In fluid systems, preventing backflow is critical for protecting pumps, maintaining pressure, and ensuring clean, efficient operation. This is where check valves, also known as non-return valves (NRVs), come in. A check valve allows fluid to flow in one direction only, automatically stopping reverse flow without the need for manual operation.

While the term “check valve” is commonly used in the United States, “non-return valve” is often used internationally. Regardless of the name, the function is the same. Below, we break down the main types of check valves and where they are typically used.

Types of Check Valves

1. Swing Check Valve

A swing check valve uses a hinged disc that swings open with forward flow and closes when flow reverses.

  • Common Uses: Water distribution systems, large pumps, irrigation lines.

2. Lift Check Valve

This type relies on a guided disc or piston that lifts with forward flow and drops back into place when flow stops.

  • Common Uses: High-pressure pipelines, steam and gas systems, vertical installations.

3. Ball Check Valve

A ball moves off its seat to allow flow and seals back into place to prevent backflow.

  • Common Uses: Wastewater, sewage systems, pumping stations, slurries, and viscous fluids.

4. Spring-Loaded (In-Line) Check Valve

A spring holds the valve shut until forward flow compresses the spring to allow passage. Reverse flow pushes it shut quickly.

  • Common Uses: Domestic plumbing, industrial process lines, compact systems requiring fast closure.

5. Dual Plate / Wafer Check Valve

Designed with two half-discs that pivot open with flow and close quickly against reverse flow.

  • Common Uses: Large-diameter pipelines, oil and gas industries, HVAC chilled water systems.

6. Diaphragm Check Valve

A flexible diaphragm opens with flow and seals tightly when flow reverses.

  • Common Uses: Low-pressure systems, chemical processing, corrosive or abrasive fluids.

Check Valves in PVC Systems

For PVC piping systems, such as irrigation, water transfer, and residential plumbing, swing check valves and spring-loaded check valves are the most widely used. They are reliable, easy to install, and provide long-term durability in systems designed for cold water under pressure.

Why Check Valves Matter

Using the right check valve prevents costly issues like water hammer, pump damage, and contamination from reverse flow. Whether you call them check valves or non-return valves, they play an essential role in protecting your system and keeping fluid moving in the right direction.

At 247Garden, we carry a range of PVC fittings and components designed to help you build reliable, leak-free systems. Choosing the right check valve ensures efficiency, safety, and long-term performance.

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