1/2" NB (DN15) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole
Diameter
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 80 55 4 M10 11 38 40 2 12 (1) 12
PN 10 95 65 4 M12 14 46 45 2 14 (1) 16 14
PN 16 95 65 4 M12 14 46 45 2 14 (1) 6 (2) 16 14
PN 25 95 65 4 M12 14 46 45 2 16 (1) 8 (2) 16 14
PN 40 95 65 4 M12 14 46 45 2 9 (2) 16 16
PN 64 105 75 4 M12 14 45 2 20
ANSI
Class 125/150 3 1/2" (89) 2 3/8" (60) 4 1/2" (13) 5/8" (16) 1 3/8" (35) 1/16" (2) 5/16" (8) 7/16" (11)
Class 300 3 3/4" (95) 2 5/8" (67) 4 1/2" (13) 5/8" (16) 1 3/8" (35) 1/16" (2) 1/2" (13) 1/2" (13)
Class 600 3 3/4" (95) 2 5/8" (67) 4 1/2" (13) 5/8" (16) 1 3/8" (35) 1/4" (6) 9/16" (14)
Class 900 4 3/4" (121) 3 1/4" (83) 4 3/4" (19) 7/8" (22) 1 3/8" (35) 1/4" (6) 7/8" (22)
Class 1500 4 3/4" (121) 3 1/4" (83) 4 3/4" (19) 7/8" (22) 1 3/8" (35) 1/4" (6) 7/8" (22)
BS 10
Table A 3 3/4" (95) 2 5/8" (67) 4 1/2" (13) 9/16" (14) 1/2" (13) 1/4" (6)
Table D 3 3/4" (95) 2 5/8" (67) 4 1/2" (13) 9/16" (14) 1/2" (13) 1/4" (6) 3/8" (10)
Table E 3 3/4" (95) 2 5/8" (67) 4 1/2" (13) 9/16" (14) 1/2" (13) 1/4" (6) 3/8" (10)
Table F 3 3/4" (95) 2 5/8" (67) 4 1/2" (13) 9/16" (14) 1/2" (13) 5/16" (8) 3/8" (10)
Table H 4 1/2" (114) 3 1/4" (83) 4 5/8" (16) 11/16" (17) 2 1/4" (57) 1/16" (2) 5/8" (16) 3/8" (10) 1/2" (13)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

3/4" NB (DN20) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole
Diameter
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 90 65 4 M10 11 48 50 2 14 (1) 14
PN 10 105 75 4 M12 14 56 58 2 16 (1) 18 16
PN 16 105 75 4 M12 14 56 58 2 16 (1) 6 (2) 18 16
PN 25 105 75 4 M12 14 56 58 2 18 (1) 8 (2) 18 16
PN 40 105 75 4 M12 14 56 58 2 9 (2) 18 18
PN 64 130 90 4 M16 18 58 2 22
PN 100 130 90 4 M16 18 58 2 22
ANSI
Class 125/150 3 7/8" (98) 2 3/4" (70) 4 1/2" (13) 5/8" (16) 1 11/16" (43) 1/16" (2) 11/32" (9) 9/16" (14)
Class 300 4 5/8" (117) 3 1/4" (83) 4 5/8" (16) 3/4" (19) 1 11/16" (43) 1/16" (2) 17/32" (13) 5/8" (16)
Class 600 4 5/8" (117) 3 1/4" (83) 4 5/8" (16) 3/4" (19) 1 11/16" (43) 1/4" (6) 5/8" (16)
Class 900 5 1/8" (130) 3 1/2" (89) 4 3/4" (19) 7/8" (22) 1 11/16" (43) 1/4" (6) 1" (25)
Class 1500 5 1/8" (130) 3 1/2" (89) 4 3/4" (19) 7/8" (22) 1 11/16" (43) 1/4" (6) 1" (25)
BS 10
Table A 4" (102) 2 7/8" (73) 4 1/2" (13) 9/16" (14) 1/2" (13) 1/4" (6)
Table D 4" (102) 2 7/8" (73) 4 1/2" (13) 9/16" (14) 1/2" (13) 1/4" (6) 3/8" (10)
Table E 4" (102) 2 7/8" (73) 4 1/2" (13) 9/16" (14) 1/2" (13) 1/4" (6) 3/8" (10)
Table F 4" (102) 2 7/8" (73) 4 1/2" (13) 9/16" (14) 1/2" (13) 5/16" (8) 3/8" (10)
Table H 4 1/2" (114) 3 1/4" (83) 4 5/8" (16) 11/16" (17) 2 1/4" (57) 1/16" (2) 5/8" (16) 3/8" (10) 1/2" (13)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

1" NB (DN25) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole
Diameter
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 100 75 4 M10 11 58 60 3 2 14 (1) 14
PN 10 115 85 4 M12 14 65 68 3 2 16 (1) 18 16
PN 16 115 85 4 M12 14 65 68 3 2 16 (1) 8 (2) 18 16
PN 25 115 85 4 M12 14 65 68 3 2 18 (1) 9 (2) 18 16
PN 40 115 85 4 M12 14 65 68 3 2 11 (2) 18 18
PN 64 140 100 4 M16 18 68 2 24
PN 100 140 100 4 M16 18 68 2 24
ANSI
Class 125/150 4 1/4" (108) 3 1/8" (79) 4 1/2" (13) 5/8" (16) 2" (51) 1/16" (2) 7/16" (11) 3/8" (10) 7/16" (11) 9/16" (14)
Class 300 4 7/8" (124) 3 1/2" (89) 4 5/8" (16) 3/4" (19) 2" (51) 1/16" (2) 19/32" (15) 11/16" (17)
Class 600 4 7/8" (124) 3 1/2" (89) 4 5/8" (16) 3/4" (19) 2" (51) 1/4" (6) 11/16" (17)
Class 900 5 7/8" (149) 4" (102) 4 7/8" (22) 1" (25) 2" (51) 1/4" (6) 1 1/8" (29)
Class 1500 5 7/8" (149) 4" (102) 4 7/8" (22) 1" (25) 2" (51) 1/4" (6) 1 1/8" (29)
BS 10
Table A 4 1/2" (114) 3 1/4" (83) 4 1/2" (13) 9/16" (14) 1/2" (13) 5/16" (8)
Table D 4 1/2" (114) 3 1/4" (83) 4 1/2" (13) 9/16" (14) 1/2" (13) 5/16" (8) 3/8" (10)
Table E 4 1/2" (114) 3 1/4" (83) 4 1/2" (13) 9/16" (14) 1/2" (13) 5/16" (8) 3/8" (10)
Table F 4 3/4" (121) 3 7/16" (87) 4 5/8" (16) 11/16" (17) 1/2" (13) 3/8" (10) 3/8" (10)
Table H 4 3/4" (121) 3 7/16" (87) 4 5/8" (16) 11/16" (17) 2 1/2" (64) 1/16" (2) 3/4" (19) 7/16" (11) 9/16" (14)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

