Split Coupled Vertical In-Line Pumps - Northam Inc
                     NL-S SERIES
SPLIT COUPLED 
VERTICAL IN-LINE PUMPS
AC AD
P
Rp 1/4 Rp 1/4
P
D1
Rp 1/2
D1 G1 G2
G1 G2
ØB
L1
4
4 x Ø18 THRU 5° ØF
PCD
45
°
C650Hz www.northam-inc.com
NL-S SERIES
SPLIT COUPLED VERTICAL IN-LINE PUMPS
PREFACE
The NORTHAM NL-S pumps are single-stage, vertical in-line, split-coupled centrifugal pumps. They have radial 
suction & discharge port, and are coupled with standard NEMA frame electric motors suitable for vertical operation. 
The motor shaft is coupled with pump shaft using a self aligning split coupling which facilitates easy maintainence 
of mechanical shaft seal. 
Vertical in-line pumps offer largest amount of floor space savings compared to equivalent End suction & Horizontal 
split case pumps offering similar performance. When these pumps are installed with Northam Suction Diffusers 
and Triple Duty Valves then space saving in installation is even more.
The in-line construction offers easy pipe work. There is no need for foundation or alignment after installation. Pipe 
hangers sized for the weight of the pump, piping & fittings offers adequate supports for most installations. Pipe 
supports with anti vibration pads  may be installed under suction and discharge pipes or under Suction Diffuser on 
Suction side and Triple Duty Valve under the discharge side for additional support.
Standard flanges for suction & discharge ports will be ANSI 125 or ANSI 250 as per ASME B16.1. PN 16 & PN 25 as 
per DIN standard EN 1092-2 are available on request.
These pumps are provided with NEMA premium efficiency motors complying to meet or exceed the efficiency 
requirements of the U.S. Department of Energy.
Right Angle
Suction Triple Duty 
Diffuser Valve
TYPICAL INSTALLATION WITH SUCTION DIFFUSER & TRIPLE DUTY VALVE
APPLICATIONS
►  Heating, Ventilation and Air-conditioning (HVAC)
►  Pressure boosting
►  Industrial applications
►  Water supply
►  Fire protection systems.
2 Date 20/08/25
Supersedes -
NL-S SERIES
SPLIT COUPLED VERTICAL IN-LINE PUMPS
FEATURES
►  The axially split, spacer type rigid coupling allows for the mechanical shaft seal maintenance without disturbing 
► pump or motor or pipe connections. The split coupling once removed allows for removal of the entire                 
► mechanical seal for servicing or replacement. Reassembly of the split coupling after servicing of mechanical     
► seal ensures that shaft alignment between pump and motor shaft is restored as per required specifications.
►  Heavy and robust design motor adapter provides a rigid connection between the pump casing & motor flange.
►  Generous venting of seal chamber & liquid flushing at seal faces is provided by gland plate flush connections.
►  The pump impellers are dynamically balanced to grade 6.3 of ISO 1940.
►  Rigid volute casing with ribs integrally cast and provided with gauge, flush and drain connections.
►  The pumps can be coupled with NEMA or IEC standard motors suitable for Vertical application.
► Flow straightening vanes in suction area of pump casing ensures superior performance and quiet operation. 
OPERATING RANGE & CONDITIONS
Flow range Up to 9700 GPM
Head range Up to 490 feet
Ambient temperature Max. +140°F for Premium efficiency motors.
PRESSURE vs TEMPERATURE RATINGS
Temperature (°C)
-18 10 38 66 93 121 149 177 204 232 260
400 17
300 14
ANSI 250 & PN 25 FLANGE
200 10
100 7
ANSI 125  & PN 16 FLANGE
0 0
0 50 100 150 200 250 300 350 400 450 500
Temperature (°F)
MOTOR
Motor type NEMA standard induction motor
Ratings Up to 250 HP
Rated speed 1750 or 3450 rpm
Enclosure class IP 55
Insulation class F
Nominal voltages 230/460 volts 3 phase
Supply frequency 60 Hz
Duty / Rating S1 / Continuous
Direction of rotation Clockwise as seen from the motor rear end
PUMPED LIQUIDS
The liquids for which the pump is used should be compatible with wetted parts material of construction including 
mechanical seal.
