Pocket Guide to Flan..

Large diameter fittings can be stored and protected
with end covers, either plastic or metal. Fittings 1 ~/2 ins.
and smaller should be stored inside, away from the ele-
ments.
Fittings can be stacked in layers with or without dun-
nage. Metal to metal contact will not harm adjacent fit-
tings.
In corrosive areas, spray the fittings with a specified
preservative to prevent rust.
Do not throw or dump the fittings from containers. Per-
manent damage to a fitting's beveled ends may result.
When you are receiving fittings from a vendor or from
another area, always check each and every fitting for
damage and markings per the purchase order specifica-
tions.
Mixed Schedule Fittings
It is very common to have fittings of a mixed schedule
match different pipe wall thicknesses. When the fittings
are machined to a lower pipe schedule, the process is
called "taper boring." Two examples would be:
1. One 12-in. 90-degree weld elbow, schedule 60 long
radius, taper bore each end to extra strong.
2. A 12-in. by 6-in. concentric reducer, schedule 120,
taper bore the 12-in. end to schedule 100, the 6-in.
end to schedule 80.
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