1 1/4" NB (DN32) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 120 90 4 M12 14 14 69 70 3 2 16 (1) 14
PN 10 140 100 4 M16 19 18 76 78 3 2 18 (1) 18 18
PN 16 140 100 4 M16 19 18 76 78 3 2 18 (1) 8 (2) 18 18
PN 25 140 100 4 M16 19 18 76 78 3 2 20 (1) 9 (2) 18 18
PN 40 140 100 4 M16 19 18 76 78 3 2 11 (2) 18 20
PN 64 155 110 4 M20 22 78 2 26
PN 100 155 110 4 M20 22 78 2 26
ANSI
Class 125/150 4 5/8" (117) 3 1/2" (89) 4 1/2" (13) 5/8" (16) 5/8" (16) 2 1/2" (64) 1/16" (2) 1/2" (13) 13/32" (10) 1/2" (13) 5/8" (16)
Class 300 5 1/4" (133) 3 7/8" (98) 4 5/8" (16) 3/4" (19) 2 1/2" (64) 1/16" (2) 5/8" (16) 3/4" (19)
Class 600 5 1/4" (133) 3 7/8" (98) 4 5/8" (16) 3/4" (19) 2 1/2" (64) 1/4" (6) 13/16" (21)
Class 900 6 1/4" (159) 4 3/8" (111) 4 7/8" (22) 1" (25) 2 1/2" (64) 1/4" (6) 1 1/8" (29)
Class 1500 6 1/4" (159) 4 3/8" (111) 4 7/8" (22) 1" (25) 2 1/2" (64) 1/4" (6) 1 1/8" (29)
BS 10
Table A 4 3/4" (121) 3 7/16" (87) 4 1/2" (13) 9/16" (14) 9/16" (14) 5/8" (16) 5/16" (8)
Table D 4 3/4" (121) 3 7/16" (87) 4 1/2" (13) 9/16" (14) 9/16" (14) 5/8" (16) 5/16" (8) 1/2" (13)
Table E 4 3/4" (121) 3 7/16" (87) 4 1/2" (13) 9/16" (14) 9/16" (14) 5/8" (16) 5/16" (8) 1/2" (13)
Table F 5 1/4" (133) 3 7/8" (98) 4 5/8" (16) 11/16" (17) 11/16" (17) 5/8" (16) 3/8" (10) 1/2" (13)
Table H 5 1/4" (133) 3 7/8" (98) 4 5/8" (16) 11/16" (17) 11/16" (17) 3" (76) 1/16" (2) 7/8" (22) 7/16" (11) 11/16" (17)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

1 1/2" NB (DN40) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 130 100 4 M12 14 14 78 80 3 2 16 (1) 14
PN 10 150 110 4 M16 19 18 84 88 3 2 18 (1) 18 19
PN 16 150 110 4 M16 19 18 84 88 3 2 18 (1) 9 (2) 18 19
PN 25 150 110 4 M16 19 18 84 88 3 2 20 (1) 11 (2) 18 19
PN 40 150 110 4 M16 19 18 84 88 3 2 13 (2) 18 19
PN 64 170 125 4 M20 22 88 2 28
PN 100 170 125 4 M20 22 88 2 28
ANSI
Class 125/150 5" (127) 3 7/8" (98) 4 1/2" (13) 5/8" (16) 5/8" (16) 2 7/8" (73) 1/16" (2) 9/16" (14) 7/16" (11) 9/16" (14) 11/16" (17)
Class 300 6 1/8" (156) 4 1/2" (114) 4 3/4" (19) 7/8" (22) 2 7/8" (73) 1/16" (2) 11/16" (17) 13/16" (21)
Class 600 6 1/8" (156) 4 1/2" (114) 4 3/4" (19) 7/8" (22) 2 7/8" (73) 1/4" (6) 7/8" (22)
Class 900 7" (178) 4 7/8" (124) 4 1" (25) 1 1/8" (29) 2 7/8" (73) 1/4" (6) 1 1/4" (32)
Class 1500 7" (178) 4 7/8" (124) 4 1" (25) 1 1/8" (29) 2 7/8" (73) 1/4" (6) 1 1/4" (32)
BS 10
Table A 5 1/4" (133) 3 7/8" (98) 4 1/2" (13) 9/16" (14) 9/16" (14) 5/8" (16) 3/8" (10)
Table D 5 1/4" (133) 3 7/8" (98) 4 1/2" (13) 9/16" (14) 9/16" (14) 5/8" (16) 3/8" (10) 1/2" (13)
Table E 5 1/4" (133) 3 7/8" (98) 4 1/2" (13) 9/16" (14) 9/16" (14) 5/8" (16) 3/8" (10) 1/2" (13)
Table F 5 1/2" (140) 4 1/8" (105) 4 5/8" (16) 11/16" (17) 11/16" (17) 5/8" (16) 7/16" (11) 1/2" (13)
Table H 5 1/2" (140) 4 1/8" (105) 4 5/8" (16) 11/16" (17) 11/16" (17) 3 1/4" (83) 1/16" (2) 7/8" (22) 1/2" (13) 11/16" (17)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

