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Provides unidirectional flow and tight shut-off for liquids and gas with high reliability. When differential drops below cracking pressure*, valve shuts off. (Not for use as relief valve.)

Materials: 316 Stainless Steel: body, cover, poppet, cover gland. 300 Series Stainless Steel: spring Standard O-ring: Viton, for operation to 400° F (204°C). Buna-N or Teflon available for 250°F (121°C) or 400°F (204°C) respectively; specify when ordering.

*Cracking Pressure: 20 psi (1.38 bar) ±30%. Springs for higher cracking pressures (up to 100 psi (6.89 bar)) available on special order for O-ring style check valves only.

Minimum operating temperature for standard o-ring check valves 0°F (-17.8°C).
Check Flow - water, GPM
For flow rates using alternate fluids, consult Autoclave Engineers.

CAUTION: While testing has shown O-Rings to provide satisfactory service life, both cyclic and shelf life may vary widely with differing service conditions, properties of reactants, pressure and temperature cycling and age of the O-ring. FREQUENT INSPECTIONS SHOULD BE MADE to detect any deterioration, and O-rings replaced as required.

NOTE: NPT (Pipe) Connections:
- NPT threads must be sealed using a high quality PTFE tape and/or paste product. Refer to thread sealant manufacturer's instructions on how to apply thread sealant.
- Sealing performance may vary based on many factors such as pressure, temperature, media, thread quality, thread material, proper thread engagement and proper use of thread sealant.
- Customer should limit the number of times an NPT fitting is assembled and disassembled because thread deformation during assembly will result in deteriorating seal quality over time. When using only PTFE tape, consider using thread lubrication to prevent galling of mating parts.
P_check_o_ring
P_check_dim
Unit of Measure
1 

Item #

Connection Type

Pressure Rating

Minimum Opening

Rated Cv

CPO4400 N/A 1/4" NPT N/A 15.000 psi1034.20 bar N/A 0.12 in3.05 mm N/A 0.28
CPO6600 N/A 3/8" NPT N/A 15.000 psi1034.20 bar N/A 0.22 in5.59 mm N/A 0.84
CPO8800 N/A 1/2" NPT N/A 15.000 psi1034.20 bar N/A 0.36 in9.14 mm N/A 2.30
CPO12 N/A 3/4" NPT N/A 10.000 psi689.46 bar N/A 0.52 in13.21 mm N/A 4.70
CPO16 N/A 1" NPT N/A 10.000 psi689.46 bar N/A 0.69 in17.53 mm N/A 7.40
Unit of Measure
1