Check Valves
are available in numerous types, styles and
shapes. Generally a Valve manufacturer builds
only of check valve. VALWORTH
builds three types. Therefore, we offer the
consulting engineer open, objective and unbiased
information about a broad rang of check valves
and their proper selection and application.
The purpose of this brochure is to collect
and condense the many desirable features of
the most common type checks into a single
source.
Although check
valves look different, they each perform the
same basic function which is flow through
one direction and no flow (check) return.
Check valves are commonly installed on the
discharge side of the pump . The most important
role of check valve is to act as the automatic
shut off valve, when the pumps stops to prevent
draining of the system which the pump fills.
However, each check valve has different shut-off
characteristics. This brochure reviews these
characteristics to help you select the best
check valve for your Project.
APPLICATIONS
PUMPS
STEAM
AIR
GAS
WATER
OIL
VACUUM LINES
CHEMICAL
OTHER
APPLICABLE STANDARDS
Valworth Wafer type check
Valves design to conform To the following
standard where applicable.
API
6D I ANSI B 16. 10
Design and
Face-to-Face dimensions.
API
594
Wafer type
check valve
API
598
Valve Inspection
& Testing.
DIN
3230
Testing
Standards.
DIN
EN 558 – 2
Design Standard.
ANSI
B16.5
Flanges
End connections.
TEST
PRESSURE FOR VALVES
Class
min. Test Pressure Psi(g)
Shell Hydro
Seat Hydro
Air Seat
150#
425
300
80
300#
1100
800
80
400#
1450
1060
80
600#
2175
1600
80
MINIMUM DURATION OF TEST
PRESSURE
SIZE
DURATION
SHELL
SECONDS
12” & SMALLER
60
60
14” & LARGER
120
120
MAXIMUM ALLOWABLE LEAKAGE AS PER API 594
The maximum permissible leakage rate for
Metal seated valves shall be 0.18 cubic inches(3
cubic centimeters) per minute per inch of
nominal valve size. The leakage rate for resilient
seated valves shall be zero.
