Cla-Val 340-02/3640-02 - Manual (Page 24)

A flow range:
Select the sizing chart that matches pipe size and locate required flow range between the minimum and maximum limits of an
orifice bore. Frequently the flow range will fit between more than one bore size. To resolve this, decide the flow rate that
system will be operated at most frequently. Locate the flow which is closest to this under the nominal flow column, and
select the corresponding bore size dimension.
6" Valve / Pipe Size
Bore
Size
Flow - gpm
Min. Max. Nominal
4.60 490 1960 1100
4.40 435 1740 980
4.20 380 1520 850
4.00 330 1320 750
3.80 300 1200 670
3.60 265 1060 590
3.40 230 920 520
3.20 200 800 450
3.00 175 700 395
2.80 150 600 340
2.60 130 520 295
2.40 110 440 245
6" Valve / Pipe Size
Bore
Size
Flow - gpm
Min. Max. Nominal
4.60 490 1960 1100
4.40 435 1740 980
4.20 380 1520 850
4.00 330 1320 750
3.80 300 1200 670
3.60 265 1060 590
3.40 230 920 520
3.20 200 800 450
3.00 175 700 395
2.80 150 600 340
2.60 130 520 295
2.40 110 440 245
2 1 ⁄
2
" Valve / Pipe Size
Bore
Size
Flow - gpm
Min. Max. Nominal
1.87 80 330 180
1.60 55 220 120
1.40 40 160 88
1.20 28 115 62
1.00 19 80 43
.80 12 50 28
2" Valve / Pipe Size
Bore
Size
Flow - gpm
Min. Max. Nominal
1.55 55 220 125
1.50 50 200 115
1.40 42 168 95
1.20 29 116 65
1.00 19 76 45
.80 12 50 28
*For 1 1/2 " bore information please consult the factory
1. In determining a bore size, the nominal flow rate (or range of flow) and the pipe size in which the orifice plate assembly will
be installed must be known.
2. Sizing a bore for:
A constant flow rate:
Select the sizing chart that matches pipe size and locate the flow rate under the nominal column which is closest to
required flow; select the corresponding bore size dimension.
Sizing An Orifice Plate Bore
Orifice Plate Bore Chart
Example:
A 6" pipe with a desired constant flow of 700 gpm .
Using the 6" chart, the closest flow in the nominal
column is 670
gpm which has a corresponding bore
size of 3.80".
Example:
A 6" pipe with a flow range of 300-1000 gpm. Using
the 6" chart, more than one bore size can accom-
modate this range. The most frequent flow rate will
be 500 gpm. Using the nominal flow column, the
closest flow is 520 gpm which has a corresponding
bore size of 3.40"