Catalog Vong Bi Cau Ranh Sau SKF

8/10/2019 Catalog Vong Bi Cau Ranh Sau SKF

1/16

Single-Row Deep Groov

Ball Bearings, S-Typ

4

The MRC conrad ball bearing is a single-row radialdeep groove bearing with no filling notches. It cancarry significant radial loads, and, because of theuninterrupted raceway grooves and the high degreeof conformity between balls and raceways, it cancarry substantial thrust loads in either direction, evenat very high speeds. Single-row deep groove ballbearings are offered open or with single or doubleshields or seals, as well as with snap rings in variouscombinations.

Cage Types and Materials

This type of bearing is supplied with a pressed steecage as standard; however, for special requirementit can be supplied with a two-piece riveted machinecage of phenolic composition or bronze material.

Size

30

R

1800S

1900S

100S

100KS

200S

300S

400S

Extra Small

Small Inch-Size

Thin Section

Extremely Light

Narrow-Type Light

Extra Light

Light

Medium

Heavy

42

43

44

45

46

47

48

49

50

Series Page

Cartridge Type

Equivalent Load and Life

Life Calculation Examples

51

52

53

Hybrid Bearings 54


2/16

3435

36

373839

45

6

789

1619

19

222226

56

6

778

.30

.30

.30

.30

.30

.64

4596

96

110110161

1 4702 210

2 210

3 2503 2504 620

600950

950

1 3601 3601 960

43 00036 000

36 000

36 00036 00028 000

50 00043 000

43 000

43 00043 00034 000

30 00026 000

26 000

23 00023 00020 000

MRC Bearing Services

30 Series

Extra Small Size

42

These single-row radial conrad-type bearings have 4mm to 9 mm bores (approximately to ), and aredesigned for very small shafts. They are suitable forhigh speed fractional horsepower motors and smallturbines. MRC offers open, shielded, and sealedtypes. Some sizes are available in stainless steel.

30 Series supplied with ABMA CO radial clearanceunless otherwise specified.

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf

Basic Radial Load Rating Speed Rating2)

StaticC0

N lbf

Open and ShieldedGrease Oil

RPM RPM

Single andDouble Sealed

Grease

RPM

.1575

.1969

.2362

.2756

.3150

.3543

.6299

.7480

.7480

.8661

.86611.0236

.1969

.2362

.2362

.2756

.2756

.3150

.012

.012

.012

.012

.012

.025

.07

.15

.15

.17

.17

.25

330497

497

731731

1 040

135214

214

306306441

1) Fillet radius indicates maximum fillet radius on shaft or in housing which bearing corner will clear.2) Listed values are for pressed steel or polyamide cage, ABEC-1.

For phenolic composition cage, multiply by 1.66 for grease and 2.00 for oil. For machined bronze cage, multiply by 1.25 for grease and 1.50 for oil. For phenolic compositioncage, ABEC-5 or 7, multiply by 2.30 for grease and 2.80 for oil. The speed rating adjustment factors have been determined through historical application and practice. For amore complete explanation, see page 274.

3) Rating for one million revolutions or 500 hours at 33 RPM.


3/16

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Shielded orSealed

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf

Basic Radial Load Rating

StaticC0

N lbf


RPM RPM

Single anDouble Sea

Grease

RPM

Plain

mm in

ZD2

mm in

Speed Rating2)

R-2R-2-A

R-3

R-4R-4-AR-6

R-8R-10R-12

R-14R-16R-18

R-20R-24

3.23.2

4.8

6.46.49.5

12.715.919.1

22.225.428.6

31.838.1

9.512.7

12.7

15.919.122.2

28.634.941.3

47.650.854.0

57.266.7

4.04.4

4.0

5.05.65.6

6.47.17.9

9.59.59.5

9.511.1

4.04.4

5.0

5.07.17.1

7.98.7

11.1

12.712.712.7

12.714.3

.30

.30

.30

.30

.41

.41

.41

.79

.79

.79

.79

.79

.79

.79

1919

39

4571

110

181226361

406406510

613755

312312

956

1 4802 8103 320

5 0706 0509 360

10 10010 10012 500

14 00016 800

120120

490

6201 1601 340

2 4003 2505 100

5 8506 0007 500

9 30011 800

75 00075 000

57 000

44 00039 00031 000

24 00018 00016 000

14 00013 00011 000

11 0009 000

91 00091 000

69 000

54 00048 00038 000

29 00022 00019 000

17 00016 00014 000

13 00011 000

52 00052 000

40 000

31 00027 00021 000

16 00013 00011 000

9 6009 0007 900

7 5006 200

.1250

.1250

.1875

.2500

.2500

.3750

.5000

.6250

.7500

.87501.00001.1250

1.25001.5000

.3750

.5000

.5000

.6250

.7500

.8750

1.12501.37501.6250

1.87502.00002.1250

2.25002.6250

.1562

.1719

.1562

.1960

.2188

.2188

.2500

.2812

.3125

.3750

.3750

.3750

.3750

.4375

.1562

.1719

.1960

.1960

.2812

.2812

.3125

.3438

.4375

.5000

.5000

.5000

.5000

.5625

.012

.012

.012

.012

.016

.016

.016

.031

.031

.031

.031

.031

.031

.031

.03

.03

.06

.07

.11

.17

.28

.35

.56

.63

.63

.79

.951.17

7070

215

332632746

1 1401 3602 100

2 2702 2702 810

3 1503 780

2727

110

139261301

540731

1 150

1 3201 3501 690

2 0902 650

R Series Small Inch-Siz

4

R series bearings are single-row radial conrad-typebearings that are available in inch sizes for shaftsfrom to 1 in diameter. Open, shielded, andsealed types are available, and many sizes areavailable in stainless steel.R Series supplied with ABMA CO radial clearance

unless otherwise specified.


For phenolic composition cage, multiply by 1.66 for grease and 2.00 for oil. For machined bronze cage, multiply by 1.25 for grease and 1.50 for oil. For phenolic compositiocage, ABEC-5 or 7, multiply by 2.30 for grease and 2.80 for oil. The speed rating adjustment factors have been determined through historical application and practice. For amore complete explanation, see page 274.


