Val-Matic Swing-Flex Check Valve - Manual (Page 3)

Table 1. Flange Bolt Torques
Valve Bolt Recom. Max.
Size Dia Torque Torque
(in) (in) (ft-lbs) (ft-lbs)
3
5/8 25 90
4 5/8 25 90
6 3/4 30 150
8 3/4 40 150
10 7/8 45 205
12 7/8 65 205
14 1 80 300
16 1 80 300
18 1 1/8 100 425
20 1 1/8 100 425
24 1 1/4 150 600
30 1 1/4 160 600
36 1 1/2 300 900
42 1 1/2 300 900
48 1 1/2 300 1,000
Item Description Material
1
Body Ductile Iron – 250 psi
Cast Iron – 150 psi
2 Cover Ductile Iron – 250 psi
Cast Iron – 150 psi
3 Disc* Steel With Buna-N Facing
4 Cover Seal* Buna-N or Non-Asbestos
5 Cover Bolt Alloy Steel
*Recommended Spare Part
INSTALLATION
Correct installation of the Swing-Flex  is important
for proper operation. It may be installed in either
horizontal or vertical flow-up applications.
However, when horizontal, the valve must be
installed with the nameplate facing up and the
cover level. In all installations, the flow arrow cast
in the valve cover must be pointed in the direction
of flow during normal system operation.
FLANGED ENDS: Flanged valves should only be
mated with flat-faced pipe flanges equipped with
full-face resilient gaskets. The valve and adjacent
piping must be supported and aligned to prevent
cantilevered stress on the valve. Once the flange
bolts or studs are lubricated and inserted around
the flange, tighten them uniformly hand tight. The
tightening of the bolts should then be done in
graduated steps using the crossover tightening
method. Recommended lubricated torque values
for use with resilient gaskets (75 durometer) are
given in Table 1. If leakage occurs, allow gaskets
to absorb fluid and check torque and leakage after
24 hours. Do not exceed bolt rating or extrude
gasket.
VALVE CONSTRUCTION
The standard Swing-Flex  Check Valve is
constructed of rugged cast iron with a rubber
encapsulated disc. See the specific Materials List
submitted for the order if other than standard cast
iron construction. The disc is the only moving part
assuring long life with minimal maintenance. The
general details of construction are illustrated in
Figure 2. The body (1) is flanged for connection to
the pipeline with an open top sealed with a cast
cover (2). The disc (3) is retained by the cover.
FIGURE 2. CHECK VALVE CONSTRUCTION
MAINTENANCE
The Swing Flex

Check Valve requires no
scheduled lubrication or maintenance. For service
or inspection, the valve can be serviced without
removal from the line.
VALVE INSPECTION: If inspection of the valve is
required, follow the Disassembly Instructions given
on page 3.
WARNING
Do not use threaded holes in cover for
lifting the valve. Serious injury may result.
CAUTION
The use of ring gaskets or excessive bolt
torque may damage valve flanges.