting tolerance should be js6 (j6). The fitting tolerances of the housing bore should be (2) Outer ring rotation minimized to approximately.13 to.25 mm, For metric bearings, the fitting tolerances of the shaft provided that the optimized value should be determined and housing bore should be f6 and R7, respectively. by mounting into the actual housing, as the optimized value may vary depending on housing material and shape. Please contact NSK for details. Table 4 Recommended Fits Fitting Tolerance ategory Shaft Housing Bore F, FJ h6 N7 Metric FJL h6 J7 Nominal Outside Diameter D, mm Tolerance, mm B, BH over incl. high low Inch J, JH h ( 9 / 32 ) +.13 Y, YH ( 9 / 32 ) ( 11 / 32 ) ( 11 / 32 ) J7 15 Locating Stopper A Recommended Jig Dimensions Marked Side of Bearing D A = Housing Bore Diameter -.4 mm E B = Shaft Diameter -.8 mm =.25 mm (min.) B D = Bearing Width -.8 mm E = Approximately 1/2 D Fig. 2 Example of Jig 5. Mounting Precautions When a drawn cup needle roller bearing is pressed into a housing bore, it is necessary to use an appropriate jig to prevent deformation of, and damage to, the outer ring, as shown in Fig. 2. (1) The marked-side face should be placed onto the shoulder of the jig. (2) A hand press should be used for press fitting. Avoid using a hammer or other such instruments. (3) Use of a snap ring or shoulder to determine the position of the bearing is not necessary. However, when using a housing with a shoulder, the bearing side face should not touch the shoulder in order to prevent bearing deformation. (4) The guide and locating stopper shown in Fig. 2 are installed in order to apply press fitting accurately. The ball shown in Fig. 2 helps the jig hold the bearing and prevent roller inclination while facilitating mounting work. 5 6

5 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings 7. Inspection of Bearings Deformation, to a certain degree, due to heat treatment is inevitable, even though the outer ring of the drawn cup needle bearings is processed by precise deep drawing. However, once the bearing is pressed into the regular housing, this deformation is corrected and the bearing performs to its full potential. Therefore, it is not appropriate to measure the drawn cup outside diameter before mounting. orrect inspection is carried out according to the following procedures: (1) The bearing that is to be subject to testing is pressed into a ring gauge of given dimensions. (2) The inscribed circle diameter at the GO and NO-GO plug gauges is inspected. Table 5 Inspection Gauge Dimensions (General Metric) Table 6 Ring Gauge of Drawn up Needle Roller Bearings and Tolerance of Roller Inscribed ircle Diameter Units: mm (ISO Standards) Units: mm Metric inspection gauge dimensions are shown in Table 5. Table 6 shows tolerance for the roller inscribed circle diameter based on ISO standards. For bearings based on ISO standards, 1 is added at the end of the bearing number. Table 7 shows inch inspection gauge dimensions. Table 7 Inspection Gauge Dimensional Table (Inch) Units: mm Units: mm Nominal Roller Inscribed ircle Diameter, F w Bore Diameter of Ring Gauge F, FH, NF, NFH FJL FJ Plug Gauge Nominal Roller Inscribed ircle Diameter, F w Bore Diameter of Ring Gauge Tolerance for Roller Inscribed ircle Diameter, F w ( 1 ) GO Gauge NO-GO FJ, FJH, Gauge F, FH min max Nominal Roller Inscribed ircle Diameter, F w Bore Diameter of Ring Gauge JP GO Gauge Plug Gauge NO-GO Gauge Nominal Roller Inscribed ircle Diameter, F w Bore Diameter of Ring Gauge JH GO Gauge Plug Gauge NO-GO Gauge ( 1 / 8 ) ( 5 / 16 ) ( 5 / 32 ) ( 3 / 8 ) ( 3 / 16 ) ( 7 / 16 ) ( 1 / 4 ) ( 1 / 2 ) ( 5 / 16 ) ( 9 / 16 ) ( 3 / 8 ) ( 5 / 8 ) H ( 7 / 16 ) ( 11 / 16 ) ( 1 / 2 ) ( 3 / 4 ) FH H ( 9 / 16 ) ( 13 / 16 ) ( 5 / 8 ) ( 7 / 8 ) H ( 11 / 16 ) (1) NF ( 3 / 4 ) (1 1 / 8 ) H ( 13 / 16 ) (1 1 / 4 ) ( 7 / 8 ) (1 3 / 8 ) ( 15 / 16 ) (1) (1 1 / 16 ) (1 1 / 8 ) NFH (1 3 / 16 ) (1 1 / 4 ) NFH (1 5 / 16 ) (1 3 / 8 ) (1 1 / 2 ) (1 5 / 8 ) (1 3 / 4 ) (1 7 / 8 ) (2) Remarks This is the gauge dimension for inspection of minimum diameter, F w, of roller inscribed circle diameter. Note ( 1 ) When using a cylinder instead of an inner ring, F wmin is the diameter of the cylinder at which the internal clearance is zero in at least one radial direction. (F wmin is the minimum diameter of each inscribed circle diameter where deviation is suspected.) Remarks To measure the roller inscribed circle diameter, use the following plug gauges: GO gauge: The same dimensions as the minimum tolerance of the roller inscribed circle diameter, F w NO-GO gauge: The dimensions should be the maximum tolerance of roller inscribed circle diameter, F w, plus.2 mm 8