Width B


4/16

MRC Bearing Services1800-S Thin Section Series

44

1800-S Series bearings are single-row radial conrad-type bearings that can accommodate light radialloads, two-directional thrust loads, or a combinationof both. They are designed for applications wherespace or weight is very limited.The 1800-S Series is supplied with an ABMA CO Radial internal clearance

unless otherwise specified.

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf


StaticC0

N lbf


RPM RPM


Grease

RPM

1800S1801S1802S

1803S1804S1805S

1806S1807S1808S

1809S1810S1811S

1812S1813S1814S

1815S1816S1817S

1818S

1819S1820S

1821S1822S1824S4)

1826S4)

1828S4)

1830S4)

1832S4)

1834S4)

1836S4)

1838S4)

1840S4)

1844S4)

1848S4)

1852S4)

1856S4)

1860S4)

1864S4)

1868S4)

1872S4)

1876S4)

1880S4)

1884S4)

1888S4)

1892S4)

1896S4)

101215

172025

303540

455055

606570

758085

90

95100

105110120

130140150

160170180

190200220

240260

280

300320340

360380400

420440460

480

192124

263237

424752

586572

788590

95100110

115

120125

130140150

165175190

200215225

240250270

300320

350

380400420

440480500

520540580

600

555

577

777

779

101010

101013

13

1313

131616

181820

202222

242424

2828

33

383838

384646

464656

56

.30

.30

.30

.30.30

.30

.30

.30

.30

.30

.30

.30

.30

.60

.60

.60

.601.0

1.0

1.01.0

1.01.01.0

1.01.01.0

1.01.01.0

1.51.51.5

2.02.0

2.0

2.02.02.0

2.02.02.0

2.02.02.5

2.5

626880

91141184

208233257

315347454

499679741

803864

1 230

1 280

1 3301 380

1 4801 9102 060

2 6602 8703 540

3 6904 5504 730

5 6905 9106 370

8 6709 330

11 500

14 20014 70015 900

16 40022 70023 700

24 60025 50033 300

34 700

1 8201 9002 080

2 2503 5104 360

4 4904 7504 940

6 0506 2408 320

8 71011 70012 100

12 50013 00019 500

19 500

19 90020 300

20 80028 10029 100

37 70039 00048 800

49 40061 80062 400

74 10076 10078 000

108 000111 000

138 000

172 000172 000178 000

182 000242 000247 000

251 000255 000312 000

325 000

9301 0401 250

1 4602 2402 900

3 4003 8004 150

5 1005 5007 350

8 00011 00011 800

12 90013 70019 600

20 400

21 20022 000

23 60030 50032 500

43 00046 50057 000

60 00073 50076 500

91 50095 000

102 000

140 000150 000

183 000

228 000236 000255 000

260 000365 000380 000

390 000405 000530 000

560 000

36 00032 00028 000

24 00019 00017 000

15 00013 00011 000

9 5009 0008 500

7 5007 0006 700

6 3006 0005 300

5 300

5 0004 800

4 5004 3003 800

3 6003 4003 000

2 8002 6002 400

2 2002 2001 900

1 8001 700

1 600

1 4001 3001 200

1 1001 0001 000

950900900

850

43 00038 00034 000

30 00024 00020 000

18 00016 00014 000

12 00011 00010 000

9 0008 5008 000

7 5007 0006 300

6 300

6 0005 600

5 3005 0004 500

4 3004 0003 600

3 4003 2003 000

2 8002 8002 400

2 2002 000

1 900

1 7001 6001 500

1 4001 3001 300

1 2001 1001 100

1 000

20 00019 00017 000

16 00013 00011 000

9 5008 0007 500

6 7006 0005 180

4 8004 5004 300

4 0003 6003 400

3 200

3 0003 000

2 8002 6002 400

2 2002 000

.3937

.4724

.5906

.6693.7874

.9843

1.18111.37801.5748

1.77171.96852.1654

2.36222.55912.7559

2.95283.14963.3465

3.5433

3.74023.9370

4.13394.33074.7244

5.11815.51185.9055

6.29926.69297.0866

7.48037.87408.6614

9.448810.2362

11.0236

11.811012.598413.3858

14.173214.960615.7480

16.535417.322818.1102

18.8976

.7480

.8268

.9449

1.02361.25981.4567

1.65351.85042.0472

2.28352.55912.8346

3.07093.34653.5433

3.74023.93704.3307

4.5276

4.72444.9213

5.11815.51185.9055

6.49616.88987.4803

7.87408.46468.8583

9.44889.8425

10.6299

11.811012.5984

13.7795

14.960615.748016.5354

17.322818.897619.6850

20.472421.259822.8346

23.6220

.1969

.1969

.1969

.1969.2756

.2756

.2756

.2756

.2756

.2756

.2756

.3543

.3937

.3937

.3937

.3937

.3937

.5118

.5118

.5118.5118

.5118

.6299

.6299

.7087

.7087

.7874

.7874

.8661

.8661

.9449

.9449

.9449

1.10241.1024

1.2992

1.49611.49611.4961

1.49611.81101.8110

1.81101.81102.2047

2.2047

.012

.012

.012

.012.012

.012

.012

.012

.012

.012

.012

.012

.012

.025

.025

.025

.025

.040

.040

.040.040

.040

.040

.040

.040

.040

.040

.040

.040

.040

.060

.060

.060

.080

.080

.080

.080

.080

.080

.080

.080

.080

.080

.080

.100

.100

.10

.11

.12

.14.22

.28

.32

.36

.40

.49

.54

.70

.771.051.15

1.241.321.90

1.98

2.062.14

2.292.953.19

4.134.465.49

5.717.067.34

8.819.179.87

13.414.5

17.8

22.022.924.6

25.535.336.7

38.139.551.7

53.7

410427468

505790980

1 0101 0701 110

1 3601 4001 870

1 9602 6302 720

2 8102 9204 380

4 380

4 4704 560

4 6806 3206 540

8 4808 770

11 000

11 10013 90014 000

16 70017 10017 500

24 30025 000

31 000

38 70038 70040 000

40 90054 40055 500

56 40057 30070 100

73 100

209234281

328504652

764854933

1 1501 2401 650

1 8002 4702 650

2 9003 0804 410

4 590

4 7704 950

5 3106 8607 310

9 67010 50012 800

13 50016 50017 200

20 60021 40022 900

31 50033 700

41 100

51 30053 10057 300

58 50082 10085 400

87 70091 000

119 000

126 000

1) Fillet radius indicates maximum fillet radius on shaft or in housing which bearing corner will clear.2) Listed values are for pressed steel cage for 1800S through 1828S and 1834S and 1856S. All others for outer land guided machined bronze.

