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Flange Studs Size Chart

Flange Studs Size Chart

ASME B16.5-2013. Length of studs are measured 1st full thread to last full thread.

Class 150 LB

Nominal Pipe Size

Diameter of Studs

No. of Studs

Bolt Length of Studs

Ring Joint Gasket No.

Raised Face

Ring Joint

1/2

1/2

4

2-1/4

3/4

1/2

4

2-1/2

1

1/2

4

2-1/2

3

R15

1-1/4

1/2

4

2-3/4

3-1/4

R17

1-1/2

1/2

4

2-3/4

3-1/4

R19

2

5/8

4

3-1/4

3-1/4

R22

2-1/2

5/8

4

3-1/2

4

R25

3

5/8

4

3-1/2

4-1/4

R29

3-1/2

5/8

8

3-1/2

4-1/4

R33

4

5/8

8

3-1/2

4-1/4

R36

5

3/4

8

3-3/4

4-1/2

R40

6

3/4

8

4

4-1/2

R43

8

3/4

8

4-1/4

4-3/4

R48

10

7/8

12

4-3/4

5-1/4

R52

12

7/8

12

4-3/4

5-1/2

R56

14

1

12

5-1/4

6

R59

16

1

16

5-1/2

6

R64

18

1-1/8

16

6

6-1/2

R68

20

1-1/8

20

6-1/4

7

R72

22

1-1/4

20

6-1/2

7-1/4

R80

24

1-1/4

20

7

7-3/4

R76

Class 300 LB

Nominal Pipe Size

Diameter of Studs

No. of Studs

Bolt Length of Studs

Ring Joint Gasket No.

Raised Face

Ring Joint

1/2

1/2

4

2-1/2

3

R11

3/4

5/8

4

3

3-1/4

R13

1

5/8

4

3-1/4

3-1/4

R16

1-1/4

5/8

4

3-1/4

3-1/4

R18

1-1/2

3/4

4

3-1/2

4

R20

2

5/8

8

3-1/2

4-1/4

R23

2-1/2

3/4

8

4

4-1/2

R26

3

3/4

8

4-1/4

5

R31

3-1/2

3/4

8

4-1/4

5

R34

4

3/4

8

4-1/2

5-1/4

R37

5

3/4

8

4-3/4

5-1/4

R41

6

3/4

12

4-3/4

5-3/4

R45

8

7/8

12

5-1/2

6-1/4

R49

10

1

16

6-1/4

7-1/4

R53

12

1-1/8

16

6-3/4

7-1/2

R57

14

1-1/8

20

7

7-3/4

R61

16

1-1/4

20

7-1/2

8-1/4

R65

18

1-1/4

24

7-3/4

8-1/2

R69

20

1-1/4

24

8-1/4

9-1/4

R73

22

1-1/2

24

8-3/4

9-3/4

R81

24

1-1/2

24

9-1/4

10-1/4

R77

Class 400 LB

Nominal Pipe Size

Diameter of Studs

No. of Studs

Bolt Length of Studs

Ring Joint Gasket No.

Raised Face

Ring Joint

1/2

1/2

4

3

3

R11

3/4

5/8

4

3-1/2

3-1/2

R13

1

5/8

4

3-1/2

3-1/2

R16

1-1/4

5/8

4

3-3/4

3-3/4

R18

1-1/2

3/4

4

4-1/4

4-1/4

R20

2

5/8

8

4-1/4

4-1/4

R23

2-1/2

3/4

8

4-3/4

4-3/4

R26

3

3/4

8

5

5

R31

3-1/2

7/8

8

5-1/2

5-1/2

R34

4

7/8

8

5-1/2

5-1/2

R37

5

7/8

8

5-3/4

5-3/4

R41

6

7/8

12

6

6

R45

8

1

12

6-3/4

6-3/4

R49

10

1-1/8

16

7-1/2

7-1/2

R53

12

1-1/4

16

8

8

R57

14

1-1/4

20

8-1/4

8-1/4

R61

16

1-3/8

20

8-3/4

8-3/4

R65

18

1-3/8

24

9

9

R69

20

1-1/2

24

9-1/2

9-1/2

R73

22

1-5/8

24

10

10-1/2

R81

24

1-3/4

24

10-1/2

11

R77

Class 600 LB

Nominal Pipe Size

Diameter of Studs

No. of Studs

Bolt Length of Studs

Ring Joint Gasket No.