2" NB (DN50) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 140 110 4 M12 14 14 88 90 3 2 16 (1) 14
PN 10 165 125 4 M16 19 18 99 102 3 2 20 (1) 18 19
PN 16 165 125 4 M16 19 18 99 102 3 2 20 (1) 11 (2) 18 19
PN 25 165 125 4 M16 19 18 99 102 3 2 22 (1) 11 (2) 20 19
PN 40 165 125 4 M16 19 18 99 102 3 2 13 (2) 20 19
PN 64 180 135 4 M20 22 102 2 26
PN 100 195 145 4 M24 26 102 2 30
ANSI
Class 125/150 6" (152) 4 3/4" (121) 4 5/8" (16) 3/4" (19) 3/4" (19) 3 5/8" (92) 1/16" (2) 5/8" (16) 1/2" (13) 5/8" (16)
Class 300 6 1/2" (165) 5" (127) 8 5/8" (16) 3/4" (19) 3 5/8" (92) 1/16" (2) 3/4" (19) 7/8" (22)
Class 600 6 1/2" (165) 5" (127) 8 5/8" (16) 3/4" (19) 3 5/8" (92) 1/4" (6) 1" (25)
Class 900 8 1/2" (216) 6 1/2" (165) 8 7/8" (22) 1" (25) 3 5/8" (92) 1/4" (6) 1 1/2" (38)
Class 1500 8 1/2" (216) 6 1/2" (165) 8 7/8" (22) 1" (25) 3 5/8" (92) 1/4" (6) 1 1/2" (38)
BS 10
Table A 6" (152) 4 1/2" (114) 4 5/8" (16) 11/16" (17) 11/16" (17) 5/8" (16) 3/8" (10)
Table D 6" (152) 4 1/2" (114) 4 5/8" (16) 11/16" (17) 11/16" (17) 11/16" (17) 3/8" (10) 9/16" (14)
Table E 6" (152) 4 1/2" (114) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 3/8" (10) 9/16" (14)
Table F 6 1/2" (165) 5" (127) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 7/16" (11) 5/8" (16)
Table H 6 1/2" (165) 5" (127) 4 5/8" (16) 11/16" (17) 11/16" (17) 4" (102) 1/16" (2) 1" (25) 1/2" (13) 3/4" (19)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

2 1/2" NB (DN65) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 160 130 4 M12 14 14 108 110 2 3 16 (1) 14
PN 10 185 145 4 (4) M16 19 18 118 122 2 3 20 (1) 18 19
PN 16 185 145 4 (4) M16 19 18 118 122 2 3 20 (1) 13 (2) 18 19
PN 25 185 145 8 M16 19 18 118 122 2 3 24 (1) 13 (2) 22 19
PN 40 185 145 8 M16 19 18 118 122 2 3 14 (2) 22 19
PN 64 205 160 8 M20 22 122 2 26
PN 100 220 170 8 M24 26 122 2 34
ANSI
Class 125/150 7" (178) 5 1/2" (140) 4 5/8" (16) 3/4" (19) 3/4" (19) 4 1/8" (105) 1/16" (2) 11/16" (17) 9/16" (14) 11/16" (17)
Class 300 7 1/2" (191) 5 7/8" (149) 8 3/4" (19) 7/8" (22) 4 1/8" (105) 1/16" (2) 13/16" (21) 1" (25)
Class 600 7 1/2" (191) 5 7/8" (149) 8 3/4" (19) 7/8" (22) 4 1/8" (105) 1/4" (6) 1 1/8" (29)
Class 900 9 5/8" (244) 7 1/2" (191) 8 1" (25) 1 1/8" (29) 4 1/8" (105) 1/4" (6) 1 5/8" (41)
Class 1500 9 5/8" (244) 7 1/2" (191) 8 1" (25) 1 1/8" (29) 4 1/8" (105) 1/4" (6) 1 5/8" (41)
BS 10
Table A 6 1/2" (165) 5" (127) 4 5/8" (16) 11/16" (17) 11/16" (17) 11/16" (17) 7/16" (11)
Table D 6 1/2" (165) 5" (127) 4 5/8" (16) 11/16" (17) 11/16" (17) 11/16" (17) 7/16" (11) 9/16" (14)
Table E 6 1/2" (165) 5" (127) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 7/16" (11) 9/16" (14)
Table F 7 1/4" (184) 5 3/4" (146) 8 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 1/2" (13) 5/8" (16)
Table H 7 1/4" (184) 5 3/4" (146) 8 5/8" (16) 11/16" (17) 11/16" (17) 4 1/2" (114) 1/16" (2) 1" (25) 9/16" (14) 3/4" (19)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced. (4) Steel flanges in this DN and PN may be supplied with 8 holes. For compliance with these, equivalent cast iron flanges may be supplied with 8 holes as special order and after agreement between manufacturer and customer.

3" NB (DN80) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 190 150 4 M16 19 18 124 128 3 2 18 (1) 16
PN 10 200 160 8 M16 19 18 132 138 3 2 22 (1) 20 19
PN 16 200 160 8 M16 19 18 132 138 3 2 22 (1) 13 (2) 20 19
PN 25 200 160 8 M16 19 18 132 138 3 2 26 (1) 14 (2) 24 19
PN 40 200 160 8 M16 19 18 132 138 3 2 16 (2) 24 19
PN 64 215 170 8 M20 22 138 2 28
PN 100 230 180 8 M24 26 138 2 36
ANSI
Class 125/150 7 1/2" (191) 6" (152) 4 5/8" (16) 3/4" (19) 3/4" (19) 5" (127) 1/16" (2) 3/4" (19) 5/8" (16) 3/4" (19)
Class 300 8 1/4" (210) 6 5/8" (168) 8 3/4" (19) 7/8" (22) 5" (127) 1/16" (2) 29/32" (23) 1 1/8" (29)
Class 600 8 1/4" (210) 6 5/8" (168) 8 3/4" (19) 7/8" (22) 5" (127) 1/4" (6) 1 1/4" (32)
Class 900 9 1/2" (241) 7 1/2" (192) 8 7/8" (22) 1" (25) 5" (127) 1/4" (6) 1 1/2" (38)
Class 1500 10 1/2" (267) 8" (203) 8 1 1/8" (29) 1 1/4" (32) 5" (127) 1/4" (6) 1 7/8" (48)
BS 10
Table A 7 1/4" (184) 5 3/4" (146) 4 5/8" (16) 11/16" (17) 11/16" (17) 11/16" (17) 1/2" (13)
Table D 7 1/4" (184) 5 3/4" (146) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 1/2" (13) 9/16" (14)
Table E 7 1/4" (184) 5 3/4" (146) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 1/2" (13) 9/16" (14)
Table F 8" (203) 6 1/2" (165) 8 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 9/16" (14) 5/8" (16)
Table H 8" (203) 6 1/2" (165) 8 5/8" (16) 11/16" (17) 11/16" (17) 5" (127) 1/16" (2) 1 1/8" (29) 5/8" (16) 7/8" (22)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

