Environmental Engineering Reference
In-Depth Information
Sleeve support
tube
Male connect
body
Nut
Tu be
Flare
figure 4.14 Flared fitting.
Bite
Ferrule
Pipe thread
Tu be
Body
Nut
figure 4.15 Flareless fitting.
mentioned, any distortion of the smooth, inner wall of a tubing section
causes turbulence in the flow, which lowers the pressure. Figure 4.16
shows three different kinds of incorrect bends and one correct bend.
From the figure, it should be apparent how the incorrect bends constrict
the flow, causing turbulence and lower pressure.
4.10.5 Types of Tubing
Common types of metal tubing in industrial service include:
•
Copper
is seamless, fully annealed, and furnished in coils or in
straight lengths. In water treatment applications, copper tubing has
replaced lead and galvanized iron in service line installations
because it is flexible, easy to install, corrosion
resistant in most soils, and able to withstand
high pressure. It is not sufficiently soluble in
most water to be a health hazard, but corro-
sive water may dissolve enough copper to
cause green stains on plumbing fixtures.
Copper water service tubing is usually connected by either flare or
compression fittings. Copper plumbing is usually connected with
solder joints (AWWA, 1996).
Key Point:
Annealing
is the process of
reheating a metal and then letting it
cool slowly. In the production of tubing,
annealing is performed to make the tub-
ing softer and less brittle.
•
aluminum
is seamless, annealed, and suitable for bending and
flaring.
•
Steel
is seamless and fully annealed and is also available as a
welded type, suitable for bending and flaring.
