NRVA15/20-NRVA25/32-NRVA40/50-DN65 Danfoss Check valves

NRVA15/20-NRVA25/32-NRVA40/50-DN65 Danfoss Check valves

Check valve type NRVA can be used in liquid,
suction and hot gas lines in refrigeration and air
conditioning plant with ammonia.
NRVA can also be used in refrigerating systems
with fluorinated refrigerants.
When the NRVA is used in liquid lines where
cold, thick oil or impurities may be present, it
is recommended that the standard spring be
replaced by a special spring. See ordering table.

Ensures correct direction of flow.
• Valve housing made of steel.
• Available for 40 bar g / 580 psig working
pressure.
• Large range of flanges with connection dimen-
sions in accordance with standards: DIN, ANSI,
SOC, SA and FPT.
• Fitted with damping piston that makes the
valves suitable for installation in lines where
pulsation can occur, e.g. in the discharge line
from the compressor.
• Classification: DNV, CRN, BV, EAC etc.
To get an updated list of certification on the
products please contact your local Danfoss
Sales Company.
Design Connections
There is a very wide range of connection
possibilities with NRVA check valves:
• Welding, DIN (2448)
• Welding, ANSI (B 36.10)
• Welding socket, ANSI (B 16.11)
• Solder connection, DIN (2856)
• Solder connection, ANSI (B 16.22)
• FPT internal thread, NPT
(ANSI/ASME B 1.20.1)
Gaskets:
Do not contain asbestos.
Valve cone:
The valve cone has a teflon tightening ring.
Teflon tightening ring renders perfect sealing at a
minimum closing force.

Complete valves incl. DIN 2448 flange:
Type
Weld flange
connection
Code no. Dp  2 )
k v value  3 ) C v value  4 )
Valve Spec. spring  1 )
With
standard spring
With
spec. spring  1 )
in. bar psig bar psig m 3 /h gal/min
NRVA 15
1 /
2
020-2000 020-2307 0.12 1.7 0.3 4.4 5 6
NRVA 20
3 /
4
020-2001 020-2307 0.12 1.7 0.3 4.4 6 7
NRVA 25 1 020-2002 020-2317 0.12 1.7 0.3 4.4 19 22
NRVA 32 1  1 / 4 020-2003 020-2317 0.12 1.7 0.3 4.4 20 23
NRVA 40 1  1 / 2 020-2004 020-2327 0.07 1.0 0.4 5.8 44 51
NRVA 50 2 020-2005 020-2327 0.07 1.0 0.4 5.8 44 51
NRVA 65 2  1 / 2 020-2006 020-2337 0.07 1.0 0.4 5.8 75 87
1 ) A special type spring can be supplied to replace the standard valve spring.
2 ) Dp = the minimum pressure differential at which the valve is completely open.
3 ) The k
v value is the flow of water in m
3 /h at a pressure drop across valve of 1 bar, ρ = 1000 kg/m 3 .
4 ) The C
v value is the flow of water in gal/min at a pressure drop across valve of 1 psig, ρ = 10 lbs/gal.
Valve body without flanges:
Type Code no.
NRVA 15 020-2020
NRVA 20 020-2020
NRVA 25 020-2022
NRVA 32 020-2022
NRVA 40 020-2024
NRVA 50 020-2024
NRVA 65 020-2026
Staybolts and gaskets
Type Dimensions Code no.
NRVA 15 / 20 M 12 × 115 mm 006-1107
NRVA 25 / 32 M 12 × 148 mm 006-1135
NRVA 40 / 50 M 12 × 167 mm 006-1137
NRVA 65 M 16 × 200 mm 006-1138