The table below can be used to estimate a Cv if
the orifice size is known or, conversely, to relate the
approximate orifice size if the Cv is known. The
chart is based on the ASCO designs of inline
globe type valves.
The flow charts must be used for precise sizing
and converting Cv factors to actual flow terms,
and the catalog must be consulted for the actual
Cv of a particular valve.
|
Approximate Orifice Size (ins.) |
Approximate Cv |
|
1/32 |
.02 |
|
3/64 |
.06 |
|
1/16 |
.09 |
|
3/32 |
.20 |
|
1/8 |
.30 |
|
9/64 |
.36 |
|
3/16 |
.53 |
|
1/4 |
.70 |
|
5/16 |
1.7 |
|
3/8 |
2 |
|
1/2 |
3.5 |
|
5/8 |
4.5 |
|
11/16 |
5 |
|
3/4 |
7.5 |
|
1 |
13 |
|
1 1/4 |
17 |
|
1 1/2 |
25 |
|
2 |
48 |
|
2 1/2 |
60 |
|
3 |
100 |