Viega ProPress, Руководство по установке

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Product Information
15 of 38 IM-PP 724607 1218 ProPress
2.5.7 Pressure Surges
■ Pressure surges or transients from fast-acting valves, pump surges,
and other sources that result in water hammer may cause damage to
many system components, including press fittings.
■ When fast-acting valves and/or pumps are incorporated into a system,
the designer and installer should isolate press fittings from sharp
pressure surges.
2.5.8 Rotating a Pressed Fitting
Once a ProPress fitting has been pressed, it can be rotated (not by hand),
but once rotated more than five degrees, the fitting should be repressed
to restore resistance to rotational movement.
If the fitting is re-pressed, care should be taken to align the flat sides on
the jaw with those on the fitting.
2.5.9 Deflection
The pressing process can cause deflection (angular misalignment) to
occur. When pressing Viega ProPress fittings in a system, the deformation
of the fitting is constant. This allows for a consistent leak-free joint every
time and is a result of the pressing technique.
Deflection occurs in the same way for every fitting. The fitting being
pressed will move in the direction of the jaw or ring opening.
■ Since the fitting will deflect toward the opening of the jaw or ring, the
tube end will deflect in the opposite direction.
■ By counteracting the fitting movement, one can minimize the
deflection of the fitting and ultimately the tube.
■ When using strut and clamps, deflection is minimized and nearly
eliminated depending on clamp spacing.
■ ProPress fittings should be isolated or separated by
sufficient distance from pumps, fast-acting valves, and
other sources of pressure transients.
■ The maximum operating pressure in a ProPress system
is 200 psi, which applies to general operation as well as
pressure transients.
■ Good engineering practices should be used to design
the system in a way that minimizes sharp pressure
surges.