The check valve is appointed for installation in circular air conductors to cut off the air flow and prevent its reverse movement.
The duct check valve for round ducts type D-ZKK-100 is developed to avoid air rotation and non-explosive air mixtures (which are not aggressive, not exceeding the aggressiveness of air with a temperature of up to 60°C, and do not contain fibrous materials, while the content of dust and other solid impurities does not exceed 100 mg/m³).
The main purpose of the valve is to prevent outside air and precipitation from flowing into the premises when the fans are turned off.
The check valve consists of blades, a casing and a spring.
When there is no airflow (when the fan is off), the blades are automatically closed by a spring. When the fan is running, the airflow pressure opens the valve.
The valve is mounted on horizontal sections of air conductors, while the air velocity passing through the valve cross-section should remain in the range from 1.5 to 8 m/s.
When installing valves in vertical air conductors, the air flow should be directed from the bottom up, and the air velocity passing through the valve cross-section should remain within 2.5 to 8 m/s.
| Type measurement | Dimensions, mm | Weight in kg | ||
| D | B | C | ||
| D-ZKK-ІОО | 100 | 50 | 80 | 0,23 |
| D-ZKK-І25 | 125 | 50 | 100 | 0,3 |
| D-ZKK-150 | 150 | 60 | 120 | 0,43 |
| D-ZKK-160 | 160 | 60 | 120 | 0,47 |
| D-ZKK-200 | 200 | 80 | 140 | 0,7 |
| D-ZKK-250 | 250 | 80 | 140 | 0,93 |
| D-ZKK-315 | 315 | 80 | 140 | 1,43 |