The values have been determined through historical application and practice. For a more complete explanation, see page 274.3) Rating for one million revolutions or 500 hours at 33 RPM.4) Typically non-stocked sizes, please check availability before designing into equipment.


5/16

1900-S Series Extremely Light Serie

4

1900-S Series bearings are single-row radial conradtype bearings that can accommodate light radialloads, two-directional thrust loads, or a combinationof both. They are designed for applications wherea lack of space or limitations on weight require abearing with a thinner section than 100-KS Series

bearings. Some sizes are available with shields orseals.

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf


StaticC0

N lbf


RPM RPM

Single anDouble Sea

Grease

RPM

1900S1901S

1902S

1903S1904S1905S

1906S1907S1908S

1909S1910S1911S

1912S1913S1914S

1915S1916S1917S

1918S1919S1920S

1921S1922S1924S

1926S4)

1928S4)

1930S4)

1932S4)

1934S4)

1936S4)

1938S4)

1940S4)

1944S4)

1948S4)1952S4)

1956S4)

1960S4)

1964S4)

1968S4)

1972S4)

1976S4)

1980S4)

1984S4)

1988S4)

1992S4)

1012

15

172025

303540

455055

606570

758085

9095

100

105110120

130140150

160170180

190200220

240260280

300320340

360380400

420440460

2224

28

303742

475562

687280

8590

100

105110120

125130140

145150165

180190210

220230250

260280300

320360380

420440460

480520540

560600620

66

7

799

91012

121213

131316

161618

181820

202022

242428

282833

333838

384646

565656

566565

657474

.30

.30

.30

.30

.30

.30

.30

.64

.64

.64

.641.0

1.01.01.0

1.01.01.0

1.01.01.0

1.01.01.0

1.51.52.0

2.02.02.0

2.02.02.0

2.02.02.0

3.03.03.0

3.04.04.0

4.04.04.0

84103

142

155252271

317432637

683728864

864968

1 300

1 3701 4501 810

1 9202 0252 550

2 7702 7703 460

4 1004 3205 670

6 0006 3308 060

8 06010 20010 800

11 90016 40017 300

22 70024 00025 300

26 70032 40034 100

35 80043 10045 400

2 5102 910

4 030

4 3606 3706 630

7 2809 560

13 800

14 00014 60016 500

16 50017 40023 800

24 20025 10031 900

32 50033 80042 300

44 20043 60055 300

65 00066 30088 400

92 30093 600

119 000

117 000148 000151 000

159 000212 000216 000

270 000276 000281 000

291 000338 000345 000

351 000410 000423 000

1 1201 500

2 040

2 3203 6504 150

5 0006 800

10 000

10 80011 80014 000

14 30016 00021 200

22 40024 00030 000

31 50033 50041 500

44 00044 00057 000

67 00071 00093 000

98 000104 000132 000

134 000166 000176 000

196 000270 000285 000

375 000390 000415 000

440 000530 000560 000

585 000710 000750 000

34 00030 000

24 000

22 00018 00016 000

14 00011 00010 000

9 0008 5008 000

7 5006 7006 300

6 0005 6005 300

5 0004 8004 500

4 3004 0003 600

3 4003 2002 800

2 6002 4002 200

2 2002 0001 900

1 8001 6001 500

1 3001 2001 100

1 1001 000

950

900900850

40 00036 000

30 000

28 00022 00019 000

17 00014 00013 000

11 00010 0009 500

9 0008 0007 500

7 0006 7006 300

6 0005 6005 300

5 0004 8004 300

4 0003 8003 400

3 2003 0002 800

2 8002 6002 400

2 2001 9001 800

1 6001 5001 400

1 4001 3001 200

1 1001 1001 000

19 00018 000

16 000

14 00012 00010 000

8 5007 5006 700

6 0005 6005 000

4 5004 3004 000

3 6003 4003 200

3 1002 9002 700

2 6002 5002 300

2 1002 0001 800

1 7001 6001 500

1 4001 3001 200

1 1001 000950

800750700

700650600

550550550

.3937

.4724

.5906

.6693

.7874

.9843

1.18111.37801.5748

1.77171.96852.1654

2.36222.55912.7559

2.95283.14963.3465

3.54333.74023.9370

4.13394.33074.7244

5.11815.51185.9055

6.29926.69297.0866

7.48037.87408.6614

9.448810.236211.0236

11.811012.598413.3858

14.173214.960615.7480

16.535417.322818.1102

.8661

.9449

1.1024

1.18111.45671.6535

1.85042.16542.4409

2.67722.83463.1496

3.34653.54333.9370

4.13394.33074.7244

4.92135.11815.5118

5.70875.90556.4961

7.08667.48038.2677

8.66149.05519.8425

10.236211.023611.8110

12.598414.173214.9606

16.535417.322818.1102

18.897620.472421.2598

22.047223.622024.4094

.2362

.2362

.2756

.2756

.3543

.3543

.3543

.3937

.4724

.4724

.4724

.5118

.5118

.5118

.6299

.6299

.6299

.7087

.7087

.7087

.7874

.7874

.7874

.8661

.9449

.94491.1024

1.10241.10241.2992

1.29921.49611.4961

1.49611.81101.8110

2.20472.20472.2047

2.20472.55912.5591

2.55912.91342.9134

.012

.012

.012

.012

.012

.012

.012

.025

.025

.025

.025

.040

.040

.040

.040

.040

.040

.040

.040

.040

.040

.040

.040

.040

.060

.060

.080

.080

.080

.080

.080

.080

.080

.080.080

.080

.120

.120

.120

.120

.160

.160

.160

.160

.160

.13

.16

.22

.24

.39

.42

.49

.67

.99

1.061.131.34

1.341.502.01

2.132.252.81

2.973.143.96

4.184.185.36

6.356.708.78

9.309.8212.5

12.515.816.7

18.525.426.8

35.137.239.3

41.350.252.8

55.566.870.3

565655

906

9801 4301 490

1 6402 1503 100

3 1503 2803 710

3 7103 9105 350

5 4405 6407 170

7 3107 6009 510

9 9409 800

12 400

14 60014 90019 900

20 70021 00026 800

26 30033 30033 900

35 80047 70048 600

60 70062 10063 200

65 40076 00077 000

78 90092 20095 100

252337

459

522821933

1 1201 5302 250

2 4302 6503 150

3 2103 6004 770

5 0405 4006 740

7 0807 5309 330

9 8909 890

12 800

15 10016 00020 900

22 00023 40029 700

30 10037 30039 600

44 10060 70064 100

84 30087 70093 300

98 900119 000126 000

132 000160 000169 000



3)

Rating for one million revolutions or 500 hours at 33

RPM.4) Typically non-stocked sizes, please check availability before designing into equipment.


6/16


7/16

100-KS Extra Light Serie

4

The 100-KS Extra Light Series consists of single-rowradial conrad-type bearings made with bores from 1mm to 320 mm for light to moderate radial loads,two-directional thrust loads, or a combination of botwhere space is somewhat limited. This series isavailable in plain, shielded, or sealed types, as well

as with snap-rings.

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf


StaticC0

N lbf


RPM RPM

Single anDouble Sea

Grease

RPM

100-KS101-KS

102-KS

103-KS104-KS105-KS

106-KS107-KS108-KS

109-KS110-KS111-KS

112-KS113-KS114-KS

115-KS116-KS117-KS

118-KS119-KS120-KS

121-KS122-KS124-KS

126-KS128-KS4)

130-KS4)

132-KS4)

134-KS4)

136-KS4)

138-KS4)

140-KS4)

144-KS4)

148-KS4)152-KS4)

156-KS4)

160-KS4)

164-KS4)

1012

15

172025

303540

455055

606570

758085

9095

100

105110120

130140150

160170180

190200220

240260280

300320

2628

32

354247

556268

758090

95100110

115125130

140145150

160170180

200210225

240260280

290310340

360400420

460480

88

9

101212

131415

161618

181820

202222

242424

262828

333335

384246

465156

566565

7474

.30

.30

.30

.30

.64

.64

1.01.01.0

1.01.01.0

1.01.01.0

1.01.01.0

1.51.51.5

2.02.02.0

2.02.02.0

2.02.02.0

2.02.02.5

2.53.03.0

3.03.0

181181

206

226361458

561691909

1 0901 1801 390

1 6101 7302 100

2 2602 6502 860

3 2803 5303 530

4 3304 6605 000

5 9606 9008 385

9 03011 80011 400

13 40015 90018 600

19 50023 90025 700

31 70034 000

4 6205 070

5 590

6 0509 360

11 200

13 30015 80020 800

23 40024 70028 100

32 50033 80041 000

42 30050 70052 700

61 80063 70063 700

79 30081 80085 200

106 000111 000125 000

143 000168 000190 000

195 000216 000247 000

255 000291 000302 000

358 000371 000

1 9602 360

2 850

3 2505 0006 550

8 30010 20011 600

16 60018 00021 600

25 00027 00032 500

35 50041 50045 000

51 00054 00054 000

65 50073 50080 000

100 000108 000125 000

143 000173 000200 000

216 000245 000290 000

315 000375 000405 000

500 000540 000

30 00026 000

22 000

19 00017 00015 000

12 00010 0009 500

9 0008 5007 500

6 7006 3006 000

5 6005 3005 000

4 8004 5004 300

4 0003 8003 400

3 2003 0002 600

2 4002 2002 000

2 0001 9001 800

1 7001 5001 400

1 2001 100

36 00032 000

28 000

24 00020 00018 000

15 00013 00012 000

11 00010 0009 000

8 0007 5007 000

6 7006 3006 000

5 6005 3005 000

4 8004 5004 000

3 8003 6003 200

3 0002 8002 600

2 6002 4002 200

2 0001 8001 700

1 5001 400

19 00017 000

14 000

13 00011 0009 500

8 0007 0006 300

5 6005 0004 500

4 3004 0003 600

3 4003 2003 000

2 8002 8002 600

2 4002 4002 200

2 0001 8001 700

1 6001 5001 400

1 4001 3001 100

1 000940890

780730

.3937

.4724

.5906

.6693

.7874

.9843

1.18111.37801.5748

1.77171.96852.1654

2.36222.55912.7559

2.95283.14963.3465

3.54333.74023.9370

4.13394.33074.7244

5.11815.51185.9055

6.29926.69297.0866

7.48037.87408.6614

9.448810.236211.0236

11.811012.5984

1.02361.1024

1.2598

1.37801.65351.8504

2.16542.44092.6772

2.95283.14963.5433

3.74023.93704.3307

4.52764.92135.1181

5.51185.70875.9055

6.29926.69297.0866

7.87408.26778.8583

9.448810.236211.0236

11.417312.204713.3868

14.173215.748016.5354

18.110218.8976

.3150

.3150

.3543

.3937

.4724

.4724

.5118

.5512

.5906

.6299

.6299

.7087

.7087

.7087

.7874

.7874

.8661

.8661

.9449

.9449

.9449

1.02361.10241.1024

1.29921.29921.3780

1.49611.65351.8110

1.81102.00792.2047

2.20472.55912.5591

2.91342.9134

.012

.012

.012

.012

.025

.025

.04

.04

.04

.04

.04

.04

.04

.04

.04

.04

.04

.04

.06

.06

.06

.08

.08

.08

.08

.08

.08

.08

.08

.08

.08

.08

.10

.10.12

.12

.12

.12

.28

.28

.32

.35

.56

.71

.871.071.41

1.691.832.16

2.492.683.25

3.504.114.43

5.085.475.47

6.727.237.75

9.2410.713.0

14.018.317.7

20.824.628.9

30.237.039.9

49.252.7

1 0401 140

1 260

1 3602 1002 520

2 9903 5704 680

5 2705 5606 320

7 3107 6009 220

9 51011 40011 800

13 90014 30014 300

17 80018 40019 100

23 80025 00028 100

32 10037 80042 700

43 80048 60055 500

57 30065 40067 900

80 50083 400

440530

640

7301 1201 470

1 8702 2902 610

3 7304 0504 880

5 6206 0707 310

7 9709 330

10 100

11 50012 10012 100

14 70016 50018 000

22 50024 30028 100

32 10038 90045 000

48 60055 10065 200

70 80084 30091 000

112 000121 000



3) Rating for one million revolutions or 500 hours at 33 RPM.4) Typically non-stocked sizes, please check availability before designing into equipment.

