Yoshitake CT-1, Product Manual, Page: 3 / 20

-2-
■
EPDT-318a
■
2. Nominal size selection
The appropriate nominal size can be calculated by obtaining the Cv value for the
operating conditions in question, as shown below.
【
In case of steam application
】
P
1
：
Inlet press.(MPa
･
A) W
：
Max. steam flow rate(kg/h)
P
2
：
Reduced press.(MPa
･
A) Δ P
：Ｐ
1
－Ｐ
2
(MPa)
k
：
1+0.0013×
｛
Super-heated temp. (
℃
)
－
Saturated heat temp. (
℃
)
｝
Cv
：
Cv value depend on each size
【
In case of air application
】
P
1
：
Inlet press.(MPa
･
A) Q
：
Max gas flow rate (m
3
/h nominal
condition)
P
2
：
Reduced press.(MPa
･
A) t
：
Gas temperature(
℃
)
Δ
P
：
P1
－
P2(MPa) G
：
Specific gravity ( it is against air)
Cv
：
Cv value depend on each size
【
In case of liquid
】
V
：
Max. liquid flow rate (m
3
/h) G:Specific gravity (It is against
water)
Δ P
：
P1
－
P2(MPa)
Cv
：
Cv value depend on each size
Rated Cv value
Size 15A 20A 25A 32A 40A 50A 65A 80A 100A
Rated Cv value 6 9 14 25 33 50 85 106 175
Caution
When selecting pipe size, please take piping condition and application into consideration
and secure a safety rate of 80 %
) P P ( P 138
Wk
Cv
2 1
Δ
2
P
P
1
2
＞
2
P
P
1
2
≦
1
P 120
Wk
Cv
2
P
P
1
2
＞
2
P
P
1
2
≦
) P P ( P
G ) t 273 (
2940
Q
Cv
2 1
Δ
1
P 2550
G ) t 273 ( Q
Cv
P
G V 365 . 0
Cv
Δ