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Available Drag Disks
The FSW-50 Series Switches come with three different drag disks. The
drag disks are sized as follows:
DRAGDISK SIZE
#1 .5" dia.
#2 .83" dia.
#3 1.0" dia.
The following table lists flow adjustment limits for various pipe sizes
relative to Model No. and drag disk size. The moment arm (see Step 3 of
FLOWRANGE) is held constant at the maximum value. Decreasing the
moment arm, increases the adjustment range.
Low Flow Nominal Pipe Nominal High Flow % Increase
Model Low Flow Size HighFlow Model of Listed
Number Cont. Adj. (Ins.) Cont. Adj. Number Flows via
Range Range Moment
(GPM) (GPM) Arm Adj.
FSW-50 w/drag * ** * ** FSW-50 w/drag
disk #2 8-13 1 18-28 disk #1 None
Shortest drag Shortest drag
disk arm. disk arm.
Mid. size 3.3-5.3 7.4-11.5 Smallest drag
drag disk ft/sec ft/sec disk
FSW-51 w/drag 15-30 11/230-60 FSW-51 w/drag
disk #3 25-50 2 50-105 disk #1 None
40-80 21/280-155
Mid. size Mid. size
drag disk drag disk
arm. Largest 2.7-5.4 5.4-10.8 arm. Smallest
drag disk ft/sec ft/sec drag disk
FSW-52 w/drag 40-90 3 90-180 FSW-52 w/drag
disk #3 60-120 31/2120-240 disk #1 +25%
75-155 4 155-310
Longest drag 120-245 5 245-480 Longest drag
disk arm. 180-350 6 350-700 disk arm.
Largest 300-600 8 600-1200 Smallest
drag disk 500-950 10 950-1900 drag disk
2.4-4.0 4.0-8.0
ft/sec ft/sec
**Force/Balance spring relaxed.
**Force/Balance spring fully extended.
Notes
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