4" NB (DN100) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 210 170 4 M16 19 18 144 148 3 2 18 (1) 16
PN 10 220 180 8 M16 19 18 156 158 3 2 24 (1) 20 19
PN 16 220 180 8 M16 19 18 156 158 3 2 24 (1) 16 (2) 20 19
PN 25 235 190 8 M20 23 22 156 162 3 2 28 (1) 17 (2) 24 19
PN 40 235 190 8 M20 23 22 156 162 3 2 19 (2) 24 19
PN 64 250 200 8 M24 26 162 2 30
PN 100 265 210 8 M27 30 162 2 40
ANSI
Class 125/150 9" (229) 7 1/2" (191) 8 5/8" (16) 3/4" (19) 3/4" (19) 6 3/16" (157) 1/16" (2) 15/16" (24) 11/16" (17) 15/16" (24)
Class 300 10" (254) 7 7/8" (200) 8 3/4" (19) 7/8" (22) 6 3/16" (157) 1/16" (2) 1 1/16" (27) 1 1/4" (32)
Class 600 10 3/4" (273) 8 1/2" (216) 8 7/8" (22) 1" (25) 6 3/16" (157) 1/4" (6) 1 1/2" (38)
Class 900 11 1/2" (292) 9 1/4" (235) 8 1 1/8" (29) 1 1/4" (32) 6 3/16" (157) 1/4" (6) 1 3/4" (44)
Class 1500 12 1/4" (311) 9 1/2" (241) 8 1 1/4" (32) 1 3/8" (35) 6 3/16" (157) 1/4" (6) 2 1/8" (54)
BS 10
Table A 8 1/2" (216) 7" (178) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 5/8" (16)
Table D 8 1/2" (216) 7" (178) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 5/8" (16) 11/16" (17)
Table E 8 1/2" (216) 7" (178) 8 5/8" (16) 11/16" (17) 11/16" (17) 7/8" (22) 5/8" (16) 11/16" (17)
Table F 9" (229) 7 1/2" (191) 8 5/8" (16) 11/16" (17) 11/16" (17) 7/8" (22) 11/16" (17) 3/4" (19)
Table H 9" (229) 7 1/2" (191) 8 5/8" (16) 11/16" (17) 11/16" (17) 6" (152) 1/16" (2) 1 1/4" (32) 3/4" (19) 1" (25)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Flange thicknesses for copper alloy are from BS4504. (3) Copper alloy flanges are always flat-faced.

5" NB (DN125) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (2)
Raised Face
Diameter
Steel (2)
Raised Face
Height
Cast Iron (2)
Raised Face
Height
Steel (2)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 240 200 8 M16 19 18 174 178 3 2 20 (1) 18
PN 10 250 210 8 M16 19 18 184 188 3 2 26 (1) 22 19
PN 16 250 210 8 M16 19 18 184 188 3 2 26 (1) 22 19
PN 25 270 220 8 M24 28 26 184 188 3 2 30 (1) 26 19
PN 40 270 220 8 M24 28 26 184 188 3 2 26 23.5
PN 64 295 240 8 M27 30 188 2 34
PN 100 315 250 8 M30 33 188 2 40
ANSI
Class 125/150 10" (254) 8 1/2" (216) 8 3/4" (19) 7/8" (22) 7/8" (22) 7 5/16" (186) 1/16" (2) 15/16" (24) 3/4" (19) 15/16" (24)
Class 300 11" (279) 9 1/4" (235) 8 3/4" (19) 7/8" (22) 7 5/16" (186) 1/16" (2) 1 1/8" (29) 1 3/8" (35)
Class 600 13" (330) 10 1/2" (267) 8 1" (25) 1 1/8" (29) 7 5/16" (186) 1/4" (6) 1 3/4" (44)
Class 900 13 3/4" (349) 11" (279) 8 1 1/4" (32) 1 3/8" (35) 7 5/16" (186) 1/4" (6) 2" (51)
Class 1500 14 3/4" (375) 11 1/2" (292) 8 1 1/2" (38) 1 5/8" (41) 7 5/16" (186) 1/4" (6) 2 7/8" (73)
BS 10
Table A 10" (254) 8 1/4" (210) 4 5/8" (16) 11/16" (17) 11/16" (17) 3/4" (19) 11/16" (17)
Table D 10" (254) 8 1/4" (210) 8 5/8" (16) 11/16" (17) 11/16" (17) 13/16" (21) 11/16" (17) 11/16" (17)
Table E 10" (254) 8 1/4" (210) 8 5/8" (16) 11/16" (17) 11/16" (17) 7/8" (22) 11/16" (17) 11/16" (17)
Table F 11" (279) 9 1/4" (235) 8 3/4" (19) 7/8" (22) 7/8" (22) 1" (25) 3/4" (19) 7/8" (22)
Table H 11" (279) 9 1/4" (235) 8 3/4" (19) 7/8" (22) 7/8" (22) 7" (178) 1/16" (2) 1 3/8" (35) 7/8" (22) 1 1/8" (29)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Copper alloy flanges are always flat-faced.

