1. One-Way Flow: Check valves permit fluid to flow in one direction only. They automatically close to prevent reverse flow or backflow.
  2. Mechanical Operation: They operate based on the pressure of the fluid flowing through them, typically using a spring-loaded mechanism or the pressure of the fluid itself to close the valve when flow reverses.
  3. Types of Check Valves: Common types include swing check valves, which use a hinged disc to block reverse flow; ball check valves, which use a spherical ball to achieve the same purpose; and lift check valves, where a disc or piston moves in response to flow.

Applications:

Importance: