marine bearings

Marine grade 316 stainless steel ball bearings for shafts from 3mm to 50mm diameter
See product table below for dimensions and technical drawings

316 grade stainless steel, known as marine grade stainless steel, is an austenitic stainless steel which means it has very good corrosion resistance. Unlike 440 grade martensitic stainless steel, 316 grade is not hardenable by heat treatment. As a result, 316 stainless steel has a much lower load capacity than the standard 440 grade stainless steel most commonly used for bearings. This softer grade of steel is more difficult to grind to very close tolerances than chrome steel or 440 stainless steel so, like plastic bearings, marine grade 316 bearings are semi-precision. 316 stainless steel bearings are slightly magnetic unlike the strongly magnetic 440 grade stainless steel bearings so it is possible to tell the two types apart with a magnet. Corrosion resistant bearings can also be supplied in synthetic materials or zirconia or silicon nitride. For more information on bearings for harsh environments, see our informative guide. Most of our range of marine grade bearings are supplied from stock in the UK.

The 316 grade bearings, shown in the table below, are highly resistant to seawater, salt spray and many aggressive chemicals. The standard range is supplied with polyethylene (PE) cages and seals but alternative cage and seal materials such as PEEK or PTFE can be offered. 316 stainless steel bearings are used in low load and low speed applications in the marine industry when used above the waterline or where the bearings can be washed down after temporary submersion in seawater. They can be immersed in seawater for longer periods if there is a regular flow of water over the bearings as oxygen helps to regenerate the steel. These bearings are found in the food and beverage industry, in bakeries and fish or meat processing plant as well as in the dyeing industry, the textile industry, the pharmaceutical industry and the paper industry.

316 stainless steel has a very wide temperature range. The cage and seals will limit the temperatures at which these bearings can be used but open, full complement 316 grade bearings can withstand temperatures as low as -200°C and as high as 500°C although the load capacity is reduced at more extreme temperatures. Full complement 316 grade bearings and those with PTFE cages and seals are suitable for use in cryogenic applications as PTFE has good low temperature performance down to -190°C. The standard PE cage and seals are not recommended for temperatures below -40°C or above 80°C. If a bearing with a cage and seals is required for high temperature applications, PEEK or PTFE can be used up to 250°C.

Click on INFO in the rows below to display technical drawings of the bearings with load and speed data. Please note that the maximum loads and speeds are used in theoretical life calculations. It is recommended to use bearings at significantly less than the maximum load and speed ratings to ensure reasonable bearing life.

Product Details 5mm to 50mm bore

BORE

(mm)

O.D.

(mm)

WIDTH

(mm)

OPEN BEARING

SEALED BEARING

SMB

REFERENCE

MORE INFO

SMB

REFERENCE

MORE INFO

3

10

4

S316-623

info

S316-623-2PES

info

4

13

5

S316-624

info

S316-624-2PES

info

5

16

5

S316-625

info

S316-625-2PES

info

6

17

6

S316-606

info

S316-606-2PES

info

19

6

S316-626

info

S316-626-2PES

info

7

19

6

S316-607

info

S316-607-2PES

info

22

7

S316-627

info

S316-627-2PES

info

8

22

7

S316-608

info

S316-608-2PES

info

24

8

S316-628

info

S316-628-2PES

info

9

24

7

S316-609

info

S316-609-2PES

info

26

8

S316-629

info

S316-629-2PES

info

10

19

5

S316-6800

info

S316-6800-2PES

info

22

6

S316-6900 info S316-6900-2PES info
26 8

S316-6000

info S316-6000-2PES info

30

9

S316-6200

info

S316-6200-2PES

info

35

11

S316-6300

info

S316-6300-2PES

info

12

21

5

S316-6801

info

S316-6801-2PES

info

24

6 S316-6901 info S316-6901-2PES info

28

8 S316-6001 info S316-6001-2PES info

32

10

S316-6201

info

S316-6201-2PES

info

37

12

S316-6301

info

S316-6301-2PES

info

15

24

5

S316-6802

info

S316-6802-2PES

info

28

7 S316-6902 info S316-6902-2PES info

32

9 S316-6002 info S316-6002-2PES info

35

11

S316-6202

info

S316-6202-2PES

info

42

13

S316-6302

info

S316-6302-2PES

info

17

26

5

S316-6803

info

S316-6803-2PES

info

30

7 S316-6903 info S316-6903-2PES info

35

10 S316-6003 info S316-6003-2PES info

40

12

S316-6203

info

S316-6203-2PES

info

47

14

S316-6303

info

S316-6303-2PES

info

20

32

7

S316-6804

info

S316-6804-2PES

info

37

9 S316-6904 info S316-6904-2PES info

42

12 S316-6004 info S316-6004-2PES info

47

14

S316-6204

info

S316-6204-2PES

info

52

15

S316-6304

info

S316-6304-2PES

info

25

37

7

S316-6805

info

S316-6805-2PES

info

42

9 S316-6905 info S316-6905-2PES info

47

12 S316-6005 info S316-6005-2PES info

52

15

S316-6205

info

S316-6205-2PES

info

62

17

S316-6305

info

S316-6305-2PES

info

30

42

7

S316-6806

info

S316-6806-2PES

info

47

9 S316-6906 info S316-6906-2PES info

55

13 S316-6006 info S316-6006-2PES info

62

16

S316-6206

info

S316-6206-2PES

info

72

19

S316-6306

info

S316-6306-2PES

info

35

47

7

S316-6807

info

S316-6807-2PES

info

55

10 S316-6907 info S316-6907-2PES info

62

14 S316-6007 info S316-6007-2PES info

72

17

S316-6207

info

S316-6207-2PES

info

80

21

S316-6307

info

S316-6307-2PES

info

40

52

7

S316-6808

info

S316-6808-2PES

info

62

12 S316-6908 info S316-6908-2PES info

68

15 S316-6008 info S316-6008-2PES info

80

18

S316-6208

info

S316-6208-2PES

info

90

23

S316-6308

info

S316-6308-2PES

info

45

58

7

S316-6809

info

S316-6809-2PES

info

68

12 S316-6909 info S316-6909-2PES info

75

16 S316-6009 info S316-6009-2PES info

85

19

S316-6209

info

S316-6209-2PES

info

100

25

S316-6309

info

S316-6309-2PES

info

50

65

7

S316-6810

info

S316-6810-2PES

info

72

12 S316-6910 info S316-6910-2PES info
80

16

S316-6010 info S316-6010-2PES info

90

20

S316-6210

info

S316-6210-2PES

info

110

27

S316-6310

info

S316-6310-2PES

info

Our determination to remain specialised gives us a high level of product knowledge, providing bearing and lubrication solutions to existing or potential customers, whether individuals or large corporations. We don’t just sell bearings, we help to solve your problems. - Chris Johnson, managing director of SMB Bearings.