6" NB (DN150) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (2)
Raised Face
Diameter
Steel (2)
Raised Face
Height
Cast Iron (2)
Raised Face
Height
Steel (2)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 265 225 8 M16 19 18 199 202 3 2 20 (1) 18
PN 10 285 240 8 M20 23 22 211 212 3 2 26 (1) 22 19
PN 16 285 240 8 M20 23 22 211 212 3 2 26 (1) 22 19
PN 25 300 250 8 M24 28 26 211 218 3 2 34 (1) 28 20
PN 40 300 250 8 M24 28 26 211 218 3 2 28 26
PN 64 345 280 8 M30 33 218 2 36
PN 100 355 290 12 M30 33 218 2 44
ANSI
Class 125/150 11" (279) 9 1/2" (241) 8 3/4" (19) 7/8" (22) 7/8" (22) 8 1/2" (216) 1/16" (2) 1" (25) 13/16" (21) 1" (25)
Class 300 12 1/2" (318) 10 5/8" (270) 12 3/4" (19) 7/8" (22) 8 1/2" (216) 1/16" (2) 1 3/16" (30) 1 7/16" (37)
Class 600 14" (356) 11 1/2" (292) 12 1" (25) 1 1/8" (29) 8 1/2" (216) 1/4" (6) 1 7/8" (48)
Class 900 15" (381) 12 1/2" (318) 12 1 1/8" (29) 1 1/4" (32) 8 1/2" (216) 1/4" (6) 2 3/16" (56)
Class 1500 15 1/2" (394) 12 1/2" (318) 12 1 3/8" (35) 1 1/2" (38) 8 1/2" (216) 1/4" (6) 3 1/4" (83)
BS 10
Table A 11" (279) 9 1/4" (235) 4 5/8" (16) 11/16" (17) 11/16" (17) 13/16" (21) 11/16" (17)
Table D 11" (279) 9 1/4" (235) 8 5/8" (16) 11/16" (17) 11/16" (17) 13/16" (21) 11/16" (17) 11/16" (17)
Table E 11" (279) 9 1/4" (235) 8 3/4" (19) 7/8" (22) 7/8" (22) 7/8" (22) 11/16" (17) 11/16" (17)
Table F 12" (305) 10 1/4" (260) 12 3/4" (19) 7/8" (22) 7/8" (22) 1" (25) 7/8" (22) 7/8" (22)
Table H 12" (305) 10 1/4" (260) 12 3/4" (19) 7/8" (22) 7/8" (22) 8 1/4" (210) 1/16" (2) 1 3/8" (35) 1" (25) 1 1/8" (29)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Copper alloy flanges are always flat-faced.

8" NB (DN200) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (2)
Raised Face
Diameter
Steel (2)
Raised Face
Height
Cast Iron (2)
Raised Face
Height
Steel (2)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 320 280 8 M16 19 18 254 258 3 2 22 (1) 20
PN 10 340 295 8 M20 23 22 266 268 3 2 26 (1) 24 20
PN 16 340 295 12 M20 23 22 266 268 3 2 30 (1) 24 20
PN 25 360 310 12 M24 28 26 274 278 3 2 34 (1) 30 22
PN 40 375 320 12 M27 31 30 284 285 3 2 34 30
PN 64 415 345 12 M33 36 285 2 42
PN 100 430 360 12 M33 36 285 2 52
ANSI
Class 125/150 13 1/2" (343) 11 3/4" (298) 8 3/4" (19) 7/8" (22) 7/8" (22) 10 5/8" (270) 1/16" (2) 1 1/8" (29) 15/16" (24) 1 1/8" (29)
Class 300 15" (381) 13" (330) 12 7/8" (22) 1" (25) 10 5/8" (270) 1/16" (2) 1 3/8" (35) 1 5/8" (41)
Class 600 16 1/2" (419) 13 3/4" (349) 12 1 1/8" (29) 1 1/4" (32) 10 5/8" (270) 1/4" (6) 2 3/16" (56)
Class 900 18 1/2" (470) 15 1/2" (394) 12 1 3/8" (35) 1 1/2" (38) 10 5/8" (270) 1/4" (6) 2 1/2" (64)
Class 1500 19" (483) 15 1/2" (394) 12 1 5/8" (41) 1 3/4" (44) 10 5/8" (270) 1/4" (6) 3 5/8" (92)
BS 10
Table A 13 1/4" (337) 11 1/2" (292) 8 5/8" (16) 11/16" (17) 11/16" (17) 7/8" (22) 3/4" (19) 1/2" (13)
Table D 13 1/4" (337) 11 1/2" (292) 8 5/8" (16) 11/16" (17) 11/16" (17) 7/8" (22) 3/4" (19) 3/4" (19)
Table E 13 1/4" (337) 11 1/2" (292) 8 3/4" (19) 7/8" (22) 7/8" (22) 1" (25) 3/4" (19) 3/4" (19)
Table F 14 1/2" (368) 12 3/4" (324) 12 3/4" (19) 7/8" (22) 7/8" (22) 1 1/8" (29) 1" (25) 1" (25)
Table H 14 1/2" (368) 12 3/4" (324) 12 3/4" (19) 7/8" (22) 7/8" (22) 10 1/4" (260) 1/16" (2) 1 1/2" (38) 1 1/4" (32) 1 1/4" (32)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Copper alloy flanges are always flat-faced.

