About Backflow-Prevention Valves
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Threaded Check Valves
Male Inlet × Male Outlet
Flared Angle Adapter
Flared Angle Connector
These valves open to allow flow in one direction and close when flow stops or reverses.
316 stainless steel valves have the best corrosion resistance.
Flow coefficient (Cv) is the amount of water (in gallons per minute) at 60° F that will flow through a fully open valve with a difference of 1 psi between the inlet and the outlet.
Adapters, NPT Male Inlet × 37° UN/UNF (JIC) Male Outlet
- For Use With: Air, Argon, Helium, Krypton, Neon, Water, Xenon
- Spring Material: 316 Stainless Steel
- Seal Material: Fluoroelastomer Rubber
| Inlet Pipe Size  | Outlet Thread Size | Flow Coefficient (Cv) | Max. Pressure | Min. Opening Pressure, psi | Temperature Range, °F | End-to-End Lg. | Each | |
316 Stainless Steel Body—Fluoroelastomer Rubber Spring-Loaded Piston | ||||||||
|---|---|---|---|---|---|---|---|---|
| 1/4 | 7/16"-20 | 1.1 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 11/16" | 0000000 | 000000 |
| 3/8 | 9/16"-18 | 3.1 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 11/16" | 0000000 | 00000 |
| 1/2 | 3/4"-16 | 3.8 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 13/16" | 0000000 | 00000 |
| 3/4 | 1 1/16"-12 | 7.4 | 3,000 psi @ 70° F | 2 | -5° to 350° | 4" | 0000000 | 00000 |
| 1 | 1 5/16"-12 | 11.2 | 3,000 psi @ 70° F | 2 | -5° to 350° | 4 5/8" | 0000000 | 000000 |
Connectors, 37° UN/UNF (JIC) Male Inlet × 37° UN/UNF (JIC) Male Outlet
- For Use With: Air, Argon, Helium, Krypton, Neon, Water, Xenon
- Spring Material: 316 Stainless Steel
- Seal Material: Fluoroelastomer Rubber
| Thread Size | Flow Coefficient (Cv) | Max. Pressure | Min. Opening Pressure, psi | Temperature Range, °F | End-to-End Lg. | Each | |
316 Stainless Steel Body—Fluoroelastomer Rubber Spring-Loaded Piston | |||||||
|---|---|---|---|---|---|---|---|
| 7/16"-20 | 1.1 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 9/16" | 0000000 | 000000 |
| 9/16"-18 | 3.1 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 9/16" | 0000000 | 00000 |
| 3/4"-16 | 3.8 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 3/4" | 0000000 | 00000 |
| 1 5/16"-12 | 11.2 | 3,000 psi @ 70° F | 2 | -5° to 350° | 4 7/8" | 0000000 | 000000 |
Adapters, 37° UN/UNF (JIC) Male Inlet × NPT Male Outlet
- For Use With: Air, Argon, Helium, Krypton, Neon, Water, Xenon
- Spring Material: 316 Stainless Steel
- Seal Material: Fluoroelastomer Rubber
| Inlet Thread Size | Outlet Pipe Size | Flow Coefficient (Cv) | Max. Pressure | Min. Opening Pressure, psi | Temperature Range, °F | End-to-End Lg. | Each | |
316 Stainless Steel Body—Fluoroelastomer Rubber Spring-Loaded Piston | ||||||||
|---|---|---|---|---|---|---|---|---|
| 7/16"-20 | 1/4 | 1.1 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 11/16" | 0000000 | 000000 |
| 9/16"-18 | 3/8 | 3.1 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 11/16" | 0000000 | 00000 |
| 3/4"-16 | 1/2 | 3.8 | 3,000 psi @ 70° F | 2 | -5° to 350° | 3 13/16" | 0000000 | 00000 |
Couplers for High-Pressure Fill Valves
Fill tanks and recharge struts—these couplers join hose to high-pressure fill valves with Schrader threads.
Some couplers meet SAE AS4395, an automotive industry standard for flared fitting dimensions.
70° elbow couplers are angled to access hard-to-reach valves.
Couplers with a shut-off valve let you control the flow of air by hand. When used with Schrader valves that have a core, the core depressor pin in these couplers press valves open to let air flow in.
For technical drawings and 3-D models, click on a part number.
Schrader Female Threaded Hose × UN/UNF Male Flared Tube
Straight, Schrader Female
Threaded Hose × UN/UNF
Male Flared Tube
Threaded Hose × UN/UNF
Male Flared Tube
70° Elbow, Schrader
Female Threaded Hose ×
UN/UNF Male Flared Tube
Female Threaded Hose ×
UN/UNF Male Flared Tube
90° Elbow, Schrader
Female Threaded Hose ×
UN/UNF Male Flared Tube
Female Threaded Hose ×
UN/UNF Male Flared Tube
Inlet | Outlet | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thread Size | Material | Thread Size | Material | Flared Angle | For Tube OD | Material | Max. Pressure, psi | Temp. Range, °F | Features | Specifications Met | Each | |
Straight | ||||||||||||
| 0.305"-32 | Zinc-Plated Steel | 7/16"-20 | Stainless Steel | 37° | 1/4" | __ | 5,000 | -20° to 250° | __ | SAE AS4395 | 000000 | 000000 |
70° Elbow | ||||||||||||
| 0.305"-32 | __ | 7/16"-20 | __ | 37° | 1/4" | Brass | 5,000 | Not Rated | __ | __ | 000000 | 00000 |
90° Elbow with a Shut-Off Valve | ||||||||||||
| 0.305"-32 | __ | 3/8"-24 | __ | 37° | 3/16" | Brass | 3,000 | -40° to 160° | Core Depressor Pin | SAE AS4395 | 000000 | 00000 |
| 0.485"-26 | __ | 3/8"-24 | __ | 37° | 3/16" | Brass | 3,000 | -40° to 160° | Core Depressor Pin | __ | 000000 | 00000 |
Backflow-Prevention Inline Hydraulic Valves
Also known as check valves, these open to allow flow in one direction and close when flow stops or reverses.
