20
With Re = 33139 (flow rate = 0.8m/s), since the velocity is 0.5m/s or more and Re
is in the 10000-35000 range, the volumetric flow rate accuracy is ±4% RD.
●
Specifying volumetric flow rate accuracy
(below)
Volumetric flow rate accuracy = 4% RD
Temperature accuracy = 2% RD
Pressure accuracy = 0.01 / fluid pressure (MPa) = 0.01/0.7 = 1.4% DR
Based on these conditions,
At 100m
3
/h (normal), the accuracy is 4.7% RD.
The calculation is similar for 150m
3
/h (normal).
Re = 49517 (velocity = 1.2m/s).
Since Re is more than 35000, the volumetric flow rate accuracy is ±2% RD.
●
Specifying volumetric flow rate accuracy
(below)
Volumetric flow rate accuracy = 2% RD
Temperature accuracy = 2% RD
Pressure accuracy = 0.01 / fluid pressure (MPa) = 0.01/0.7 = 1.4% DR
Based on these conditions,
At 150m
3
/h (normal), the accuracy is 3.2% RD.
●
Specifying volumetric flow rate accuracy
The volumetric flow rate accuracy is specified as follows:
•
MVF50
(pipe size 50A)
· 4% RD when velocity is 0.5m/s or more, and Re is 15000 to less than 35000.
· 2% RD when Re is 35000 or more.
•
MVF80
(pipe size 80A)
· 4% RD when velocity is 0.5m/s or more, and Re is 10000 to less than 35000.
· 2% RD when Re is 35000 or more.
•
MVF100
(pipe size 100A)
· 4% RD when velocity is 0.5m/s or more, and Re is 10000 to less than 40000.
· 2% RD when Re is 40000 or more.
•
MVF150
(pipe size 150A)
· 4% RD when velocity is 0.5m/s or more, and Re is 10000 to less than 50000.
· 2% RD when Re is 50000 or more.
= (2%)
2
+ (2%)
2
+ (1.4%)
2
= 3.2%RD
The accuracy after tem-
perature compensation
The accuracy after tem- = (4%)
2
+ (2%)
2
+ (1.4%)
2
= 4.7%RD
perature compensation
Chapter 5. SPECIFICATIONS
