Specification Sheet

Non-return valves, type GNV
5
Grundfos valves
2
2. Non-return valves, type GNV
GNV non-return valves are designed for installation in
pipe systems between two DIN flanges. The valve
casing is made of electro-coated cast iron. Valve cone,
valve seat and other components are made of
stainless steel.
Applications
GNV 50, 80 and 100 are used in Grundfos booster
systems, in water supply systems and drainage
systems in both dwelling houses and in industry where
a one-way water flow is required.
Construction
The choice of materials reduces wear and corrosion to
a minimum and ensures long maintenance-free life.
The valve seat consists of a stainless-steel ring on
which synthetic rubber has been vulcanised. Due to
this construction, the valve cone is seated directly on
the stainless-steel ring at high pressures, to relieve the
pressure on the rubber.
Head loss
Fig. 5 Head loss curves for non-return valves, type GNV
Dimensions and weights
Fig. 6 Dimensional sketch, GNV
Materials
Installation
Fig. 7 Installation example, GNV
The GNV non-return valve is fitted between two DIN
flanges, such as pump flange and counter flange, by
means of bolts and nuts. The valve can be fitted in any
position required. The arrow on the nameplate
indicates the direction of the water flow.
Before installation, gaskets should be fitted on either
side of the valve. The following sizes should be used:
Maximum operating pressure: 25 bar (PN 25).
Liquid temperature: 0 °C to +120 °C.
TM00 4290 2394TM00 0549 4697
GNV
Type
D1
[mm]
D2
[mm]
D3
[mm]
B
[mm]
Weights
[kg]
Product
numbers
GNV
DN 50 (2")
65 50 104 48 1.4 957521
GNV
DN 80 (3")
80 70 128 93 2.7 957526
GNV
DN 100 (4")
100 95 160 95 5.0 957541
Valve components Materials DIN W.-No.
Valve casing, electro-coated Cast iron 0.6020
Valve seat, vulcanised Stainless steel, NBR 1.4301
Guide for valve seat,
electro-coated
Cast iron 0.6020
Valve cone Stainless steel 1.4301
Guide complete Stainless steel 1.4301
Spring Stainless steel 1.4301
Spring retainer Stainless steel 1.4401
TM00 0551 3292
Valve type Gasket size
GNV 50 ∅102 / ∅65 mm x 1.5 mm
GNV 80 ∅125 / ∅80 mm x 1.5 mm
GNV 100 ∅162 / ∅115 mm x 2.0 mm