Grundfos NB - Page 12

2.2.2.1 Letter codes for shaft seals
Pos. 15 in NB, NBG type key example.
Code Description Explanation
B Shaft seal type
A: O-ring seal with fixed
driver
B: Rubber bellows seal
D: O-ring seal, balanced
H: Cartridge seal,
balanced
Q
Material of
rotating seal
face
A: Carbon, metal-
impregnated with antimony
which is not approved for
potable water
B: Carbon, resin-
impregnated
Q: Silicon carbide
Q
Material of
stationary seal
A: Carbon, metal-
impregnated with antimony
which is not approved for
potable water
Q: Silicon carbide
E
Material of
secondary seal
and other rubber
and composite
parts, except the
wear ring
E: EPDM
V: FKM (Viton
®
)
F: FXM (Fluoraz
®
)
K: FFKM (Kalrez
®
)
X: HNBR
U: Dynamic O-rings in
FFKM and static O-rings in
PTFE
For a thorough description of shaft seal types and
materials, see the data booklet "NB, NBG, NK, NKG,
NBE, NBGE, NKE, NKGE - Custom-built pumps
according to EN 733 and ISO 2858".
2.2.2.2
Codes for rated motor power
Pos. 16 in NB, NBG type key example.
Code
Description
[hp] [kW]
A 0.16 0.12
B 0.25 0.18
C 0.33 0.25
D 0.5 0.37
E 0.75 0.55
F 1 0.75
G 1.5 1.1
H 2 1.5
Code
Description
[hp] [kW]
I 3 2.2
J 4 3
K
5 (5.5
1)
) 3.7 (4
1)
)
L 7.5 5.5
M 10 7.5
N 15 11
O 20 15
P 25 18.5
Q 30 22
R 40 30
S 50 37
T 60 45
U 75 55
V 100 75
W 125 90
X
Bare shaft
pump
Y
> 200
2)
> 150
2)
1 150 110
2 175 132
3 200 150
4
215
3)
160
3)
5
250
3)
185
3)
6 26
1)
Value in bracket is for the standard IEC motor size. Value
outside bracket is for the motor size according to NEMA
standards.
2)
Used for pumps where the pump shaft input power exceeds
200 hp (150 kW) and is not regulated under the DOE pump
rule.
3)
Special cases with power sizes above 200 hp (150 kW)
which are still regulated under the DOE pump rule. For
example: Pump has a P2 value of 198 hp (147.6 kW) in its
duty point (in DOE scope) but customer wants the 215 hp
(160 kW) motor instead of the 200 hp (150 kW). The pump
is in scope of the DOE regulation and requires a PEI value
and a motor code.
12
English (GB)