GC Horizontal Multistage Boiler Feed Pump High Pressure

GC Horizontal Multistage Boiler Feed Pump High Pressure

GC Horizontal Multistage Boiler Feed Pump | Segmental multistage design for high-pressure feedwater duty

  • Boiler feed / hot-water duty: For boiler make-up and high-pressure clean-water transfer.
  • Segmental multistage build: Stage configuration to match required system pressure with stable output.
  • Axial-thrust balancing: Balance device reduces axial load for continuous-duty stability.
  • Service-ready construction: Replaceable wear parts with clear maintenance access.
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Product Overview 

The GC Horizontal Boiler Feed Multistage Centrifugal Pump is a new type of horizontal, single-suction, multistage centrifugal pump designed primarily for boiler feed applications. It is suitable for transporting clean water and other non-corrosive liquids with similar physical and chemical properties to water at temperatures up to 110°C.

This pump series is widely used in industrial and mining enterprises, public facilities, and municipal household water supply systems, particularly for boiler feed systems.

Model Designation

GC Horizontal Multistage Boiler Feed Pump High Pressure

Key Features

  • Multi-stage sectional design, allows for adjusting the head by adding or removing stages to meet different operational requirements.

  • Precise alignment of the impeller and diffuser ensures stable flow, head, and efficiency.

  • Balanced impellers during the manufacturing process minimize vibration.

  • Axial thrust is balanced by a balancing disc and balancing ring assembly for stable operation.

  • Cast iron sealing rings reduce internal leakage, improving efficiency.

  • Durable shaft and bearing configuration ensure long service life.

  • Simple structure, with clear wear parts for easy maintenance.

Engineering Summary 

The GC pump adopts a multi-stage sectional structure. For models from 1-1/2GC to 4GC, the inlet and discharge nozzles are arranged vertically upward on the suction sleeve and discharge casing, respectively. The pump head can be adjusted by adding or removing stages to meet varying operational conditions.

Pump performance is highly dependent on assembly precision, especially the alignment between each impeller outlet and the corresponding diffuser inlet. Precise concentric alignment is crucial, as even slight misalignment can reduce flow, head, and efficiency. Reassembly requires careful inspection and adjustment.

Typical Applications 

  • Boiler feed systems

  • Pressure vessel water supply

  • Hot water circulation systems

  • High-rise building water supply

  • Agricultural irrigation

  • Firefighting pressure enhancement

  • Hydraulic washing systems

  • Food processing, brewing, pharmaceutical, and chemical industries

  • Aquaculture, environmental protection, chemical processing systems

  • Mechanical support systems for water supply and drainage

System Configuration 

The GC system primarily consists of the following core components:

  • Pump shaft and shaft sleeve

  • Suction sleeve

  • Driver

  • Discharge diffuser

  • Middle casing

  • Discharge casing

  • Sealing rings

  • Balancing ring and balancing disc assembly

  • End cover

  • Bearings: Single-row deep groove ball bearings, lubricated with calcium-based grease

  • Packing seal assembly: Includes stuffing box, gland, lantern ring, and packing

Components and Supply 

GC system components include:

  • Pump body, bearing assembly

  • Mechanical seal and shaft support system

  • Electric motor and drive system

  • Pipe fittings and installation accessories

Technical Service

The GC pump system provides comprehensive technical support and services, including installation and commissioning, operational monitoring, and maintenance recommendations. We provide detailed operation manuals, installation instructions, and remote technical support.

Operating Conditions 

  • Pumped medium: Clean water or non-corrosive liquids with similar properties to water.

  • Maximum liquid temperature: ≤110°C

  • Ambient temperature: ≤40°C

  • Bearing lubricants: Calcium-based grease

  • Suitable for continuous operation in boiler feed and pressurization systems.

Service Conditions

  • Fire hydrant system: Water gun flow rate of 2.5L/S, 5L/S, with jet lengths of 7m, 10m, and 13m.

  • Automatic sprinkler system: Flow rate of 1.0L/S per nozzle, with a nozzle pressure of 0.1MPa.

  • The environment temperature of the device: 5°C to 40°C.