KSFOne Shield

KSZOne Seal

KSFFTwo Shields

KSZZTwo Seals

KSFZShield &

Seal

KSGSnap-Ring

KSFGOne Shield

& Snap-Ring

KSZGSeal &

Snap-Ring

KSFFGTwo Shields& Snap-Ring

KSZZGTwo Seals &Snap-Ring


8/16

MRC Bearing Services200-S Light Series

48

200-S Light Series bearings are single-row radialconrad-type bearings made with bores from 10 mmto 120 mm. They are used in applications withmoderate to heavy radial loads, two-directionalthrust loads, or a combination of both.

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf


StaticC0

N lbf


RPM RPM


Grease

RPM

200-S201-S

202-S

203-S204-S205-S

206-S207-S208-S

209-S210-S211-S

212-S213-S214-S

215-S216-S217-S

218-S219-S220-S

221-S222-S224-S

1012

15

172025

303540

455055

606570

758085

9095

100

105110120

3032

35

404752

627280

8590

100

110120125

130140150

160170180

190200215

910

11

121415

161718

192021

222324

252628

303234

363840

.64

.64

.64

.641.01.0

1.01.01.0

1.01.01.5

1.51.51.5

1.52.02.0

2.02.02.0

2.02.02.0

181252

290

361503568

8191 1101 360

1 5101 6102 040

2 2802 7703 060

3 3503 6304 260

5 0505 6706 450

7 2808 1908 970

5 0706 890

7 800

9 56012 70014 000

19 50025 50030 700

33 20035 10043 600

47 50055 90060 500

66 30072 80083 200

95 600108 000124 000

133 000143 000146 000

2 3603 100

3 250

4 7506 5507 800

11 20015 30019 000

21 60023 20029 000

32 50040 50045 000

49 00053 00064 000

73 50081 50093 000

104 000118 000118 000

24 00022 000

19 000

17 00015 00012 000

10 0009 0008 500

7 5007 0006 300

6 0005 3005 000

4 8004 5004 300

3 8003 6003 400

3 2003 0002 800

30 00028 000

24 000

20 00018 00015 000

13 00011 00010 000

9 0008 5007 500

7 0006 3006 000

5 6005 3005 000

4 5004 3004 000

3 8003 6003 400

17 00015 000

13 000

12 00010 0008 500

7 5006 3005 600

5 0004 8004 300

4 0003 6003 400

3 2003 0002 800

2 6002 4002 400

2 2002 0001 900

.3937

.4724

.5906

.6693

.7874

.9843

1.18111.37801.5748

1.77171.96852.1654

2.36222.55912.7559

2.95283.14963.3465

3.54333.74023.9370

4.13394.33074.7244

1.18111.2598

1.3780

1.57481.85042.0472

2.44092.83463.1496

3.34653.54333.9370

4.33074.72444.9213

5.11815.51185.9055

6.29926.69297.0866

7.48037.87408.4646

.3543

.3937

.4331

.4724

.5512

.5906

.6299

.6693

.7087

.7480

.7874

.8268

.8661

.9055

.9449

.98431.02361.1024

1.18111.25981.3386

1.41731.49611.5748

.025

.025

.025

.025

.04

.04

.04

.04

.04

.04

.04

.06

.06

.06

.06

.06

.08

.08

.08

.08

.08

.08

.08

.08

.28

.39

.45

.56

.78

.88

1.271.722.11

2.352.503.16

3.534.305.18

5.205.636.60

7.838.79

10.00

11.312.713.9

1 1401 550

1 750

2 1502 8603 150

4 3805 7306 900

7 4607 8909 800

10 70012 60013 600

14 90016 40018 700

21 50024 30027 900

29 90032 10032 800

531697

843

1 0701 4701 750

2 5203 4404 270

4 8605 2206 520

7 3109 110

10 100

11 00011 90014 400

16 50018 30020 900

23 40026 50026 500




SFOne Shield

SZOne Seal

SFFTwo Shields

SZZTwo Seals

SFZShield &

Seal

SGSnap-Ring

SFGShield &

Snap-Ring

SFFGTwo Shields

& Snap-Ring

SZGOne Seal &Snap-Ring

SZZGTwo Seals& Snap-Ring


9/16

300-S Medium Serie

4

300-S Medium Series bearings are used with heavyradial loads, two-directional thrust loads, or acombination of both.

