Flanged water meters / flow meters, DN40-400-
IP65/68
-CE – Operating Manual
Page 12 of 19
7.7 Prevent overstressing of the water meter due to the attached piping or other
equipment. If necessary,
install the water meter on a pedestal or a bracket. The upstream and downstream piping must be properly
fastened so that no component of the system shifts by the action of water when the water meter is removed
or detached on one of its ends.
7.8 The operating pressure at the inlet of
the water meter’s measurement chamber must be ≤ the maximum
allowed pressure (MAP) for which the water meter is rated. The minimum allowed pressure (MAP) at the
water meter’s outlet must be 30 kPa (0.3 bar).
7.9 The installation of the water meter in the system must conform to the intended operating orientation
(horizontal or vertical, as applicable by specification) (see Table 2).
7.10 The MWN
(WPH-01) Nubis
and JS
Impero
water meters can be installed without straight piping
sections upstream (U0) and downstream (D0).
7.10.1 Special installation requirements for the water meters
The piping can feature straight sections upstream and downstream for protection against the negative effects
of water flow turbulence due to bends, valves, and other system components, the upstream side can use a
straight piping section with a length of L=3DN (the DN of the water meter).
If the water meter is to be installed downstream of a double bend, a check valve, a pump, or any other
component which generates significant flow turbulence, double the specified upstream straight piping section
length as follows: 2L;
if the turbulence-generating component is a piston pump, triple the length: 3L. To avoid
an upstream straight section this long, a flow vane can be installed upstream
of the water meter. The
turbulence forming downstream of the water meter is generally inconsequential to reading accuracy.
However,
if backflows occur then there is a risk of failure of the propeller/vane wheel bearings. It is
recommended to counter this by installing (if feasible) a short straight section
downstream of the water
meter, and the section length must be: L
1
= 2DN.
CAUTION! Never
attempt to weld a system
in which a water
meter is installed, as it this may cause a failure!
7.11 The upstream and
downstream pipe sections must be concentric to one another.
Install all seals concentric to the pipe bore
centreline. It is not permitted to install the water meter offset
(eccentrically) from the pipe centreline, and especially to have the piping-to-water meter
seals offset and
obstructing the pipeline bore, as this may cause a flow
turbulence.
7.12 The water flow through the water
meter must be in the direction shown by the flow arrow affixed to both
sides of
the water meter body.
7.13 The water meters are intended for connection by flanged ends. The flanges are fabricated as per
PN-
ISO-7005-2 and PN10 in the standard version. Other fabrication reference standards are available on
request. The system pipe connections with the water meter must have flanges with the same bolt hole
pattern as the water meter flanges.
7.14 The water meters must be secured to the pipes with bolts and washers in a size compatible with the
flange bolt holes.
8. Irrigation flow meter installation requirements
8.1 The installation location should provide easy access for the processes of installation, removal, servicing
and easy reading, as well as protecting the irrigation flow meter from sub-zero temperatures.
