FLANGE DIMENSION TOLERANCES, ASME B16.5 (IN)

WELD NECK FLANGE DIMENSION TOLERANCES, ASME B16.5 (IN)
Weld Neck Flange Dimension
DimensionFlangeTolerance
A Outside Diameter
  • When O.D. is 24" or less: ±1/16" (1.6mm)
  • When O.D. is over 24": ±1/8" (3.2mm)
D Inside Diameter
  • 10" and smaller: ±1/32" (0.8mm)
  • 12" thru 18": +1/8" (3.2mm)
  • 20" and larger: -1/16" (1.6mm)
B Diameter of contact face
  • 1/16" raised face: ±1/32" (0.8mm)
  • 1/4" Raised Face, Tongue & Groove (male & female): ±1/64" (0.4mm)
J Diameter of hub at base
  • When hub base is 24" or smaller: ±1/16" (1.6mm)
  • When hub base is over 24": ±1/8" (3.2mm)
H Diameter of hub at point of welding
  • 5" and smaller: +3/32" (2.4mm), -1/32" (0.8mm)
  • 6" and larger: +5/32" (4.0mm), -1/32 (0.8mm)
P Drilling
  • Bolt circle: ±1/16" (1.6mm)
  • Bolt hole spacing: ±1/32" (0.8mm)
  Eccentricity of bolt circle with respect to facing
  • 2 1/2" and smaller ±1/32" (0.8mm) max.
  • 3" and larger ±1/16" (1.6mm) max.
C Thickness
  • 18" and smaller: ±1/8" (3.2mm), -0"
  • 20" and larger: ±3/16" (4.8mm), -0"
K Length of hub
  • 10" and smaller: ±1/16" (1.6mm)
  • 12" and larger: ±1/8" (3.2mm)

BLIND, LAP JOINT, SLIP-ON, SOCKET, THREADED FLANGE DIMENSION TOLERANCES, ASME B16.5 (IN)
Lap Joint, Blind, Threaded Flanges Dimension
DimensionFlangeTolerance
A Outside Diameter
  • When O.D. is 24" or less: ±1/16" (1.6mm)
  • When O.D. is over 24": ±1/8" (3.2mm)
D Inside Diameter
  • Threaded: within limits of boring gauge
  • Lap Joint, Slip-on, Socket
    • 10" and smaller: ±1/32" (0.8mm), 0"
    • 12" and larger: -1/16" (1.6mm), 0"
B Diameter of contact face
  • 1/16" raised face: ±1/32" (0.8mm)
  • 1/4" Raised Face, Tongue & Groove (male & female): ±1/64" (0.4mm)
E, F, S Diameter of bore
  • Threaded (S): within limits of boring gauge
  • Lap Joint (F), Slip-on (E), Socket (E)
    • 10" and smaller: ±1/32" (0.8mm), 0"
    • 12" and larger: -1/16" (1.6mm), 0"
P Drilling
  • Bolt circle: ±1/16" (1.6mm)
  • Bolt hole spacing: ±1/32" (0.8mm)
  • Eccentricity of bolt circle with respect to facing
    • 2 1/2" and smaller ±1/32" (0.8mm) max.
    • 3" and larger ±1/16" (1.6mm) max.
C Thickness
  • 18" and smaller: ±1/8" (3.2mm), -0"
  • 20" and larger: ±3/16" (4.8mm), -0"
L, M Length of hub
  • 18" and smaller: ±1/8" (3.2mm), ±1/32" (0.8mm)
  • 20" and larger: ±3/16" (4.8mm), ±1/16" (1.6mm)