SFOne Shield

SZOne Seal

SFFTwo Shields

SZZTwo Seals

SFZShield &

Seal

SGSnap-Ring

SFGShield &

Snap-Ring

SFFGTwo Shields

& Snap-Ring



300-S301-S

302-S

303-S304-S305-S

306-S307-S308-S

309-S310-S311-S

312-S313-S314-S

315-S316-S317-S

318-S319-S320-S

321-S322-S324-S

1012

15

172025

303540

455055

606570

758085

9095

100

105110120

.3937

.4724

.5906

.6693

.7874

.9843

1.18111.37801.5748

1.77171.96852.1654

2.36222.55912.7559

2.95283.14963.3465

3.54333.74023.9370

4.13394.33074.7244

3537

42

475262

728090

100110120

130140150

160170180

190200215

225240260

1.37801.4567

1.6535

1.85042.04722.4409

2.83463.14963.5433

3.93704.33074.7244

5.11815.51185.9055

6.29926.69297.0866

7.48037.87408.4646

8.85839.4488

10.2362

1112

13

141517

192123

252729

313335

373941

434547

495055

.4331

.4724

.5118

.5512

.5906

.6693

.7480

.8268

.9055

.98431.06301.1417

1.22051.29921.3780

1.45671.53541.6142

1.69291.77171.8504

1.92911.96852.1654

.641.0

1.0

1.01.01.0

1.01.51.5

1.52.02.0

2.02.02.0

2.02.02.5

2.52.52.5

2.52.52.5

.025

.04

.04

.04

.04

.04

.04

.06

.06

.06

.08

.08

.08

.08

.08

.08

.08

.10

.10

.10

.10

.10

.10

.10

303381

439

535632864

1 2101 4601 820

2 4402 9003 410

3 9504 5405 160

5 8206 5157 290

8 0608 900

10 600

11 60013 60013 600

.47

.59

.68

.83

.981.34

1.882.262.82

3.624.505.28

6.137.038.00

9.0310.111.3

12.513.816.5

18.021.121.1

8 0609 750

11 400

13 50015 90021 200

28 10033 20041 000

52 70061 80071 500

81 90092 300

104 000

114 000124 000133 000

143 000153 000174 000

182 000203 000208 000

1 8102 190

2 560

3 0303 5704 760

6 3207 4609 220

11 90013 90016 100

18 40020 80023 400

25 60027 90029 900

32 10034 40039 100

40 80045 60046 700

3 4004 150

5 400

6 5507 800

10 800

16 00019 00024 000

31 50038 00045 000

52 00060 00068 000

76 50086 50096 500

108 000118 000140 000

153 000180 000186 000

764933

1 210

1 4701 7502 430

3 6004 2705 400

7 0808 540

10 100

11 70013 50015 300

17 20019 40021 700

24 30026 50031 500

34 40040 50041 800

20 00019 000

17 000

16 00013 00011 000

9 0008 5007 500

6 7006 3005 600

5 0004 8004 500

4 3003 8003 600

3 4003 2003 000

2 8002 6002 400

26 00024 000

20 000

19 00016 00014 000

11 00010 0009 000

8 0007 5006 700

6 0005 6005 300

5 0004 5004 300

4 0003 8003 600

3 4003 2003 000

15 00014 000

12 000

11 0009 5007 500

6 3006 0005 000

4 5004 3003 800

3 4003 2003 000

2 8002 6002 400

2 4002 2002 100

2 0001 800

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf

StaticC0

N lbf


RPM RPM

Single anDouble Sea

Grease

RPM






10/16

MRC Bearing Services400-S Heavy Series

50

This series is made up of single-row radial conrad-type bearings made with bores ranging from 17mm to 110 mm. They are used in applications withvery heavy radial loads, two-directional thrustloads, or a combination of both.

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf


StaticC0

N lbf


RPM RPM


Grease

RPM

403-S404-S

405-S

406-S407-S408-S

409-S410-S411-S

412-S413-S414-S

415-S416-S417-S

418-S419-S4)

420-S4)

421-S4)

422-S4)

1720

25

303540

455055

606570

758085

9095

100

105110

6272

80

90100110

120130140

150160180

190200210

225250265

290320

1719

21

232527

293133

353742

454852

545560

6570

1.01.0

1.5

1.51.52.0

2.02.02.0

2.02.02.5

2.52.53.0

3.03.03.0

3.03.0

9681 370

1 590

1 9502 5402 980

3 7104 5205 100

5 7106 3708 510

9 35010 20011 000

12 80013 80015 900

18 10020 300

22 90030 700

35 800

43 60055 30063 700

76 10087 10099 500

108 000119 000143 000

153 000163 000174 000

186 000203 000225 000

247 000270 000

10 80015 000

19 300

23 60031 00036 500

45 00052 00062 000

69 50078 000

104 000

114 000125 000137 000

150 000173 000200 000

228 000260 000

12 00010 000

9 000

8 5007 0006 700

6 0005 2005 000

4 8004 5003 800

3 6003 4003 200

3 0002 7002 500

2 4002 100

15 00013 000

11 000

10 0008 5008 000

7 0006 3006 000

5 6005 3004 500

4 3004 0003 800

3 6003 3003 100

2 9002 600

8 5007 300

6 400

5 6004 9004 400

4 0003 7003 400

3 1002 9002 600

2 5002 3002 200

2 1001 9001 800

1 6001 500

.6693

.7874

.9843

1.18111.37801.5748

1.77171.96852.1654

2.36222.55912.7559

2.95283.14963.3465

3.54333.74023.9370

4.13394.3307

2.44092.8346

3.1496

3.54333.93704.3307

4.72445.11815.5118

5.90556.29927.0866

7.48037.87408.2677

8.85839.8425

10.4331

11.417312.5984

.6693

.7480

.8268

.9055

.98431.0630

1.14171.22051.2992

1.37801.45671.6535

1.77171.88982.0472

2.12602.16542.3622

2.55912.7559

.04

.04

.06

.06

.06

.08

.08

.08

.08

.08

.08

.10

.10

.10

.12

.12

.12

.12

.12

.12

1.502.12

2.47

3.023.944.62

5.757.007.90

8.869.87

13.2

14.515.817.1

19.921.424.6

28.031.6

5 1506 900

8 050

9 80012 40014 300

17 10019 60022 400

24 30026 80032 100

34 40036 60039 100

41 80045 60050 600

55 50060 700

2 4303 370

4 340

5 3106 9708 210

10 10011 70013 900

15 60017 50023 400

25 60028 10030 800

33 70038 90045 000

51 30058 500



3) Rating for one million revolutions or 500 hours at 33 RPM.4) Typically non-stocked sizes, please check availability before designing into equipment.

SFOne Shield

SZOne Seal

SFFTwo Shields

SZZTwo Seals

SFZShield &

Seal

SGSnap-Ring

SFGShield &

Snap-Ring

SFFGTwo Shields

& Snap-Ring




11/16

Cartridge-Type Bearings Type

SFFC, SZZC, SLL

5

Cartridge-type bearings have an extra large greasechamber packed with high quality lubricant. Forapplications where space for a lubrication system islimited or conditions demand a larger grease supplinside bearing.Bearings designated SFFC have non-removable metal shields. Many size

are available with removable shields (SLLC) or synthetic rubber seals(SZZC).

