D/DG Horizontal Multistage Centrifugal Pump for Clean Water

D/DG Horizontal Multistage Centrifugal Pump for Clean Water

D/DG Horizontal Multistage Boiler Feed Pump | Segmental multistage design for high-pressure feedwater duty

  • High-pressure feedwater duty: Boiler feed and high-pressure transfer.
  • High-efficiency hydraulics: Optimized for efficient, stable performance.
  • Axial-thrust balancing: Balance disc design controls axial load for stable continuous duty.
  • Sealing & service friendly: Packing or mechanical seal; full shaft protection; easy maintenance.

Product Overview

D / DG Horizontal Multistage Boiler Feed Pump is a horizontal, single-suction, segmented multistage centrifugal pump designed for high-pressure clean water and boiler feed systems.

It provides staged pressure build-up for continuous high-head water supply under industrial operating conditions.

It is suitable for boiler feedwater systems, mine drainage, high-rise building pressurization, and industrial clean water transfer.

✔ For detailed hydraulic data and configuration guidance, refer to the technical section below.

Model Designation

DDG Horizontal Multistage Centrifugal Pumptype 2

Applications

  • Boiler feed systems under medium and high-pressure steam operation
  • Mine drainage requiring multi-stage pressure lifting
  • High-rise building secondary water supply systems
  • Industrial high-head clean water transfer pipelines
  • Pressure boosting systems for municipal water distribution

Engineering Advantages

  • Segmented casing structure allows head adjustment by varying stage number
  • Cast iron impellers with static balancing reduce hydraulic pulsation
  • Balancing disc assembly controls axial thrust under high-pressure conditions
  • Replaceable seal rings and shaft sleeves extend maintenance cycle
✔ The D/DG series integrates multistage hydraulic design with axial thrust balancing mechanism to ensure stable high-pressure continuous-duty performance.

System Components

The D / DG Horizontal Multistage Boiler Feed Pump mainly consists of:

  • Pump shaft
  • Impeller assembly
  • Diffuser / guide vane
  • Suction section(
  • Intermediate section
  • Discharge section
  • Balancing disc & balancing ring
  • Shaft sleeve
  • Seal ring
  • Bearing housing & bearings

Technical Specifications

Service Conditions

  • Indoor installation recommended
  • Ambient temperature ≤ 40°C
  • Relative humidity ≤ 95%
  • Stable foundation required to minimize vibration transmission

Operating Conditions

  • Medium: Clean water or non-corrosive liquid without solid particles
  • D type maximum temperature: ≤ 80°C
  • DG type maximum temperature: ≤ 110°C
  • Rotation direction: Clockwise when viewed from motor side

Performance Range

  • Flow rate: 6.3 – 450 m³/h
  • Head: 50 – 650 m
  • Power range: 2.2 – 400 kW
  • Speed: 1450 / 2900 rpm
  • Liquid temperature: ≤ 80°C (D) / ≤ 110°C (DG)
  • Working pressure: ≤ 6.0 MPa

Detailed parameter tables are provided below.

Installation & Dimensions

Outline Drawing

DDG Horizontal Multistage Centrifugal Pumptypeshiyitu

Performance Data

1
Suction Section
2
Discharge Section
3
Middle Section
4
Diffuser
5
Impeller
6
Tail Cover
7
Seal Ring
8
Diffuser Sleeve
9
Balance Ring
10
Balance Disc
11
Packing Ring
12
Shaft
13
Shaft Sleeve A
14
Shaft Sleeve B
15
Left Bearing Assembly
16
Right Bearing Assembly
17
Bearing Collar
18
Tie Bolt
19
Packing Gland