6 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings aged Inscribed ircle Diameter 3~16 mm ➃ ➅ ➇.25 r P max FJP ➇ FJP ➇ J ➃ FJ-58L ➅ FJ ➃ FJ-69W ➃ FJ ➃ DB ➅ J ➃ FJ ➃ J ➃ J ➃ JH ➃ FJ ➅ DB ➃ FJ-81W ➃ FJ ➅ FJL ➅ FJL ➅ FJL ➅ FJ ➅ FJL ➅ J-65A ➅ J ➅ J ➅ FJ-11W ➃ FJ-11WA ➃ FJ ➃ FJ-115L ➅ FJL ➃ FJL-112L ➅ FJL ➃ FJL ➃ J ➃.25 r P max JH ➃ FJ ➃ FJ-121W ➃ FJH ➃ FJH-1212W ➃ FJL-1212L ➅ FJL ➃ FJL ➃ FJL-1225L ➅ J ➃ JH ➃ JH ➃ FJ ➃ DB5133W ➅ FJ ➃ FJ ➃ FJL ➃ J ➃ JH ➃ FJ ➃ FJ ➃ FJ-1512W ➃ FJ ➃ FJL-151L ➅ FJL-1512L ➅ FJL ➃ FJL ➃ FJL-1525L ➅ J ➃ J ➃ JH ➃ JH ➃ FJ ➃ FJ ➃ 9 1

7 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings aged Inscribed ircle Diameter 16~28 mm ➃ ➅ ➆ ➇.25 r P max DB51613W ➅ FJL-1616L ➅ FJL-162L ➅ DB5168W ➆ DBP ➇ FJ ➃ FJ ➃ FJL ➃ FJL-172L ➅ FJL-1725L ➅ JH ➃ JH ➃ DB ➅ DB5181W ➅ FJ ➃ FJ ➃ FJL ➃ FJL ➃ FJL-1817L ➅ FJL ➃ FJL ➃ J ➃ J ➃ J ➃ FJ ➃ FJ ➃ DB525A ➅ FJ-22W ➃ FJ ➃ FJL-215L ➅ FJL ➃ FJL-225L ➅ FJL-225LW ➅ FJL-23L ➅ Load Ratings (N).25 r P max FJL-221L ➅ FJ ➃ FJ-2212W ➃ FJ ➃ FJ ➃ FJL-222L ➅ FJL-2225L ➅ FJL-223L ➅ DB ➅ JH ➃ DB5237W ➅ DB5245W ➅ FJ ➃ DB5259W ➅ FJ-252W ➃ FJ-252W ➃ FJ ➃ FJ ➃ FJL ➃ FJL ➃ FJL-2515L ➅ FJL ➃ FJL-2525L ➅ DB52514W ➅ FJL ➃ JH ➃ JH ➃ DB52519W ➅ DB52713W ➅ DB52822W ➅ FJ ➃ FJ-2816WA ➃ FJ ➃ FJ-282W ➃ 11 12