MRCBearingNumber

Bore

d

mm in

OutsideDiameterD

mm in

Width

B

mm in

FilletRadius1)

ramm in

ZD2

mm in

DynamicC3)

N lbf


StaticC0

N lbf


RPM RPM

Single anDouble Sea

Grease

RPM

200-SFFC201-SFFC

202-SFFC203-SFFC204-SFFC



211-SFFC213-SFFC214-SFFC216-SFFC






320-SFFC

1012

151720

253035

404550

55657080

202530

354045

505560

657075

808590

100

3032

354047

526272

808590

100120125140

526272

8090

100

110120130

140150160

170180190

215

14.2915.88

15.8817.4620.64

20.6423.8126.99

30.1630.1630.16

33.3438.1039.6944.45

22.2325.4030.16

34.9336.5139.69

44.4549.2153.98

58.7463.5068.26

68.2673.0373.03

82.55

.64

.64

.64

.641.0

1.01.01.0

1.01.01.0

1.51.51.52.0

1.01.01.0

1.51.51.5

2.02.02.0

2.02.02.0

2.02.52.5

2.5

181252

290361503

568819

1 140

1 4501 6401 610

2 0403 0503 0503 630

632864

1 290

1 5902 0202 330

2 9003 4103 950

4 5305 1606 530

7 2807 2808 060

11 600

5 0706 760

7 6109 560

13 000

15 10020 80026 500

32 50036 40035 100

39 70062 40062 40078 000

15 90021 00029 600

36 40044 20052 000

61 80071 50081 900

92 300104 000124 000

133 000133 000143 000

182 000

2 4003 000

3 7504 5006 700

8 15011 40015 300

20 00022 80023 200

29 00044 00044 00053 000

7 80011 00016 600

20 00026 00030 000

38 00045 00052 000

60 00068 00085 000

95 00096 500

108 000

150 000

24 00022 000

19 00017 00015 000

12 00010 0009 000

8 5007 5007 000

6 3005 3005 0004 500

13 00011 0009 000

8 5007 5006 700

6 3005 6005 000

4 8004 5004 300

3 8003 6003 400

3 000

30 00028 000

24 00020 00018 000

15 00013 00011 000

10 0009 0008 500

7 5006 3006 0005 300

16 00014 00011 000

10 0009 0008 000

7 5006 7006 000

5 6005 3005 000

4 5004 3004 000

3 600

17 00015 000

13 00012 00010 000

8 5007 5006 300

5 6005 0004 800

4 3003 6003 4003 000

9 5007 5006 300

6 0005 0004 500

4 3003 8003 400

3 2003 0002 800

2 6002 4002 400

2 100

.3937

.4724

.5906

.6693

.7874

.98431.18111.3780

1.57481.77171.9685

2.16542.55912.75593.1496

.7874

.98431.1811

1.37801.57481.7717

1.96852.16542.3622

2.55912.75592.9528

3.14963.34653.5433

3.9370

1.18111.2598

1.37801.57481.8504

2.04722.44092.8346

3.14963.34653.5433

3.93704.72444.92135.5118

2.04722.44092.8346

3.14963.54333.9370

4.33074.72445.1181

5.51185.90556.2992

6.69297.08667.4803

8.4646

1

111

11

11

11

111

11

2

22

2

222

3

.025

.025

.025

.025

.04

.04

.04

.04

.04

.04

.04

.06

.06

.06

.08

.04

.04

.04

.06

.06

.06

.08

.08

.08

.08

.08

.08

.08

.10

.10

.10

.28

.39

.45

.56

.78

.881.271.76

2.252.542.50

3.164.734.735.63

.981.342.00

2.473.133.62

4.505.286.13

7.038.00

10.1

11.311.312.5

18.0

1 1401 520

1 7102 1502 920

3 3904 6805 960

7 3108 1807 890

8 92014 00014 00017 500

3 5704 7706 650

8 1809 940

11 700

13 90016 10018 400

20 70023 40027 900

29 90029 90032 100

40 900

540674

8431 0101 510

1 8302 5603 440

4 5505 1305 220

6 5209 8909 890

11 900

1 7502 4703 730

4 5005 8506 740

8 54010 10011 700

13 50015 30019 100

21 40021 70024 300

33 700


The values have been determined through historical application and practice. For a more complete explanation, see page 274.3) Rating for one million revolutions or 500 hours at 33 RPM.

SFFCMetal Shields

SLLC RemovableMetal Shields

SZZC SyntheticRubber Seals


12/16

MRC Bearing Services

Single-Row Deep Groove

Ball Bearings, S-Type

52

InternalRadialClearance

0.172 25 2.30 0.190.345 50 1.99 0.220.689 100 1.71 0.26

Standard 1.03 150 1.56 0.28(ABMA C0) 1.38 200 0.56 1.45 0.30

2.07 300 1.31 0.343.45 500 1.15 0.385.17 750 1.04 0.426.89 1000 1.00 0.44

0.172 25 1.47 0.380.345 50 1.40 0.400.689 100 1.30 0.43

Loose 1.03 150 1.23 0.46(ABMA C3) 1.38 200 0.44 1.19 0.47

2.07 300 1.12 0.503.45 500 1.02 0.555.17 750 1.00 0.566.89 1000 1.00 0.56

Units UnitsN, mm lb, in X Y

FA FAZD2 FR

> ee

When FA/FR e, use X = 1.0, Y = 0.

Values of Y and e for loads not shown are obtained from chart to the right.

Dynamic and static equivalent radial load andlife rating

Dynamic equivalent radial load

P = XFR + YFA P = Dynamic equivalent radialload

FR = Radial loadFA = Thrust loadZ = Number of ballsD = Ball diameterX = Radial load factorY = Thrust load factore = Limiting factor for FA/FR

Life rating

L10 = (Millions of revolutions)

or

L10h = (Hours)

C = Basic dynamic load ratingP = Dynamic equivalent radial loadn = Speed in RPM

Static equivalent radial loadP0 = 0.6 FR + 0.5 FAP0 is always FRP

0= Static equivalent radial load

FR = Radial loadFA = Thrust load

( )C

P

3

( )CP

1060n

36


13/16

Single Row Deep Groov

Ball Bearings, S-Typ

5

Life (L10) = = = 420.8 106 Rev.

or

Life (L10h) = =

= 3507 Hrs

Life (L10) = = = 684.9 106 Rev.

or

Life (L10h) = =

= 5708 Hrs

Life (L10) = = = 91.0

106

Rev.

