Can the Screw-in check valve, used in hydraulic systems, type FPRI, be installed in either flow direction by relocating the supplied O-ring?

Yes. The Screw-in check valve, used in hydraulic systems, type FPRI is designed to allow installation for either flow direction by repositioning the supplied Oâring. The valve provides one-way closure in one direction and free flow in the opposite; by fitting the Oâring on the side corresponding to the desired sealed direction, you change which port is closed at rest. Ensure the Oâring is correctly seated and undamaged, install the valve into a suitably deep threaded hole, and respect the specified orientation for permissible flow A â A1 when configuring. Standard opening pressure is 0.5 bar; materials and sealing (galvanized steel, hardened steel stem, NBR) and temperature range (â20Â°C to +100Â°C) remain unchanged.

Does the Screw-in check valve, used in hydraulic systems, type FPRI, support higher opening pressures than the standard 0.5 bar?

Screw-in check valve, used in hydraulic systems, type FPRI has a standard opening pressure of 0.5 bar. The provided description does not state any adjustable or alternative spring options or variants that would allow higher opening pressures. Therefore, based solely on the given information, the FPRI supports an opening pressure of 0.5 bar; any higher opening pressure would require a different model or a modified/version specified by the manufacturer.

Is the Screw-in check valve, used in hydraulic systems, type FPRI, compatible with fluids other than mineral oil?

Screw-in check valve, used in hydraulic systems, type FPRI is designed and specified for use with mineral oilâbased hydraulic fluids. Its sealing material is NBR (nitrile rubber), and the body and stem are steel (galvanized and hardened). Compatibility with other fluids depends primarily on NBRâs chemical and temperature resistance: - NBR is generally compatible with: mineral oils, petroleum-based hydraulic fluids, some vegetable oils (limited), and some water-glycol fluids at low concentrations. - NBR is not recommended with: phosphate esters (e.g., Skydrol), some synthetic esters, many silicone fluids, ketones, strong oxidizers, and some aggressive solvents (e.g., aromatics, chlorinated hydrocarbons). - Temperature range given (â20Â°C to +100Â°C) limits use with fluids requiring higher or lower operating temperatures. Conclusion: Screw-in check valve, used in hydraulic systems, type FPRI may be used with fluids other than mineral oil only if those fluids are chemically compatible with NBR and operate within â20Â°C to +100Â°C. For phosphate esters, many synthetics, silicone fluids or other aggressive media, choose a valve with a compatible seal material (e.g., FKM/Viton, EPDM) or consult the valve manufacturer for confirmed compatibility.

Screw-in check valve, used in hydraulic systems, type FPRI

All products, Directional control valves/

Additional information

Material	CS – steel (cast iron)

FPRI type check valve used in hydraulic systems as a component for closing the flow of hydraulic fluid in one direction and allowing free flow of fluid in the opposite direction. Designed to be screwed into a suitably deep threaded hole. Supplied with an O-ring, which serves as a seal between the valve and the threaded hole. The O-ring can be installed on either side of the valve (depending on the flow direction desired). Standard opening pressure: 0.5 bar. Permissible flow direction A → A1. Material: galvanized steel (body), hardened steel (stem). Sealing: NBR. Operating temperature: from -20°C to +100°C.

List of product variants

Article number	Product variant name	DN	BAR	Availability	Actions
DC-FPRI-04	FPRI GZ 1/4" check valve	-	350	In stock	Enquiry
DC-FPRI-06	FPRI GZ 3/8" check valve	-	350	In stock	Enquiry
DC-FPRI-08	FPRI GZ 1/2" check valve	-	350	In stock	Enquiry
DC-FPRI-12	FPRI GZ 3/4" check valve	-	350	In stock	Enquiry

Do you need a larger quantity of products or a bespoke quote?

Call us: +48 61 653 02 22 or email us: tubes@tubes-international.com

SEND ENQUIRY

FPRI type check valve used in hydraulic systems as a component for closing the flow of hydraulic fluid in one direction and allowing free flow of fluid in the opposite direction. Designed to be screwed into a suitably deep threaded hole. Supplied with an O-ring, which serves as a seal between the valve and the threaded hole. The O-ring can be installed on either side of the valve (depending on the flow direction desired). Standard opening pressure: 0.5 bar. Permissible flow direction A → A1. Material: galvanized steel (body), hardened steel (stem). Sealing: NBR. Operating temperature: from -20°C to +100°C.