Ultraflux UF 801-P, Руководство пользователя

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NT228B GB2 95 / 98
In this appendix, we provide information on some physical data that you may
need. Many other references are in our didactic handbook or can be obtained
from general data bases, i.e. the Internet.
21.1 Pipes typical dimensions:
The safest investigation is to use pipe manufacture specifications. Then, a short
check on site will confirm the data.
When pipes , as Stainless Steel pipes, PCV pipes, copper pipes, have printed
marks showing their dimensions, read and apply them in the UF 810-P settings.
Note that some pipes use metric units concerning their ID . It is usually
the rule with cast pipes as cast iron (with or without cement liner). So, “Pont-à-
Mousson” (French manufacturer) considers 400 mm I.D. for a 400 mm pipe. From
the circumference and O.D., you will have the whole pipe wall thickness.
It is similar with most of concrete pipes, asbestos pipes, GRP pipes …
ANSI / API pipes consider O.D. dimensions and are labeled in inches. The
thickness and also the I.D. depend on the pipe pressure schedule. So:
 For pipes with diameter 14” and above, the O.D. is obtained by multiplying this
Nominal pipe size by 2.54. A 20” has its O.D. = 508 mm.
 With 10 and 12”, consider 10.75 or 12.75. With 6” and 8”, consider 6” 5/8 and
8” 5/8. A4” has its 4.5”=114.3 mm OD and so one.
21.2 Roughness Coefficient for pipes:
This has some influence on the flow calculation, especially on small
pipes . The problem is that this characteristic is rarely known. We must usually
estimate it. > Please refer to NT 122 manual for typical values.
As a quick guide, we can recommend as typical values:
 Drawn pipes / non ferrous metal, glass, plastics: 0.002 to 0.02 mm if some
deposits.
 Drawn steel & Stainless Steel pipes: 0.02 to 0.06 mm, up to 0.10 if rough
or with deposits.
 Welded Steel pipes : New = 0.05 to 0.1 / Long usage but cleaned = 0.15
to 0.50 / Very old or encrusted or corroded = up to 4.0 mm
 Cast Iron with lining (bitumen, cement, epoxy) = 0.1 to 0.2 / without lining
= 0.2 to 1.0 / encrusted or corroded = up to 3.0 mm.