or

Life (L10h) = =

= 758 Hrs

Dynamic equivalent radial loadand life calculation examples

Bearing size: 309SSpeed = 2000 RPM

Basic dynamic load rating (C) = 11900 lbf

ZD2 = 3.62

ABMA CO Internal Clearance ABMA C3 Internal Clearance

Case 1

Radial load (FR) = 1890

Equivalent load (P) = X FR + Y FAP = FR = 1890

Case 2


Thrust load (FA) = 1250

Equivalent load (P) = X FR + Y FAFA/ZD2 = 1250/3.62 = 345

X = 0.56

Y = 1.27P = 0.56 1890 + 1.27 1250 = 2646

Case 3



Y = 1.27

P = 1.27 1250 = 1588

Case 3



Y = 1.08

P = 1.08 1250 = 1350

Case 2




X = 0.44

Y = 1.08P = 0.44 1890 + 1.08 1250 = 2182

Case 1


Equivalent load (P) = X FR + YAP = FR = 1890

Life (L10) = = = 249.6 106 Rev.

or

Life (L10h) = =

= 2080 Hrs

Life (L10) = = = 249.6 106 Rev.

or

Life (L10h) = =

= 2080 Hrs

( )CP

3

( )C

P

3

( )CP

3

( )CP

3

( )C

P

3

( )CP

3

( )1190018903

( )CP

10

60n

3

( )CP

3

( )CP

3

( )CP

3

( )CP

3

( )CP

36

1060n

6

10

60n

610

60n

6

1060n

6

10

60n

610

60

2000

6

1060 2000

6

10

60 2000

610

60 2000

6

1060 2000

6

10

60

2000

6

( )1190018903

( )11900

2646

3

( )1190015883

( )1190013503

( )11900

2182

3

( )1190018903

( )1190018903

( )1190026463

( )1190015883

( )1190013503

( )1190021823

( )1190018903

Life (L10) = = = 162.2

106

Rev.

or

Life (L10h) = =

= 1352Hrs


14/16


15/16 5

Hybrid Ceramic Ball Bearing

Prevents Electrical ArcingWhen electrical current passes across bearings, awashboard or fluting pattern appears on the raceways,in addition to a darkened grey appearance. Thisdamage usually results in excessive noise which

requires that the bearing be removed. Besides thesurface damage, premature aging of the lubricant alsooccurs. The natural insulating properties of ceramicmaterial eliminates this type of damage.

Lower Maintenance CostsMaintenance costs can quickly add up if a bearingmust be changed frequently. Anything that extends theservice life of a bearing without increasingmaintenance costs will reduce the operating cost ofthe equipment. Though the initial cost of a hybridbearing is higher than a standard steel bearing, thedifference is quickly recovered in maintenance

savings. Less friction also results in lower energycosts.

Extended Service LifeMost bearings are designed into applications basedon loading conditions and do not take into accountfactors such as lubrication, contamination andmaintenance. Without proper attention to theseexternal factors, a steel bearing rarely reaches itsdesign L10 life and therefore has a shortened servicelife. Because of the properties of ceramics, the servicelife of a hybrid bearing is up to 10 times that of astandard steel bearing. And longer service life reduces

the need for maintenance on your machine as well asthe costly interruptions in production.

Extended Grease LifeIn environments that place high demands on thebearing lubricant, standard bearings experiencesurface wear because of insufficient lubricant film.Bearings can fail if the initial grease charge is notreplenished within an acceptable period of time.Hybrid bearings run cooler and can operate withthinner lubricant films, so there is less aging of thegrease and the required relubrication interval will belonger. The result is increased service life compared to

standard bearings in the same operating conditions.

Lower Operating TemperaturesThe heat generated in bearings is attributable toviscous friction from lubrication and load dependentfriction between the balls and raceways. The source ofthe loading is external as well as internal. There is littlethat can be done to reduce the external loads.However, since ceramic balls have only 40% of thedensity of steel balls, the centrifugal load generated bythe balls is less and the internal friction is lower. Thisprovides cooler running for the same operating

conditions or, if applicable, a higher rotationalspeed while maintaining the same temperature

Reduced Wear from ContaminationIn contaminated environments, solid particlescreate dents in the rolling surfaces and raisededges around those dents. This conditioncauses noise and premature wear as the steelballs roll over those surfaces. The harderceramic ball material smooths the surface

roughness with no material removal. Also, thereis little evidence of adhesive wear as seen insteel bearings. This reduces the noise andwear, which extends the bearing service life.

Reduced Wear from VibrationIn equipment exposed to static vibration, thereis an inherent risk of false brinelling, (thewearing away of the surfaces within the balland raceway contacts) which can eventuallylead to spalling and premature failure. Becausof the lighter weight ceramic balls anddissimilar materials, the risk of false brinelling

damage is much less.

Fluting created by electrical arcing

Wear caused by static vibration


16/16

MRC Bearing ServicesHybrid Ceramic Ball Bearings

Material Properties Bearing Steel Bearing Silicon Nitride Benefit

Mechanical properties

Density [g/cm3] 7.9 3.2 Lower density reduces the centrifugalforce and thereby reduces bearing

friction

Hardness, HV10 [kg/mm2] 700 1600 Higher hardness promotes wear

resistance against hard particles and

lower plastic deformation

Modulus of elasticity, E [GPa] 210 310 Higher modulus of elasticity increases

the bearing stiffness. Hybrid bearings

deflect less under load, providing

more predictable performance

Coefficient of thermal expansion [/C] 12 x 10-6 63 x 10-6 Lower coefficient of expansion

reduces the effects of ring tempera-ture difference resulting in more sta-

ble clearance or preload

Electrical properties

Electrical resistivity [Wm] 0.4 x 10-6 1012 (insulator) The ceramic balls break the electrical

(conductor) current (DC) path and act as an

insulator

Relative dielectric constant N/A 4.2 to 6.1 The ceramic balls break the electrical

current (AC) path and act as a large

impedance

Magnetic field influence Yes No Ceramic balls do not respond to

magnetic forces

Chemical resistance Reactive Inert Ceramic to steel contacts show

no micro-welding and do not seize

during poor lubrication

Documents

Catalog Vong Bi Cau Ranh Sau SKF