ASME/ANSI B16.5 Flange Standard Dimension
B16.5 flanges from 1/2″ through 24″ in classes 150, 300, 400, 600, 900, 1500 and 2500
ASME B16.5 standard pdf download
Pipe Flanges and Flanged Fittings: NPS 1/2 through NPS 24 Metric/Inch Standard
B16.5 – 2017
ASME B16.5 Pipe Flanges and Flanged Fittings: NPS 1/2 through NPS 24 Metric/Inch Standard covers pressure-temperature ratings, materials, dimensions, tolerances, marking, testing, and methods of designating openings for pipe flanges and flanged fittings. Included are:
(1) flanges with rating class designations 150, 300, 400, 600, 900, and 1500 in sizes NPS 1/2 through NPS 24 and flanges with rating class designation 2500 in sizes NPS 1/2 through NPS 12, with requirements given in both metric and U.S. Customary units with diameter of bolts and flange bolt holes expressed in inch units;
(2) flanged fittings with rating class designation 150 and 300 in sizes NPS 1/2 through NPS 24, with requirements given in both metric and U.S. Customary units with diameter of bolts and flange bolt holes expressed in inch units;
(3) flanged fittings with rating class designation 400, 600, 900, and 1500 in sizes NPS 1/2 through NPS 24 and flanged fittings with rating class designation 2500 in sizes NPS 1/2 through NPS 12 that are acknowledged in Non-Mandatory Appendix E in which only U.S. Customary units are provided.
B16.5 is limited to flanges and flanged fittings made from cast or forged materials, and blind flanges and certain reducing flanges made from cast, forged, or plate materials. Also included in this Standard are requirements and recommendations regarding flange bolting, flange gaskets, and flange joints.
This Standard is to be used in conjunction with equipment described in other volumes of the ASME B16 Series of Standards as well as with other ASME standards, such as the Boiler and Pressure Vessel Code and the B31 Piping Codes.
Careful application of these B16 Standards will help users to comply with applicable regulations within their jurisdictions, while achieving the operational, cost and safety benefits to be gained from the many industry best-practices detailed within these volumes.
Intended for manufacturers, owners, employers, users and others concerned with the specification, buying, maintenance, training and safe use of valves with pressure equipment, plus all potential governing entities.
FLANGES – DIMENSIONAL TOLERANCES ASME B16.5
DIMENSIONAL TOLERANCES ■ ASME B16.5 | ||||
WELDING NECK FLANGES | ||||
0 | Outside Diameter | When 0 is 24″ or less | ±0.06″ | ±1.6 mm |
When O is over 24” | ±0.12″ | ±3.2 mm | ||
R | Diameter of Contact Face | 0.06” (1.6 mm) raised face | ±0.03″ | ±0.8 mm |
0.25″ (6.4 mm) raised face | ±0.02″ | ±0.5 mm | ||
A | Diameter of Hub at Point of Welding | NPS 5 and smaller | +0.09″, -0.03″ | +2.4 mm, -0.8 mm |
NPS 6 and larger | +0.16″, -0.03″ | +4.0 mm, -0.8 mm | ||
B | Inside Diameter | NPS 10 and smaller | ±0.03″ | ±0.8 mm |
NPS 12 to 18, inclusive | ±0.06″ | ±1.6 mm | ||
NPS 20 and larger | +0.12″, -0.06” | +3.2 mm, -1.6 mm | ||
X | Diameter of Hub at Base | When Hub Base is 24″ or less | ±0.06″ | ±1.6 mm |
When Hub Base is over 24″ | ±0.12″ | ±3.2 mm | ||
c | Thickness | NPS 18 and smaller | +0.12″, -0.00″ | +3.2 mm, -0.0 mm |
NPS 20 and larger | +0.19″, -0.00″ | +4.8 mm, -0.0 mm | ||
Drilling | Bolt Circle Diameter | ±0.06″ | ±1.6 mm | |
Bolt Hole Spacing | ±0.03″ | ±0.8 mm | ||
Eccentricity of Bolt Circle and Facing with Respect to Bore | NPS 21/2 and smaller | ±0.03″ | ±0.8 mm | |
NPS 3 and larger | ±0.06″ | ±1.6 mm | ||
Length Through Hub | NPS 10 and smaller | ±0.06″ | ±1.6 mm | |
NPS 12 and larger | ±0.12″ | ±3.2 mm | ||
SLIP-ON, LAP JOINT, SOCKET WELDING, THREADED and BLIND FLANGES | ||||
O | Outside Diameter | When O is 24″ or less When O is over 24″ |
±0.06″ ±0.12″ | ±1.6 mm ±3.2 mm |
R | Diameter of Contact Face | 0.06″ (1.6 mm) raised face 0.25″ (6.4 mm) raised face | ±0.03″ ±0.02″ | ±0.8 mm ±0.5 mm |
B | Inside Diameter at Face of Socket Welding FlangesInside Diameter of Slip-On, Lap Joint, and Socket Welding | NPS 10 and smaller NPS 12 through 18, inclusive NPS 20 and larger |
±0.03″ ±0.06″ +0.12″, -0.06″ | ±0.8 mm ±1.6 mm +3.2 mm, -1.6 mm |
NPS 10 and smaller NPS 12 and larger |
+0.03″, -0.00″ +0.06″, -0.00″ | +0.8 mm, -0.0 +1.6 mm, -0.0 mm |
||
Q | Counterbore, Threaded Flanges | NPS 10 and smaller NPS 12 and larger |
+0.03″, -0.00″ +0.06″, -0.00″ | +0.8 mm, -0.0 + 1.6 mm, -0.0 mm |
X | Diameter of Hub at Base | NPS 12 and smaller NPS 14 and larger |
+0.09″, -0.06″ ±0.12″ | +2.4 mm, -1.6 ±3.2 mm |
c | Thickness | NPS 18 and smaller NPS 20 and larger |
+0.12″, -0.00″ +0.19″, -0.00″ | +3.2 mm, -0.0 +4.8 mm, -0.0 mm |
Drilling | Bolt Circle Diameter Bolt Hole Spacing | ±0.06″ ±0.03″ | ±1.6 mm ±0.8 mm |
|
Eccentricity of Bolt Circle and Facing with Respect to Bore | NPS 2V2 and smaller NPS 3 and larger |
±0.03″ ±0.06″ | ±0.8 mm ±1.6 mm |
|
Overall Length Through Hub | NPS 18 and smaller NPS 20 and larger |
+0.12”, -0.03” +0.19”, -0.03” |
+3.2 mm, -0.8 mm +4.8 mm, -1.6 mm |