3 Date 20/08/25
Supersedes -
Maximum total working pressure (psi)
Maximum total working pressure (bar)
NL-S SERIES
SPLIT COUPLED VERTICAL IN-LINE PUMPS
 SECTIONAL DRAWING & MATERIAL OF CONSTRUCTION
03
12
13
10 10
11
01
02 05
04
09 07 08
SPLIT COUPLED VERTICAL IN-LINE PUMP 
ARRANGEMENT WITH INTERNALLY MOUNTED UNBALANCED MECHANICAL SHAFT SEAL
Pos. Component Code-A Code-B
1 Volute casing Cast  iron* Cast  iron*
2 Impeller Cast  iron Bronze
3 Adaptor Cast  iron Cast  iron
5 Pump shaft 410 Stainless steel 410 Stainless steel
7 Impeller washer 410 Stainless steel 410 Stainless steel
8 Impeller locking screw 410 Stainless steel 410 Stainless steel
9 Impeller key 410 Stainless steel 410 Stainless steel
10 Plugs Carbon  steel Carbon  steel
11 O-ring NBR NBR
4 Wear ring Cast Iron Bronze
12 Coupling Aluminum alloy Aluminum aloy
13 Seal housing 410 Stainless steel 410 Stainless steel
* Volute Casing material shall be ductile iron when class 250 or PN 25 flanges are provided.
4 Date 20/08/25
Supersedes -
NL-S SERIES
SPLIT COUPLED VERTICAL IN-LINE PUMPS
 SECTIONAL DRAWING & MATERIAL OF CONSTRUCTION
03
12
13
10
10
11
01
02
05
04
09 07 08
SPLIT COUPLED VERTICAL IN-LINE PUMP 
ARRANGEMENT WITH EXTERNALLY MOUNTED BALANCED MECHANICAL SHAFT SEAL
Pos. Component Code-A Code-B
1 Volute casing Cast  iron* Cast  iron*
2 Impeller Cast  iron Bronze
3 Adaptor Cast  iron Cast  iron
5 Pump shaft 410 Stainless steel 410 Stainless steel
7 Impeller washer 410 Stainless steel 410 Stainless steel
8 Impeller locking screw 410 Stainless steel 410 Stainless steel
9 Impeller key 410 Stainless steel 410 Stainless steel
10 Plugs Carbon  steel Carbon  steel
11 O-ring NBR NBR
4 Wear ring Cast Iron Bronze
12 Coupling Aluminum alloy Aluminum aloy
13 Seal housing 410 Stainless steel 410 Stainless steel
* Volute Casing material shall be ductile iron when class 250 or PN 25 flanges are provided.
5 Date 20/08/25
Supersedes -
NL-S SERIES
SPLIT COUPLED VERTICAL IN-LINE PUMPS
PERFORMANCE RANGE - 60 Hz, 1750 rpm
Capacity - m³/h 
10 20 30 40 50 60 70 80 90 100 200 300 400 500 600 700 800 900 1000 2000
500
400
100
300 90
80
NL N 70NLS-03016 S
200 -04 LS
NL N N
0 -0 S
L
- S- L0 S- 6016 501 60 06 1 8
10
6 01
0
6 16 NLS-12016 50H N
ft NLS-03012
LS- N04 LS 40012 -060 N
NLS-05012 12
LS
100 NL -1
N S 0
30
90 0NLS-01510 LS- NLS-03010
-0
80 0 N 8
1
20 0
2
70 10 NLS-02510
L 1
NL NLS-04010
S- 205 20
60 S 0NLS-01508 NL -S 0 1- NL 40 S 00 020
50 08 -025
8
08 NL NLS-06010S
N -0
40 LS-015 NLS-03008
50
06 NLS-02506
08
NLS-06008 10
30 9
8
NLS-03006
NLS-02006 7
20 6
5
4
10 3
50 100 150 200 250 300 350 400 450 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 10000
Capacity - USgpm
PERFORMANCE RANGE - 60 Hz, 3450 rpm
Capacity - m³/h 
20 30 40 50 60 70 80 90 100 200 300 400 500 600
600
500
400
N
NLS-01510 LS- NLS-0301002 100
300 010 NLS-02510 NLS-04010 90
NL 80
NLS-01508 S-04008 70
200 NLS-02008 NLS-02508 60
50
NLS-01506 NLS-03008
NLS-02506 40
100 30
90 NLS-02006 NLS-03006
80 NLS-01505
70
20
60
50
40
10
30
50 100 150 200 250 300 350 400 450 500 1000 1500 2000 2500 3000
Capacity - USgpm
Phone : +1-570-659-7200,  Email : [email protected]
Product Improvement and changes are a continuous process at ‘Northam’. The data given in this publication is therefore subject to revision.
Head - ft Head - ft
Head - m Head - m
01
2
-12S
NL
10
80
S-
0
NL