Valves with a poppet have internal components that can handle any flow rates. The higher the flow rate of the hydraulic fluid coming into the valve, the lower the pressure the fluid is as it leaves the valve.
UN/UNF (SAE Straight) thread connections have straight threads and are also known as O-ring Boss fittings.
For technical drawings and 3-D models, click on a part number.
UN/UNF (SAE Straight) Male Inlet × UN/UNF (JIC) Male Outlet—Poppet Check Valve
UN/UNF
(SAE Straight)
— UN/UNF (JIC)
(SAE Straight)
— UN/UNF (JIC)
Inlet Connection | Outlet Connection | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thread Size | Dash Size | Thread Size | Dash Size | Flared Angle | Max. Flow Rate | Flow Coefficient (Cv) | Max. Pressure, psi | Min. Opening Pressure, psi | Seal Material | Port-to-Port Lg. | Hex Wd. | Mounting Orientation | Temp. Range, °F | Each | |
Steel Body | |||||||||||||||
| 7/16"-20 | 04 | 7/16"-20 | 04 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 1/4" | 9/16" | Any Position | -40° to 250° | 0000000 | 000000 |
| 9/16"-18 | 06 | 9/16"-18 | 06 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 1/4" | 3/4" | Any Position | -40° to 250° | 0000000 | 00000 |
| 3/4"-16 | 08 | 3/4"-16 | 08 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 5/8" | 7/8" | Any Position | -40° to 250° | 0000000 | 00000 |
| 7/8"-14 | 10 | 7/8"-14 | 10 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 7/8" | 1" | Any Position | -40° to 250° | 0000000 | 000000 |
| 1 1/16"-12 | 12 | 1 1/16"-12 | 12 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 2 1/8" | 1 1/4" | Any Position | -40° to 250° | 0000000 | 000000 |
| 1 5/16"-12 | 16 | 1 5/16"-12 | 16 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 2 1/2" | 1 1/2" | Any Position | -40° to 250° | 0000000 | 000000 |
UN/UNF (JIC) Male Inlet × UN/UNF (SAE Straight) Male Outlet—Poppet Check Valve
UN/UNF (JIC) — UN/UNF (SAE Straight)
Inlet Connection | Outlet Connection | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thread Size | Dash Size | Flared Angle | Thread Size | Dash Size | Max. Flow Rate | Flow Coefficient (Cv) | Max. Pressure, psi | Min. Opening Pressure, psi | Seal Material | Port-to-Port Lg. | Hex Wd. | Mounting Orientation | Temp. Range, °F | Each | |
Steel Body | |||||||||||||||
| 7/16"-20 | 04 | 37° | 7/16"-20 | 04 | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 1/4" | 9/16" | Any Position | -40° to 250° | 0000000 | 000000 |
| 9/16"-18 | 06 | 37° | 9/16"-18 | 06 | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 1/4" | 3/4" | Any Position | -40° to 250° | 0000000 | 00000 |
| 3/4"-16 | 08 | 37° | 3/4"-16 | 08 | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 5/8" | 7/8" | Any Position | -40° to 250° | 0000000 | 00000 |
| 7/8"-14 | 10 | 37° | 7/8"-14 | 10 | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 7/8" | 1" | Any Position | -40° to 250° | 0000000 | 000000 |
| 1 1/16"-12 | 12 | 37° | 1 1/16"-12 | 12 | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 2 1/8" | 1 1/4" | Any Position | -40° to 250° | 0000000 | 000000 |
| 1 5/16"-12 | 16 | 37° | 1 5/16"-12 | 16 | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 2 1/2" | 1 1/2" | Any Position | -40° to 250° | 0000000 | 000000 |
UN/UNF (JIC) Male Inlet × UN/UNF (JIC) Male Outlet—Poppet Check Valve
UN/UNF (JIC) — UN/UNF (JIC)
Inlet Connection | Outlet Connection | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thread Size | Dash Size | Flared Angle | Thread Size | Dash Size | Flared Angle | Max. Flow Rate | Flow Coefficient (Cv) | Max. Pressure, psi | Min. Opening Pressure, psi | Seal Material | Port-to-Port Lg. | Hex Wd. | Mounting Orientation | Temp. Range, °F | Each | |
Steel Body | ||||||||||||||||
| 7/16"-20 | 04 | 37° | 7/16"-20 | 04 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 1/2" | 9/16" | Any Position | -40° to 250° | 0000000 | 000000 |
| 9/16"-18 | 06 | 37° | 9/16"-18 | 06 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 1/2" | 3/4" | Any Position | -40° to 250° | 0000000 | 00000 |
| 3/4"-16 | 08 | 37° | 3/4"-16 | 08 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 1 7/8" | 7/8" | Any Position | -40° to 250° | 0000000 | 00000 |
| 7/8"-14 | 10 | 37° | 7/8"-14 | 10 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 2" | 1" | Any Position | -40° to 250° | 0000000 | 000000 |
| 1 1/16"-12 | 12 | 37° | 1 1/16"-12 | 12 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 2 1/2" | 1 1/4" | Any Position | -40° to 250° | 0000000 | 000000 |
| 1 5/16"-12 | 16 | 37° | 1 5/16"-12 | 16 | 37° | Not Rated | Not Rated | 5,000 | 5 | Buna-N Rubber | 2 5/8" | 1 1/2" | Any Position | -40° to 250° | 0000000 | 000000 |