Oval Smart EX DELTA II Series, Instructions Manual

Page: 10 / 54

D-582-3-E
0
Meter Body
Flow
Direction
Gage Tap
Thermo-
meter Tap
2 to 7D
φ 6
D= Nominal dia.
Fig. 5.
5.2 Pipes to be Used
Pipes having the inside diameter specified at the time you placed an order for this meter should be used
for upstream and downstream pipes. Otherwise, consult the factory for compatibility.
Taps for the pressure gauge and/or thermometer,
if desired, should be located downstream of
the flowmeter as illustrated in Fig. 5. at right.
Thermometer tap should be located on the
downstream side of pressure detection and, at the
same time, upstream of the control valve.
5.3 Location of Pressure Gauge and Thermometer Taps
5.4 Pulsation
Compressors, Roots blowers and other pulsation pressure generating sources could adversely affect
meter performance. Minimize pulsating pressures by referring to the following formula:
N <.2 ρ V
2
(Pa)
where N : Pulsation pressure (Pa)
ρ : Density (kg/m
3
)
V : Minimum velocity (m/s)
If pulsation pressure is excessive, the following measures should be taken into consideration:
① Locate the source of pulsation downstream of the meter or locate it as far from the meter as possible.
② Provide a pulsation attenuator, such as a chamber or pulsation snapper.
③ Shut off valves upstream and downstream of the meter when fluid flow is interrupted (as a precaution
against erratic signal generation at zero flow).
5.5 Prevention of Cavitation (liquid service)
To prevent cavitation, line pressure should be maintained above the level calculated by the following
formula:
P ≧ 2.0 Δ P+.25P
0
(MPa abs.)
where Δ P: Pressure loss (MPa) (See page 8.)
P
0
: Steam pressure of liquid (MPa abs.)
ρ : Density (kg/m
3
)
V : Flow velocity (m/s)