Welding-Neck Flanges
WELDING NECK FLANGES are distinguished from other types by their
long tapered hub and gentle transition of thickness in the region
of the butt weld joining them to the pipe. The long tapered hub
provides an important reinforcement of the flange proper from
the standpoint of strength and resistance to dishing. The smooth
transition from flange thickness to pipe wall thickness effected
by the taper is extremely beneficial under conditions of repeated
bending, caused by line expansion or other variable forces and
produces an endurance strength of welding neck flanged assemblies
equivalent to that of a butt welded joint between pipes, which,
in practice, is the same as that of unwelded pipe. Thus this type
of flange is preferred for every severe service condition, whether
this results from high pressure or from sub-zero or elevated temperature,
and whether loading conditions are substantially constant or fluctuate
between wide limits.
Slip-On Flanges
SLIP-ON FLANGES continue to be preferred to welding neck flanges
by many users on account of their initially lower cost, the reduced
accuracy required in cutting the pipe to length, and the somewhat
greater ease of alignment of the assembly; however their final
installed cost is probably not much, if any, less than that of
welding neck flanges. Their calculated strength under internal
pressure is approximately two-thirds that of welding neck flanges,
and their life under fatigue is about one-third that of the latter.
For these reasons, slip-on flanges are limited to sizes ½"
to 2 ½" in the 1500 lb standard and are not shown in the
2500lb standard.
Orifice Flanges
ORIFICE FLANGES are widely used in conjunction with orifice meters
for measuring the rate of flow of liquids and gases. They are
basically the same as standard welding neck and slip-on flanges
except for the provision of radial, tapped holes in the flange
ring for meter connections and additional bolts to act as jack
screws to facilitate separating the flanges for inspection or
replacement of the orifice plate. In choosing the type of orifice
flange, the considerations affecting the choice of welding neck
and slip-on standard flanges apply with equal force.
Forged Parts and Tooling – A Victim of Supply Chain “Disintegration”
As a new weapon system is created, all participants in the supply
chain are brought together to design and procure components, and
to manufacture the final product.
However, as weapon systems go out of production, the information
flow between the US Department of Defense (DoD) and the Forge
Shop “disintegrates”.
Stainless Steel Flange
Features:
Dimensions:
1) DN: 10-600
2) OD: 1/2 - 24"
3) 150 - 2,500lbs
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