8 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings aged Inscribed ircle Diameter 28~43.7 mm ➃ ➄ ➅ ➆.25 r P max FJ ➃ DB52821W ➄ FJL-282L ➅ DB ➅ J ➃ J ➃ JH ➃ JH ➃ FJ ➃ DB ➅ DB5315W ➅ FJ ➃ FJL-325L ➅ DB ➅ FJ-316L ➅ FJ ➃ FJL-315L ➅ FJL-32L ➅ FJL-33L ➅ DB5312WA ➅ DB5318W ➅ J ➃ J ➃ DB5312A ➅ JH ➃ DB5327W ➅ DB53212W ➅ FJL ➃ FJL ➃ DBP ➇ DB5337W ➅ DB ➅ DB ➅ J ➃.25 r P max DB53522W ➅ FJ ➃ FJ ➃ DB5351AW ➃ DB ➃ FJ ➃ FJ-3526-OH ➃ FJL ➃ FJL ➃ FJ ➃ FJ ➃ DB53523W ➄ DB5358A ➅ DB ➅ FJL-352L ➅ FJL-3525L ➅ FJL-353L ➅ DB5375W ➅ DB ➅ J ➃ J ➃ DB ➅ DB5393W ➅ DB543WA ➅ FJ-42W ➃ FJL-415L ➅ FJ ➃ FJ ➃ FJ ➃ FJL-42L ➅ FJL-425L ➅ FJL-43L ➅ DB5415W ➅ DB5434W ➆ 13 14

9 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings aged Inscribed ircle Diameter 44.45~82 mm ➃ ➅ Full omplement Inscribed ircle Diameter 4~17 mm ➀ ➁.25 r P max J ➃ J ➃ FJ ➃ FJ ➃ FJ ➃ FJL-452L ➅ FJL-4525L ➅ FJL-453L ➅ DB ➅ DB5466WA ➅ DB5491W ➅ DB ➅ FJ-52L ➅ FJL-512L ➅ FJL-52L ➅ FJL-53L ➅ J ➃ DB5512A ➅ DB ➅ DB5551A ➅ FJ ➃ FJ ➃ DB5554W ➅ FJL-553L ➅ FJL-554L ➅ DB5555W ➅ DB ➅ DB5583W ➅ DB ➅.25 r P max DD ➁ F ➀ F ➀ F ➀ F ➀ F ➀ DD ➁ F ➀ F ➀ F ➀ F ➀ F ➀ F ➀ F-11-B ➀ F ➀ F ➀ F ➀ FH ➀ F ➀ NF ➀ NF ➀ F ➀ F ➀ F ➀ F ➀ F ➀ F ➀ F ➀ D ➀ DD ➁ F ➀ F ➀ F ➀ F ➀ 15 16

10 Drawn up Needle Roller Bearings Drawn up Needle Roller Bearings Full omplement Inscribed ircle Diameter 17~45 mm ➀ ➁ ➂.25 r P max F ➀ F ➀ F ➀ F-1816-OH ➀ DD ➁ DD ➁ DD ➂ F ➀ F ➀ DD ➁ F ➀ DD524A ➁ D ➀ F ➀ F ➀ F ➀ DD5221A ➁ F ➀ NFH-222A ➀ NFH-222A ➀ F ➀ F ➀ F ➀ F ➀ F ➀ D ➀ F ➀ F ➀ F ➀ F ➀ F-326-OH ➀ F-326R ➀ DD ➁ F ➀.25 r P max F ➀ F ➀ D ➀ FY ➁ F ➀ F ➀ F ➀ F ➀ F ➀ F ➀ F ➀ 17 18