10" NB (DN250) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 375 335 12 M16 19 18 309 312 3 2 24 (1) 22
PN 10 395 (2) 350 12 M20 23 22 319 320 3 2 28 (1) 26 22
PN 16 405 (2) 355 12 M24 28 26 319 320 3 2 32 (1) 26 22
PN 25 425 370 12 M27 31 30 330 335 3 2 32 24.5
PN 40 450 385 12 M30 34 33 345 345 3 2 38 34.5
PN 64 470 400 12 M33 36 345 2 46
PN 100 505 430 12 M36 39 345 2 60
ANSI
Class 125/150 16" (406) 14 1/4" (362) 12 7/8" (22) 1" (25) 1" (25) 12 3/4" (324) 1/16" (2) 1 3/16" (30) 1" (25) 1 3/16" (30)
Class 300 17 1/2" (445) 15 1/4" (387) 16 1" (25) 1 1/8" (29) 12 3/4" (324) 1/16" (2) 1 7/8" (41)
Class 600 20" (508) 17" (432) 16 1 1/4" (32) 1 3/8" (35) 12 3/4" (324) 1/4" (6) 2 1/2" (64)
Class 900 21 1/2" (546) 18 1/2" (470) 16 1 3/8" (35) 1 1/2" (38) 12 3/4" (324) 1/4" (6) 2 3/4" (70)
Class 1500 23" (584) 19" (483) 12 1 7/8" (41) 2" (51) 12 3/4" (324) 1/4" (6) 4 1/4" (108)
BS 10
Table A 16" (406) 14" (356) 8 3/4" (19) 7/8" (22) 7/8" (22) 15/16" (24) 3/4" (19)
Table D 16" (406) 14" (356) 8 3/4" (19) 7/8" (22) 7/8" (22) 1" (25) 3/4" (19) 3/4" (19)
Table E 16" (406) 14" (356) 12 3/4" (19) 7/8" (22) 7/8" (22) 1" (25) 7/8" (22) 7/8" (22)
Table F 17" (432) 15" (381) 12 7/8" (22) 1" (25) 1" (25) 1 1/8" (29) 1" (25) 1" (25)
Table H 17" (432) 15" (381) 12 7/8" (22) 1" (25) 1" (25) 12 1/4" (311) 1/16" (2) 1 5/8" (41) 1 3/8" (35) 1 3/8" (35)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) For ductile iron pipes and fittings the outside diameters shall be 400mm for PN10 & PN16. (3) Copper alloy flanges are always flat-faced.

12" NB (DN300) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 440 395 12 M20 23 22 363 365 4 2 24 (1) 22
PN 10 445 (2) 400 12 M20 23 22 370 370 4 2 28 (1) 26 24.5
PN 16 460 (2) 410 12 M24 28 26 370 378 4 2 32 (1) 28 24.5
PN 25 485 430 16 M27 31 30 389 395 4 2 40 (1) 34 27.5
PN 40 515 450 16 M30 34 33 409 410 4 2 42 39.5
PN 64 530 460 16 M33 36 410 2 52
PN 100 585 500 16 M39 42 410 2 68
ANSI
Class 125/150 19" (483) 17" (432) 12 7/8" (22) 1" (25) 1" (25) 15" (381) 1/16" (2) 1 1/4" (32) 1 1/16" (27) 1 1/4" (32)
Class 300 20 1/2" (521) 17 3/4" (451) 16 1 1/8" (29) 1 1/4" (32) 15" (381) 1/16" (2) 2" (51)
Class 600 22" (559) 19 1/4" (489) 20 1 1/4" (32) 1 3/8" (35) 15" (381) 1/4" (6) 2 5/8" (67)
Class 900 24" (610) 21" (533) 20 1 3/8" (35) 1 1/2" (38) 15" (381) 1/4" (6) 3 1/8" (80)
Class 1500 26 1/2" (673) 22 1/2" (571) 16 2" (51) 2 1/8" (54) 15" (381) 1/4" (6) 4 7/8" (124)
BS 10
Table A 18" (457) 16" (406) 8 3/4" (19) 7/8" (22) 7/8" (22) 15/16" (24) 7/8" (22)
Table D 18" (457) 16" (406) 12 3/4" (19) 7/8" (22) 7/8" (22) 1" (25) 7/8" (22) 7/8" (22)
Table E 18" (457) 16" (406) 12 7/8" (22) 1" (25) 1" (25) 1 1/8" (29) 1" (25) 1" (25)
Table F 19 1/4" (489) 17 1/4" (438) 16 7/8" (22) 1" (25) 1" (25) 1 1/4" (32) 1 1/8" (29) 1 1/8" (29)
Table H 19 1/4" (489) 17 1/4" (438) 16 7/8" (22) 1" (25) 1" (25) 14 1/4" (362) 1/16" (2) 1 3/4" (44) 1 1/2" (38) 1 1/2" (38)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) For ductile iron pipes and fittings the outside diameters shall be 455mm for PN10 & PN16. (3) Copper alloy flanges are always flat-faced.

14" NB (DN350) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (2)
Raised Face
Diameter
Steel (2)
Raised Face
Height
Cast Iron (2)
Raised Face
Height
Steel (2)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 490 445 12 M20 23 22 413 415 4 2 26 (1) 22
PN 10 505 460 16 M20 23 22 429 430 4 2 30 (1) 26 24.5
PN 16 520 470 16 M24 28 26 429 438 4 2 36 (1) 30 26.5
PN 25 555 490 16 M30 34 33 448 450 4 2 44 (1) 38 30
PN 40 580 510 16 M33 37 36 465 465 4 2 46 44
PN 64 600 525 16 M36 39 465 2 56
PN 100 655 560 16 M45 48 465 2 74
ANSI
Class 125/150 21" (533) 18 3/4" (476) 12 1" (25) 1 1/8" (29) 1 1/8" (29) 16 1/4" (413) 1/16" (2) 1 3/8" (35) 1 3/8" (35)
Class 300 23" (584) 20 1/4" (514) 20 1 1/8" (29) 1 1/4" (32) 16 1/4" (413) 1/16" (2) 2 1/8" (54)
Class 600 23 3/4" (603) 20 3/4" (527) 20 1 3/8" (35) 1 1/2" (38) 16 1/4" (413) 1/4" (6) 2 3/4" (70)
Class 900 25 1/4" (641) 22" (559) 20 1 1/2" (38) 1 5/8" (41) 16 1/4" (413) 1/4" (6) 3 3/8" (86)
Class 1500 29 1/2" (749) 25" (635) 16 2 1/4" (57) 2 3/8" (60) 16 1/4" (413) 1/4" (6) 5 1/4" (133)
BS 10
Table A 20 3/4" (527) 18 1/2" (470) 8 7/8" (22) 1" (25) 1" (25) 1" (25) 1" (25)
Table D 20 3/4" (527) 18 1/2" (470) 12 7/8" (22) 1" (25) 1" (25) 1 1/8" (29) 1" (25) 1" (25)
Table E 20 3/4" (527) 18 1/2" (470) 12 7/8" (22) 1" (25) 1" (25) 1 1/4" (32) 1" (25) 1" (25)
Table F 21 3/4" (552) 19 1/2" (495) 16 1" (25) 1 1/8" (29) 1 1/8" (29) 1 3/8" (35) 1 1/4" (32) 1 1/4" (32)
Table H 21 3/4" (552) 19 1/2" (495) 16 1" (25) 1 1/8" (29) 1 1/8" (29) 16 1/2" (419) 1/16" (2) 1 7/8" (48) 1 5/8" (41) 1 5/8" (41)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Copper alloy flanges are always flat-faced.

