CHECK VALVE
Type CK-1 DN
Port Size 20 - 150mm (3/4" - 4")
Suitable For: Ammonia, R12, R22, R502
and Other Common Refrigerants
Features
• Manual Opening Stem
• Low Pressure Drop
• Piston Type Gravity Closing
• Flanged
• Design Pressure (PS): 28 bar (406 psig)
• Rugged - Heavy Duty
• Body Material made from GGG40.3
• Complies with Pressure Equipment Directive 97/23/EC
Description
These piston type, gravity closing, heavy duty check
valves are suitable for Ammonia, R-12, R-22, R-502,
other refrigerants, certain oils and or fluids approved for
use in refrigeration. All CK1 check valves are flanged and
have a manual opening stem for manual operation. They
may be ordered with male adapter rings (through 4" size)
for close coupling. The 20-32 mm (3/4 - 1-1/4") port size
have a PTFE seat; larger valves have a metal to metal
seat. A minimum pressure difference of .03 bar (0.5 psi)
is required to open the valve.
Fig. 1: CK1-DN Cross-Section
Refrigerating Specialties Division
310227
BULLETIN DN 50-10C
September 2007
Installation, Service, and Parts Information
Purpose
The Type CK1 Check Valves prevent backward flow of
fluid in refrigerant suction, hot gas or liquid lines. They
are recommended for compressor discharge lines, also
for liquid lines and suction lines with temperatures as
low as -30°C (-25°F).
Principles of Operation
This piston type check valve opens by the pressure
difference between valve inlet and outlet. The pressure
difference must be a minimum of .03 bar (0.5 psi).
When upstream pressure exceeds downstream pressure,
the pressure on the bottom side of the piston-main valve
will lift the assembly and allow flow through the valve. On
opening, pressure above the piston-main valve assembly
will be relieved through the piston bleed hole, permitting
the piston to travel its full vertical distance and open the
valve to its full open position.
When upstream and downstream pressures are qualized,
the weight of the piston-main valve will cause it to
drop tight against its seat bead and stop flow. Should
downstream pressure rise, the additional pressure acting
on the top of the valve seat will further assist in seating
the valve closed.
Manual Opening Stem (Fig. 1)
If it is desired to hold open the CK1 check valve manually
this procedure should be followed. For access to the
stem, the seal cap on the bottom of the valve must be
removed. This must be done with caution as refrigerant
may be trapped inside the seal cap. Manual opening is
accomplished by turning the stem clockwise until only
the flats on the end of the stem protrude from the packing
nut. To reset for automatic operation turn the stem
1
ISO 9001 - 2000 CERTIFIED