Valves and flow control
Swing check valve
Automatic prevention of reverse flow
Specialist selection guide
What should be reviewed before selecting this valve?
A swing check valve opens its disc with forward flow and closes automatically on reversal to prevent backflow. Fluid velocity, reverse pressure, installation direction, disc mass and water-hammer risk are central selection factors.
Technical selection path
- 1
Check minimum flow and velocity required to hold the disc open
- 2
Evaluate rapid reversal and water-hammer risk
- 3
Match horizontal or vertical installation to manufacturer design
- 4
Compare pressure loss and closure time for the disc design
- 5
Determine any dashpot, counterweight or external lever requirement
Key strengths
- Automatic operation without external power
- Low pressure loss when fully open
- Suitable for many liquid and gas lines
Selection limitations
- The disc may flutter at low flow
- Delayed closure can generate surge
- Not suitable for every installation orientation
Typical applications
Where can this option be considered?
- Pump discharge and liquid transfer lines
- Backflow prevention in process headers
- Stable-flow lines requiring low pressure loss
Reference standards
A standard does not replace the project specification
ASME B16.34Pressure-temperature ratings, materials, construction, testing and marking requirements for industrial valvesAPI 598Valve inspection, shell pressure testing and seat leakage testingAPI 594Flanged, lug, wafer and butt-welding check valvesASME B16.10Face-to-face and end-to-end valve dimensions
Common technical questions
Concise answers before enquiry
Why can a swing check valve slam?
If flow reverses before the disc seats, rapid closure can create a pressure wave. System velocity and valve closure dynamics must be reviewed together.
Is vertical installation permitted?
Only for the manufacturer-approved flow direction and design. Gravity must assist closure and flow must be sufficient to hold the disc steadily open.
Protecting pumps, compressors and lines where reverse flow is harmful
Minimum flow velocity, water hammer, mounting direction and closing speed
Initial review sheet
Technical attributes to review
Final values must come from project specifications, calculations and manufacturer data. This table defines the information scope.
FamilyManual and mechanical valves
Main groupValves and flow control
Materials to evaluateCarbon steel, Stainless steel, Alloy steel, Cast and ductile iron, Bronze and brass, Special alloys
Connections to evaluateFlanged, Butt-weld, Socket-weld, Threaded, Wafer and lug
Typical mediaProcess liquids, Gas, Steam, Water, Corrosive fluids
Relevant industriesOil and gas, Refining, Petrochemical, Power generation, Water and utilities
Reference standardsASME B16.34 · ASME B16.10 · API 6D · API 600 · API 602 · API 609 · API 598
Enquiry checklist
Include this information with your request
Valve duty
Class and design pressure
Temperature and fluid
Body, trim and seat materials
End connection and face-to-face
Leakage class
Before substitution
A matching name does not guarantee interchangeability
Installation dimensions, pressure rating, wetted materials, sealing design, construction standard, testing and documentation must be checked independently.
Adjacent types
Other options in this family
Final technical approval is required
This page is educational and intended for initial screening. Final selection must be approved against project requirements, actual service conditions and manufacturer documentation.
Send request for review