Raised Face

Ring Joint

1/2

1/2

4

3

3

R11

3/4

5/8

4

3-1/4

3-1/4

R13

1

5/8

4

3-1/2

3-1/2

R16

1-1/4

5/8

4

3-3/4

3-3/4

R18

1-1/2

3/4

4

4-1/4

4-1/4

R20

2

5/8

8

4-1/4

4-1/2

R23

2-1/2

3/4

8

5

5-1/4

R26

3

3/4

8

5

5-1/4

R31

3-1/2

7/8

8

5-1/2

5-1/2

R34

4

7/8

8

5-3/4

6

R37

5

1

8

6-1/2

6-1/2

R41

6

1

12

6-3/4

7

R45

8

1-1/8

12

7-3/4

8

R49

10

1-1/4

16

8-1/2

8-3/4

R53

12

1-1/4

20

8-3/4

9

R57

14

1-3/8

20

9-1/4

9-1/2

R61

16

1-1/2

20

10

10-1/4

R65

18

1-5/8

20

10-3/4

11

R69

20

1-5/8

24

11-1/2

11-3/4

R73

22

1-3/4

24

12

12-1/2

R81

24

1-7/8

24

13

13-1/2

R77

Flange Studs Size Chart

ASME B16.5-2013. Length of studs are measured 1st full thread to last full thread.

Class 900 LB

Nominal Pipe Size

Diameter of Studs

No. of Studs

Bolt Length of Studs

Ring Joint Gasket No.

Raised Face

Ring Joint

1/2

3/4

4

4

4-1/4

R12

3/4

3/4

4

4-1/4

4-1/2

R14

1

7/8

4

4-3/4

5

R16

1-1/4

7/8

4

5

5

R18

1-1/2

1

4

5-1/4

5-1/2

R20

2

7/8

8

5-1/2

5-3/4

R24

2-1/2

1

8

6-1/4

6-1/4

R27

3

7/8

8

5-1/2

5-3/4

R31

4

1-1/8

8

6-1/2

6-3/4

R37

5

1-1/4

8

7-1/2

7-1/2

R41

6

1-1/8

12

7-1/2

7-3/4

R45

8

1-3/8

12

8-1/2

8-3/4

R49

10

1-3/8

16

9

9-1/4

R53

12

1-3/8

20

9-3/4

10

R57

14

1-1/2

20

10-1/2

11

R62

16

1-5/8

20

11

11-1/2

R66

18

1-7/8

20

12-3/4

13-1/4

R70

20

2

20

13-1/2

14-1/4

R74

24

2-1/2

20

17

18

R78

Class 1500 LB

Nominal Pipe Size

Diameter of Studs

No. of Studs

Bolt Length of Studs

Ring Joint Gasket No.

Raised Face

Ring Joint

1/2

3/4

4

4

4-1/4

R12

3/4

3/4

4

4-1/4

4-1/2

R14

1

7/8

4

4-3/4

5

R16

1-1/4

7/8

4

5

5

R18

1-1/2

1

4

5-1/4

5-1/2

R20

2

7/8

8

5-1/2

5-3/4

R24

2-1/2

1

8

6-1/4

6-1/4

R27

3

1-1/8

8

6-3/4

7

R35

4

1-1/4

8

7-1/2

7-3/4

R39

5

1-1/2

8

9-3/4

9-3/4

R44

6

1-3/8

12

10

10-1/2

R46

8

1-5/8

12

11-1/4

11-3/4

R50

10

1-7/8

12

13-1/4

13-1/2

R54

12

2

16

14-3/4

15-1/4

R58

14

2-1/4

16

16

16-3/4

R63

16

2-1/2

16

17-1/2

18-1/2

R67

18

2-3/4

16

19-1/4

20-1/4

R71

20

3

16

21

22-1/4

R75

24

3-1/2

16

24

25-1/2

R79

Class 2500 LB

Nominal Pipe Size

Diameter of Studs

No. of Studs

Bolt Length of Studs

Ring Joint Gasket No.

Raised Face

Ring Joint

1/2

3/4

4

4-3/4

4-3/4

R13

3/4

3/4

4

4-3/4

5

R16

1

7/8

4

5-1/4

5-1/2

R18

1-1/4

1

4

6

6

R21

1-1/2

1-1/8

4

6-1/2

6-3/4

R23

2

1

8

6-3/4

7

R26

2-1/2

1-1/8

8

7-3/4

8

R28

3

1-1/4

8

8-1/2

9

R32

4

1-1/2

8

9-3/4

10-1/4

R38

5

1-3/4

8

11-3/4

12-1/4

R42

6

2

8

13-1/2

14

R47

8

2

12

15

15-1/2

R51

10

2-1/2

12

19

20

R55

12

2-3/4

12

21

22

R60

Chapter 1: Forces Acting on the Bolted Flange Connection