Performance Parameters

Model
Rotational Speed
Flow Rate
Head
Efficiency
Power (kW)
NPSHr
(r/min)
(m3/h)
(L/s)
(m)
(%)
Shaft Power
Motor Power
(m)
DG6-25×3
2950
6.3
1.75
75
45
2.86
5.5
2
DG6-25×4
2950
6.3
1.75
100
45
3.81
7.5
2
DG6-25×5
2950
6.3
1.75
125
45
4.77
7.5
2
DG6-25×6
2950
6.3
1.75
150
45
5.72
11
2
DG6-25×7
2950
6.3
1.75
175
45
6.67
11
2
DG6-25×8
2950
6.3
1.75
200
45
7.63
15
2
DG6-25×9
2950
6.3
1.75
225
45
8.52
15
2
DG6-25×10
2950
6.3
1.75
250
45
9.53
18.5
2
DG6-25×11
2950
6.3
1.75
275
45
10.5
18.5
2
DG6-25×12
2950
6.3
1.75
300
45
11.44
18.5
2
Model
Rotational Speed
Flow Rate
Head
Efficiency
Power (kW)
NPSHr
(r/min)
(m3/h)
(L/s)
(m)
(%)
Shaft Power
Motor Power
(m)
DG12-25×3
2950
12.5
3.47
75
54
4.73
7.5
2
DG12-25×4
2950
12.5
3.47
100
54
6.3
11
2
DG12-25×5
2950
12.5
3.47
125
54
7.88
11
2
DG12-25×6
2950
12.5
3.47
150
54
9.46
15
2
DG12-25×7
2950
12.5
3.47
175
54
11
15
2
DG12-25×8
2950
12.5
3.47
200
54
12.51
18.5
2
DG12-25×9
2950
12.5
3.47
225
54
14.18
18.5
2
DG12-25×10
2950
12.5
3.47
250
54
15.76
22
2
DG12-25×11
2950
12.5
3.47
275
54
17.34
22
2
DG12-25×12
2950
12.5
3.47
300
54
18.9
30
2
Model
Rotational Speed
Flow Rate
Head
Efficiency
Power (kW)
NPSHr
(r/min)
(m3/h)
(L/s)
(m)
(%)
Shaft Power
Motor Power
(m)
DG25-30×3
2950
25
6.94
90
62
9.88
15
2
DG25-30×4
2950
25
6.94
120
62
13.1
18.5
2
DG25-30×5
2950
25
6.94
150
62
16.47
22
2
DG25-30×6
2950
25
6.94
180
62
19.77
30
2
DG25-30×7
2950
25
6.94
210
62
23.1
30
2
DG25-30×8
2950
25
6.94
240
62
26.4
37
2
DG25-30×9
2950
25
6.94
270
62
29.65
37
2
DG25-30×10
2950
25
6.94
300
62
32.9
4.5
2
Model
Rotational Speed
Flow Rate
Head
Efficiency
Power (kW)
NPSHr
(r/min)
(m3/h)
(L/s)
(m)
(%)
Shaft Power
Motor Power
(m)
DG46-30×3
2950
46
12.8
90
70
16.11
22
3
DG46-30×4
2950
46
12.8
120
70
21.48
30
3
DG46-30×5
2950
46
12.8
150
70
26.85
37
3
DG46-30×6
2950
46
12.8
180
70
32.21
37
3
DG46-30×7
2950
46
12.8
210
70
37.58
45
3
DG46-30×8
2950
46
12.8
240
70
42.95
55
3
DG46-30×9
2950
46
12.8
270
70
48.32
55
3
DG46-30×10
2950
46
12.8
300
70
53.69
75
3
Model
Rotational Speed
Flow Rate
Head
Efficiency
Power (kW)
NPSHr
(r/min)
(m3/h)
(L/s)
(m)
(%)
Shaft Power
Motor Power
(m)
DG46-50×3
2950
46
12.8
150
63
29.83
37
3
DG46-50×4
2950
46
12.8
200
63
39.77
45
3
DG46-50×5
2950
46
12.8
250
63
49.71
55
2.8
DG46-50×6
2950
46
12.8
300
63
59.65
75
2.8
DG46-50×7
2950
46
12.8
350
63
69.6
90
2.8
DG46-50×8
2950
46
12.8
400
63
79.54
90
2.8
DG46-50×9
2950
46
12.8
450
63
89.48
110
2.8
DG46-50×10
2950
46
12.8
500
63
99.42
110
2.8
DG46-50×11
2950
46
12.8
550
63
109.36
132
2.8
DG46-50×12
2950
46
12.8
600
63
119.3
132
2.8