16" NB (DN400) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (2)
Raised Face
Diameter
Steel (2)
Raised Face
Height
Cast Iron (2)
Raised Face
Height
Steel (2)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 540 495 16 M20 23 22 463 465 4 2 28 (1) 22
PN 10 565 515 16 M24 28 26 480 482 4 2 32 (1) 26 24.5
PN 16 580 525 16 M27 31 30 480 490 4 2 38 (1) 32 28
PN 25 620 550 16 M33 37 36 503 505 4 2 48 (1) 40 32
PN 40 660 585 16 M36 41 39 535 535 4 2 50 48
PN 64 670 585 16 M39 42 535 2 60
PN 100 715 620 16 M45 48 535 2 78
ANSI
Class 125/150 23 1/2" (597) 21 1/4" (540) 16 1" (25) 1 1/8" (29) 1 1/8" (29) 18 1/2" (470) 1/16" (2) 1 7/16" (37) 1 7/16" (37)
Class 300 25 1/2" (648) 22 1/2" (572) 20 1 1/4" (32) 1 3/8" (35) 18 1/2" (470) 1/16" (2) 2 1/4" (57)
Class 600 27" (686) 23 3/4" (603) 20 1 1/2" (38) 1 5/8" (41) 18 1/2" (470) 1/4" (6) 3" (76)
Class 900 27 3/4" (705) 24 1/4" (616) 20 1 5/8" (41) 1 3/4" (44) 18 1/2" (470) 1/4" (6) 3 1/2" (89)
Class 1500 32 1/2" (826) 27 3/4" (705) 16 2 1/2" (64) 2 5/8" (67) 18 1/2" (470) 1/4" (6) 5 3/4" (146)
BS 10
Table A 22 3/4" (578) 20 1/2" (521) 12 7/8" (22) 1" (25) 1" (25) 1 1/16" (27) 1" (25)
Table D 22 3/4" (578) 20 1/2" (521) 12 7/8" (22) 1" (25) 1" (25) 1 1/8" (29) 1" (25) 1" (25)
Table E 22 3/4" (578) 20 1/2" (521) 12 7/8" (22) 1" (25) 1" (25) 1 1/4" (32) 1" (25) 1" (25)
Table F 24" (610) 21 3/4" (552) 20 1" (25) 1 1/8" (29) 1 1/8" (29) 1 3/8" (35) 1 1/4" (32) 1 1/4" (32)
Table H 24" (610) 21 3/4" (552) 20 1" (25) 1 1/8" (29) 1 1/8" (29) 19" (483) 1/16" (2) 2" (51) 1 3/4" (44) 1 3/4" (44)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Copper alloy flanges are always flat-faced.

18" NB (DN450) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (2)
Raised Face
Diameter
Steel (2)
Raised Face
Height
Cast Iron (2)
Raised Face
Height
Steel (2)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 595 550 16 M20 23 22 518 520 4 2 28 (1) 22
PN 10 615 565 20 M24 28 26 530 532 4 2 32 (1) 28 25.5
PN 16 640 585 20 M27 31 30 548 550 4 2 40 (1) 40 30
PN 25 670 600 20 M33 37 36 548 555 4 2 50 (1) 46 34.5
PN 40 685 610 20 M36 41 39 560 560 4 2 57 49
PN 64
PN 100
ANSI
Class 125/150 25" (635) 22 3/4" (578) 16 1 1/8" (29) 1 1/4" (32) 1 1/4" (32) 21" (533) 1/16" (2) 1 9/16" (40) 1 9/16" (40)
Class 300 28" (711) 24 3/4" (629) 24 1 1/4" (32) 1 3/8" (35) 21" (533) 1/16" (2) 2 3/8" (60)
Class 600 29 1/4" (743) 25 3/4" (654) 20 1 5/8" (41) 1 3/4" (44) 21" (533) 1/4" (6) 3 1/4" (83)
Class 900 31" (787) 27" (686) 20 1 7/8" (48) 2" (51) 21" (533) 1/4" (6) 4" (102)
Class 1500 36" (914) 30 1/2" (775) 16 2 3/4" (70) 2 7/8" (73) 21" (533) 1/4" (6) 6 3/8" (162)
BS 10
Table A 25 1/4" (641) 23" (584) 12 7/8" (22) 1" (25) 1 1/16" (27) 1 1/16" (27)
Table D 25 1/4" (641) 23" (584) 12 7/8" (22) 1" (25) 1 1/4" (32) 1 1/8" (29) 1 1/8" (29)
Table E 25 1/4" (641) 23" (584) 16 7/8" (22) 1" (25) 1 3/8" (35) 1 1/8" (29) 1 1/8" (29)
Table F 26 1/2" (673) 24" (610) 20 1 1/8" (29) 1 1/4" (32) 1 1/2" (38) 1 3/8" (35) 1 3/8" (35)
Table H 26 1/2" (673) 24" (610) 20 1 1/8" (29) 1 1/4" (32) 21" (533) 1/16" (2) 2 1/8" (54) 1 7/8" (48) 1 7/8" (48)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Copper alloy flanges are always flat-faced.

