ABB TRIO-WIRL SR4000, Инструкция по эксплуатации

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Vortex Meter (TRIO-WIRL V) 3 - 14 PN25080
TRIO-WIRL INSTRUCTION MANUAL
3.5.2 Liquid.
3.5.2.1 Static Pressure, Liquid
To prevent cavitation when metering liquids a positive
static pressure (back pressure) is required. Its value
can be estimated using the following equation:
p
2
≥ (
1.3 x p
Vapor
) + (2.6 x
∆ρ
’)
Where:
p
2
=Positive downstream static pressure [psi]
p
Vapor
=Fluid vapor pressure at operating temp. [psi]
∆ρ
’ =Fluid pressure drop [psi] (See Figure 3-15 )
3.5.2.2 Pressure Drop, Liquids
See Figure below for water (70ºF, 14.67 psia,
ρ
- 8.34
lb/gal). For other fluid densities (
ρ
) the pressure drop
can be calculated using the following equation:
Where:
∆
p’ = Pressure drop, fluid [psi]
∆
p = Pressure drop, water (Refer to Figure 3-15 )
ρ
= Operating Density lb/gal
EXAMPLE FOR LIQUIDS
Determine the flowmeter size for metering 14,000 gph
of a liquid with a density of 7.10 lb/gal and a kinematic
viscosity of 2 cSt.
1. Find Q
V
= maximum
Q
VMAX
= 17,400 gph for 2 in. meter (from Table 3-5 )
2. Using 2” meter size with viscosity of 2 cSt
Q
VMIN
= 1,800 gph (Refer to Table 3-6 )
3. Calculate Pressure drop (Q
V
= 14,000 gph) at
ρ
= 7.10 lb/gal
TABLE 3-5. VORTEX FLOW RANGES, WATER
Meter Size
Flow Range
GPH
Frequency
at Q
V
max
[Hz]
Inch DN Qvmin Qvmax
1/2 15 130 1450 450
1 25 420 4700 400
1-1/2 40 660 12670 280
2 50 800 17400 180
3 80 2650 42300 130
4 100 3100 57000 80
6 150 8700 140000 55
8 200 18500 247000 43
10 250 21600 382000 28
12 300 35600 540000 23
p
'
∆
ρ
8.34
---------- p ∆ ×
=
p
'
∆
7.10
8.34
---------- 9 ×
7.6
psi
= =
TABLE 3-6. MINIMUM & MAXIMUM FLOWRATES VS. VISCOSITY, LIQUID
Q
vmin
[gph]
Qvmax
[gph]
Frequency
@ Q
V
max [Hz]
Centistokes < 1 2 3 4 5 6 7
Meter Size
Inch DN
1/2 15
130
250 350 450 550 650 750 1450 450
1 25
420
850 1300 1800 2100 2600 3000 4700 400
1-1/2 40
660
1400 2000 2700 3200 3900 4400 12670 280
2 50
800
1800 2400 3200 4000 4800 5600 17400 180
3 80
2650
5000 7000 9400 12000 15000 18000 42300 130
4 100
3100
6100 9200 14000 18000 21000 25000 57000 80
6 150
8700
18000 28000 38000 48000 58000 69000 140000 55
8 200
18500
33000 47000 60000 70000 81000 93000 247000 43
10 250
21600
39000 58000 78000 100000 130000 150000 382000 28
12 300
35600
65000 90000 120000 160000 180000 190000 540000 23
Conditions @ 70
o
F, 14.67 psig & ρ =8.34 lb/gal