AS 4087:2004 PN 21

PN21

FLANGE THICKNESS

DRILLING DATA

PN21

NOMINAL 
PIPE SIZE

FLANGE
OUTSIDE
DIAMETER

THICKNESS
OF 
FLANGE

PITCH
CIRCLE
DIAMETER

BOLT
HOLE
DIAMETER

NUMBER
OF
BOLT
HOLES

NOMINAL 
PIPE SIZE

MM

INCH

OD

T

PCD

H

#

MM

INCH

50

2

165

15

127

18

4

50

2

65

2  1/2

185

15

146

18

8

65

2  1/2

80

3

205

15

165

18

8

80

3

100

4

230

19

191

18

8

100

4

150

6

305

24

260

22

12

150

6

200

8

370

24

324

22

12

200

8

225

9

405

30

356

26

12

225

9

250

10

430

30

381

26

12

250

10

300

12

490

30

438

26

16

300

12

350

14

550

30

495

30

16

350

14

375

15

580

38

521

30

16

375

15

400

16

610

38

552

30

20

400

16

450

18

675

38

610

33

20

450

18

500

20

735

48

673

33

24

500

20

600

24

850

58

781

36

24

600

24

700

28

935

58

857

36

24

700

28

750

30

1015

58

940

36

28

750

30

800

32

1060

68

984

36

28

800

32

900

36

1185

68

1105

39

32

900

36

1000

40

1275

78

1194

39

36

1000

40

1200

48

1530

88

1441

42

40

1200

48

Notes:

(1)Flat face and Raised face or "O" ring groove also available.

(2) For special design, pls make an enquiry here.