20" NB (DN500) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (3)
Raised Face
Diameter
Steel (3)
Raised Face
Height
Cast Iron (3)
Raised Face
Height
Steel (3)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 645 600 20 M20 23 22 568 570 4 2 30 (1) 24 (2)
PN 10 670 620 20 M24 28 26 582 585 4 2 34 (1) 28 (2) 26.5
PN 16 715 650 20 M30 34 33 609 610 4 2 42 (1) 44 (2) 31.5
PN 25 730 660 20 M33 37 36 609 615 4 2 52 (1) 48 (2) 36.5
PN 40 755 670 20 M39 44 42 615 615 4 2 57 (2) 52
PN 64 800 705 20 M45 48 615 2 68 (2)
PN 100 870 760 20 M52 56 615 2 94 (2)
ANSI
Class 125/150 27 1/2" (699) 25" (635) 20 1 1/8" (29) 1 1/4" (32) 1 1/4" (32) 23" (584) 1/16" (2) 1 11/16" (43) 1 11/16" (43)
Class 300 30 1/2" (775) 27" (686) 24 1 1/4" (32) 1 3/8" (35) 23" (584) 1/16" (2) 2 1/2" (64)
Class 600 32" (813) 28 1/2" (724) 24 1 5/8" (41) 1 3/4" (44) 23" (584) 1/4" (6) 3 1/2" (89)
Class 900 33 3/4" (857) 29 1/2" (749) 20 2" (51) 2 1/8" (54) 23" (584) 1/4" (6) 4 1/4" (108)
Class 1500 38 3/4" (984) 32 3/4" (832) 16 3" (76) 3 1/8" (79) 23" (584) 1/4" (6) 7" (178)
BS 10
Table A 27 3/4" (705) 25 1/4" (641) 12 7/8" (22) 1" (25) 1" (25) 1 1/8" (29) 1 1/8" (29)
Table D 27 3/4" (705) 25 1/4" (641) 16 7/8" (22) 1" (25) 1" (25) 1 1/4" (32) 1 1/4" (32)
Table E 27 3/4" (705) 25 1/4" (641) 16 7/8" (22) 1" (25) 1" (25) 1 1/2" (38) 1 1/4" (32) 1 1/4" (32)
Table F 29" (737) 26 1/2" (673) 24 1 1/8" (29) 1 1/4" (32) 1 1/4" (32) 1 5/8" (41) 1 1/2" (38) 1 1/2" (38)
Table H 29" (737) 26 1/2" (673) 24 1 1/8" (29) 1 1/4" (32) 1 1/4" (32) 23 1/2" (597) 1/16" (2) 2 1/4" (57) 2" (51) 2" (51)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) These flange thicknesses are changed substantially as a result of the flange calculation method used in BS EN 1092-1. (3) Copper alloy flanges are always flat-faced.

24" NB (DN600) Flange Dimensions

Standard / Rating Flange
Diameter
Bolt Circle
Diameter
Number
of Bolts
Bolt
Diameter
Hole Diameter
Iron
Hole Diameter
Steel
Raised Face
Diameter
Cast Iron (2)
Raised Face
Diameter
Steel (2)
Raised Face
Height
Cast Iron (2)
Raised Face
Height
Steel (2)
Flange Thickness
Grey
Cast Iron
Copper
Alloy
Cast &
Forged Steel
Ductile
Cast Iron
BS EN 1092
PN 6 755 705 20 M24 28 26 667 670 5 2 30 (1) 30
PN 10 780 725 20 M27 31 30 682 685 5 2 36 (1) 34 30
PN 16 840 770 20 M33 37 36 720 725 5 2 48 (1) 54 36
PN 25 845 770 20 M36 41 39 720 720 5 2 58 42
PN 40 890 795 20 M45 50 48 735 735 5 2 72 58
PN 64 930 820 20 M52 56 735 2 76
ANSI
Class 125/150 32" (813) 29 1/2" (749) 20 1 1/4" (32) 1 3/8" (35) 1 3/8" (35) 27 1/4" (692) 1/16" (2) 1 7/8" (48) 1 7/8" (48)
Class 300 36" (914) 32" (813) 24 1 1/2" (38) 1 5/8" (41) 27 1/4" (692) 1/16" (2) 2 3/4" (70)
Class 600 37" (940) 33" (838) 24 1 7/8" (48) 2" (51) 27 1/4" (692) 1/4" (6) 4" (102)
Class 900 41" (1041) 35 1/2" (902) 20 2 1/2" (64) 2 5/8" (67) 27 1/4" (692) 1/4" (6) 5 1/2" (140)
Class 1500 46" (1168) 39" (991) 16 3 1/2" (89) 3 5/8" (92) 27 1/4" (692) 1/4" (6) 8" (203)
BS 10
Table A 32 1/2" (826) 29 3/4" (756) 12 1" (25) 1 1/8" (29) 1 1/8" (29) 1 3/16" (30) 1 3/16" (30)
Table D 32 1/2" (826) 29 3/4" (756) 16 1" (25) 1 1/8" (29) 1 1/8" (29) 1 3/8" (35) 1 3/8" (35) 1 3/8" (35)
Table E 32 1/2" (826) 29 3/4" (756) 16 1 1/8" (29) 1 1/4" (32) 1 1/4" (32) 1 5/8" (41) 1 1/2" (38) 1 1/2" (38)
Table F 33 1/2" (851) 30 3/4" (781) 24 1 1/4" (32) 1 1/4" (32) 1 3/8" (35) 1 3/4" (44) 1 5/8" (41) 1 5/8" (41)
Table H 33 1/2" (851) 30 3/4" (781) 24 1 1/4" (32) 1 3/8" (35) 1 3/8" (35) 27 1/2" (699) 1/16" (2) 2 1/2" (64) 2 1/4" (57) 2 1/4" (57)

Metric dimensions are given in millimetres. Imperial dimensions are followed by their approximate metric equivalent in brackets. (1) These flange thicknesses are also valid for ductile iron flanges type 21-2. (2) Copper alloy flanges are always flat-faced.

Shopping Basket
Download your document for free today!
Please supply your email below and we will send over the selected download to you shortly.

    Email