Check Valve
A check valve permits flow in one direction only and closes automatically to prevent backflow. It protects pumps, meters and clean loops from reverse flow.
What is a Check Valve
A swing, spring or duckbill element opens with forward flow and reseats when flow reverses. It cannot lock a line closed — use a ball or butterfly valve for isolation and a check valve only for backflow protection.
Materials & standards
- 316L stainless steel body
- PTFE or EPDM seat
- Tri-clamp (3A) or flange ends
- Spring-loaded options for low cracking pressure
- Sanitary and industrial versions
Typical applications
- Backflow protection for pumps and meters
- CIP supply and return separation
- Dairy and beverage lines
- Pharma and biotech utility loops
- Compressed-air and process lines
Check Valve at a glance
| Sealing | Reseats on reverse flow |
|---|---|
| Cleanability | Good in hygienic versions |
| Relative cost | Low |
| Best use | One-way flow / backflow protection only |
Frequently asked questions
Can a check valve isolate a line for maintenance?
No. A check valve only prevents backflow; it cannot lock a line closed. Use a ball or butterfly valve for isolation.
What cracking pressure do I need?
Spring-loaded check valves can be set for low cracking pressure to protect sensitive pumps; specify by duty.
Are sanitary check valves 3A?
Yes, tri-clamp 316L hygienic check valves are built to 3A practice for food, dairy and pharma.
Last updated: 2026-10-08
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