Installation Diagram

DDG Horizontal Multistage Centrifugal Pumptypeanzhuang 6

Performance Data

Model
A
B
C
E
F
L
I
M
N
O
H
J
b
K
P
Q
n-φd
DG6-25×3
1175
885
600
145
192
250
180
265
135
210
230
440
170
413
390
390
4-φ24
DG6-25×4
1225
985
650
195
142
250
230
265
135
210
230
400
170
413
390
390
4-φ24
DG6-25×5
1275
985
650
195
192
250
280
265
135
210
230
400
170
413
390
390
4-φ24
DG6-25×6
1450
1205
785
245
141
250
330
265
165
255
240
410
170
465
435
435
4-φ24
DG6-25×7
1500
1205
785
245
191
250
380
265
165
255
240
410
170
465
435
435
4-φ24
DG6-25×8
1550
1305
835
295
141
250
430
265
165
255
240
410
170
465
435
435
4-φ24
DG6-25×9
1600
1305
835
295
191
250
480
265
165
255
240
410
170
465
435
435
4-φ24
DG6-25×10
1695
1500
935
370
91
250
530
265
165
255
240
410
170
465
435
435
4-φ24
DG6-25×11
1745
1500
935
370
141
250
580
265
165
255
240
410
170
465
435
435
4-φ24
DG6-25×12
1795
1500
935
370
191
250
630
265
165
255
240
410
170
465
435
435
4-φ24
Model
A
B
C
E
F
L
I
M
N
O
H
J
b
K
P
Q
n-φd
DG12-25×3
1175
874
600
140
180
250
180
265
135
210
230
400
170
413
395
295
4-φ25
DG12-25×4
1350
1040
710
165
183
250
230
265
165
255
240
410
170
465
430
430
4-φ25
DG12-25×5
1400
1090
730
190
183
250
280
265
165
255
240
410
170
465
430
430
4-φ25
DG12-25×6
1450
1140
740
232
183
250
330
265
165
255
240
410
170
465
430
430
4-φ25
DG12-25×7
1500
1190
780
242
183
250
380
265
165
255
240
410
170
465
430
430
4-φ25
DG12-25×8
1595
1284
830
266
183
250
430
265
165
255
240
410
170
465
430
430
4-φ25
DG12-25×9
1645
1334
850
294
183
250
840
265
165
255
240
410
170
465
430
430
4-φ25
DG12-25×10
1720
1397
870
327
172
250
530
265
180
285
260
430
170
510
400
460
4-φ25
DG12-25×11
1770
1447
900
347
172
250
580
265
180
285
260
430
170
510
400
460
4-φ25
DG12-25×12
1925
1571
980
371
176
250
633
265
200
310
260
450
170
555
400
500
4-φ25
Model
A
B
C
E
F
L
I
M
N
O
H
J
b
K
P
Q
n-φd
DG25-30×3
1450
1110
760
185
227
285
230
330
165
255
250
460
210
475
460
460
4-φ30
DG25-30×4
1560
1219
850
204
228
285
295
330
165
255
250
460
210
475
460
460
4-φ30
DG25-30×5
1650
1297
880
237
228
285
360
330
180
285
260
470
210
510
460
460
4-φ30
DG25-30×6
1825
1432
970
262
225
285
425
330
200
310
280
490
210
555
460
505
4-φ30
DG25-30×7
1885
1497
1000
297
225
285
490
330
200
310
280
490
210
555
460
505
4-φ30
DG25-30×8
1950
1562
1030
332
225
285
555
330
200
310
280
490
210
555
460
505
4-φ30
DG25-30×9
2015
1627
1080
347
225
285
620
330
200
310
280
490
210
555
460
505
4-φ30
DG25-30×10
2150
1728
1120
398
222
285
685
330
225
345
305
515
210
610
540
460
4-φ30
Model
A
B
C
E
F
L
I
M
N
O
H
J
b
K
P
Q
n-φd
DG46-30×3
1520
1167
845
130
228
285
230
330
180
285
260
470
210
510
460
460
4-φ30
DG46-30×4
1690
1302
850
242
225
285
295
330
200
310
280
490
210
555
460
505
4-φ30
DG46-30×5
1755
1367
910
247
225
285
360
330
200
310
280
490
210
555
460
505
4-φ30
DG46-30×6
1820
1432
935
287
225
285
425
330
200
310
280
490
210
555
460
505
4-φ30
DG46-30×7
1925
1532
1010
302
223
285
490
330
225
345
305
515
210
610
460
545
4-φ30
DG46-30×8
2105
1694
1110
349
221
285
555
330
250
385
330
540
210
655
460
594
4-φ30
DG46-30×9
2170
1759
1140
384
221
285
620
330
250
385
330
540
210
655
460
594
4-φ30
DG46-30×10
2305
1897
1245
402
219
285
685
330
280
410
360
570
210
720
460
650
4-φ30
Model
A
B
C
E
F
L
I
M
N
O
H
J
b
K
P
Q
n-φd
DG46-50×3
1717
1317
875
215
246
339
245
353
200
310
360
630
300
635
500
500
4-φ24
DG46-50×4
1817
1415
925
293
246
339
305
353
225
345
420
690
300
725
500
500
4-φ24
DG46-50×5
1992
1571
1020
341
240
339
365
353
250
385
420
690
300
745
500
600
4-φ24
DG46-50×6
2122
1758
1130
321
180
339
425
353
280
410
420
690
300
780
500
650
6-φ24
DG46-50×7
2182
1758
1130
321
240
339
485
353
280
410
420
690
300
780
500
650
6-φ24
DG46-50×8
2292
1869
1180
331
240
339
545
353
280
410
420
690
300
780
500
650
6-φ24
DG46-50×9
2473
2046
1330
360
166
339
605
353
323
550
515
785
300
970
500
750
6-φ24
DG46-50×10
2533
2046
1330
360
226
339
665
353
323
550
515
785
300
970
500
750
6-φ24
DG46-50×11
2641
2222
1480
370
166
339
725
353
323
550
515
785
300
970
500
750
6-φ24
DG46-50×12
2701
2222
1480
370
226
339
785
353
323
550
515
785
300
970
500
750
6-φ24

