NAF-Check check valves are ideal for liquid, gas and steam piping systems. The valves have a fast opening and closing time, which is invaluable in applications where space is limited. The NAF-Check valves are made of light weight disc, which reduce water hammer and also have excellent tightness. The valves are CE-marked according to Pressure Equipment Directive (PED 97/23/EG) module H, category III.
This document provides technical data for the NAF-Check tilting disc check valve, available in DN 40 to 1000 sizes and PN 10 to PN 40 pressure classes. The valves are manufactured in carbon steel or stainless steel and are suitable for BS, DIN, SS, ANSI, and API standards. Key features include a short face-to-face length, low pressure drop, and excellent tightness exceeding API 598 requirements.
| Valve Type | NAF-Check Tilting Disc Check Valve |
|---|---|
| Size Range | DN 40 - 1000 |
| Pressure Class Range | PN 10 - PN 40 |
| Temperature Range | -30 - 350°C |
| Standards | BS, DIN, SS, ANSI, API |
| Tightness Standard | Better than API 598 |
Valves with an auxiliary spring are recommended for use in liquid flow to reduce water hammer.
The valve stays fully open with a water velocity of only 0.6 m/s when it does not have an auxiliary spring.
Adding an auxiliary spring reduces water hammering to one fourth that obtained using springless valves.
The valves are rated for a temperature range from -30°C up to 350°C.