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5 inch class 150 flange: dimensions, bolt circle and drilling (ASME B16.5)

The 5 inch class 150 flange to ASME B16.5 is 10 in (254 mm) across, with 8 holes of 0.88 in (22.2 mm) on a 8.5 in (215.9 mm) bolt circle, for 3/4 in bolts; the pipe is 5.56 in (141.3 mm) outside. The holes straddle the centre lines, the first one 22.5° off, and the chord between neighbouring holes, which is the divider setting for stepping the drilling out, is 3.25 in (82.6 mm).

The 5 inch class 150 flange as the calculator draws it: the outline, the bore at the pipe outside diameter and the 8 holes.

Dimensions

Outside diameter10 in (254 mm)
Bolt circle (PCD)8.5 in (215.9 mm)
Number of holes8
Hole diameter0.88 in (22.2 mm)
Bolts3/4 in
Pipe outside diameter5.56 in (141.3 mm)
Angle between holes45°
First hole from the centre line22.5°
Chord between neighbouring holes3.25 in (82.6 mm)

Draw this flange: 1:1 template and DXF

Hole coordinates

From the centre of the flange, in mm, with the first hole 22.5° off the horizontal axis and the others counter-clockwise, as the standards lay the drilling out.

Hole Angle x (mm) y (mm)
1 22.5° 99.7 41.3
2 67.5° 41.3 99.7
3 112.5° -41.3 99.7
4 157.5° -99.7 41.3
5 202.5° -99.7 -41.3
6 247.5° -41.3 -99.7
7 292.5° 41.3 -99.7
8 337.5° 99.7 -41.3

Questions

How many bolts does a %{size} %{class} flange have?
%{holes}, of %{bolt}, through holes of %{hole} on a %{circle} bolt circle.
What is the bolt circle of a %{size} %{class} flange?
%{circle}. The holes are %{angle}° apart, and the first one sits %{half}° off the centre line, so that two flanges mate in any symmetric position. The chord between neighbouring holes is %{chord}.
Can a %{size} %{class} flange be cut from plate?
As a plate flange, for low pressure: ducts, tanks, water lines. The outline and the drilling above are what the flange calculator draws, with the 1:1 template and the DXF for plasma or laser. A pressure flange to %{standard} is forged, with a hub and a raised face, and its thickness and facing come from the standard.