Outline Drawing(2)

7d71babb8917c159d21c88af5c3734c8

Installation Dimensions

Dimensions
Suction Flange
Discharge Flange
Model
Dg
Do
D
n-do
Dg
Do
D
n-do
D6-25
DG6-25
40
100
130
4-φ13.5
40
110
150
4-φ17.5
D12-25
DG12-25
50
110
140
4-φ13.5
40
110
150
4-φ17.5
D25-30
DG25-30
65
130
160
4-φ17.5
65
145
185
8-φ17.5
D46-30
DG46-30
80
150
190
4-φ17.5
65
145
185
8-φ17.5
D46-50
DG46-50
80
150
170
190
215
4-φ17.5
8-φ22
80
170
215
8-φ22

How to Select a Pump Model

  • Calculate required flow rate and total head based on system resistance and elevation
  • Select stage number ensuring duty point lies within high-efficiency operating range
  • Confirm medium temperature to distinguish D or DG configuration
  • Verify system pressure does not exceed allowable working pressure
  • Consider continuous-duty requirements and plan redundancy if required
✔ Pump model selection shall be based on calculated hydraulic duty point and pressure class to ensure structural and operational compatibility.

Engineering Notes

  • Balancing disc clearance must be maintained within design tolerance to ensure axial stability
  • Improper alignment between impeller and diffuser may reduce hydraulic efficiency
  • For high-temperature DG applications, thermal expansion effects must be considered
  • Long pipeline systems should include non-return valves to prevent reverse flow

Compliance & Quality Assurance

  • Hydraulic performance test conducted before shipment
  • Pressure casing hydrostatic testing
  • Impeller static balance verification
  • Bearing assembly clearance inspection
  • Material traceability for critical pressure components

Safety Notice

  • Do not operate under dry-running condition
  • Ensure suction system is fully primed before startup
  • Do not exceed rated discharge pressure
  • Disconnect power supply before maintenance

OEM & Customization

This pump series supports engineered configuration and duty-based matching. Technical adjustments can be made according to system requirements and installation conditions.

Available options include:

  • Motor voltage & frequency
  • Mechanical seal type and configuration
  • Wetted parts material selection
  • Surface coating and corrosion protection

Configuration is determined based on duty point and project specifications.

FAQs

Q: Can the pump operate under VFD control?
A: Yes, operation under variable frequency control is permitted within rated hydraulic limits.

Q: What is the maximum allowable working pressure?
A: The maximum allowable working pressure is 6.0 MPa.

Q: What seal options are available?
A: Mechanical seal and packing seal configurations are available.

Q: How is axial thrust controlled?
A: Axial thrust is absorbed through a balancing disc assembly.

Q: What rotational speeds are available?
A: Standard speeds are 1450 rpm and 2900 rpm.

Q: What type of liquid is permitted?
A: Clean water or non-corrosive liquids without solid particles.

Q: What is the allowable maximum liquid temperature?
A: D type ≤ 80°C; DG type ≤ 110°C.