Protection Functions 

The GC system is equipped with various protection functions, including overload protection, overpressure protection, and mechanical fault detection, ensuring safe and stable operation of the pump system under various extreme conditions.

Selection Criteria

The selection of the GC pump should be based on the specific application scenario, required flow rate, and head requirements. Consideration should also be given to installation space, ease of maintenance, and long-term system stability.

Installation & Dimensions

Outline Drawing

GC Horizontal Multistage Boiler Feed Pump High Pressure

Performance Data

1 Shaft Sleeve Nut 2 Bearing Cover 3 Bearing 4 Front Bearing Housing 5 Shaft Sleeve (A) 6 Packing Gland 7 Lantern Ring
8 Wear Ring 9 Suction Casing 10 Impeller 11 Middle Casing 12 Return Pipe 13 Discharge Casing 14 Balance Ring
15 Balance Disc 16 Tail Cover 17 Shaft Sleeve (B) 18 Shaft 19 Round Nut 20 Tension Bolt

Performance Parameters

Model Stages Flow Rate Q Total Head H Speed n Power N (kW) Efficiency η NPSH Impeller Diameter Weight
m3/h L/S m r/min Shaft Power Motor Power (kW) % m mm Kg
11/2GC-5 2 6 1.66 46 2950 2 3 38 3.7 136 135
11/2GC-5 3 6 1.66 69 2920 3 4 38 3.7 136 147
11/2GC-5 4 6 1.66 92 2920 4 5.5 38 3.7 136 174
11/2GC-5 5 6 1.66 115 2920 5 7.5 38 3.7 136 204
11/2GC-5 6 6 1.66 138 2920 6 7.5 38 3.7 136 212
11/2GC-5 7 6 1.66 161 2920 7 7.5 38 3.7 136 220
11/2GC-5 8 6 1.66 184 2920 8 11 38 3.7 136 271
11/2GC-5 9 6 1.66 207 2920 9 15 38 3.7 136 292
Model Stages Flow Rate Q Total Head H Speed n Power N (kW) Efficiency η NPSH Impeller Diameter Weight
m3/h L/S m r/min Shaft Power Motor Power (kW) % m mm Kg
2GC-5 2 10 2.8 64 2950 4.4 7.5 39.6 4.7 166 258
2GC-5 3 10 2.8 96 2950 6.6 11 39.6 4.7 166 309
2GC-5 4 10 2.8 128 2950 8.8 15 39.6 4.7 166 389
2GC-5 5 10 2.8 160 2950 11.0 15 39.6 4.7 166 414
2GC-5 6 10 2.8 192 2950 13.2 18.5 39.6 4.7 166 512
2GC-5 7 10 2.8 224 2950 15.4 22.0 39.6 4.7 166 531
2GC-5 8 10 2.8 256 2950 17.6 30.0 39.6 4.7 166 589
2GC-5 9 10 2.8 288 2950 19.8 30.0 39.6 4.7 166 609
Model Stages Flow Rate Q Total Head H Speed n Power N (kW) Efficiency η NPSH Impeller Diameter Weight
m3/h L/S m r/min Shaft Power Motor Power (kW) % m mm Kg
21/2GC-3.5 7
10
15
20
2.8
4.2
5.6
336
315
280
 2950
26
28.6
32.5
 37
35
45
47
3.3
3.8
4
 198 967
21/2GC-3.5 8
10
15
20
2.8
4.2
5.6
384
360
320
 2950
30
32.8
37
 45
35
45
47
3.3
3.8
4
 198 1065
21/2GC-3.5 9
10
15
20
2.8
4.2
5.6
432
405
360
 2950
33.7
37
42
 55
35
45
47
3.3
3.8
4
 198 1097
21/2GC-3.5 10
10
15
20
2.8
4.2
5.6
480
450
400
 2950
37.5
41
46.5
 55
35
45
47
3.3
3.8
4
 198 1179
21/2GC-3.5 11
10
15
20
2.8
4.2
5.6
528
495
440
 2950
41.5
45
51
 75
35
45
47
3.3
3.8
4
 198 1252
21/2GC-3.5 12
10
15
20
2.8
4.2
5.6
576
540
480
 2950
45
49
56
 75
35
45
47
3.3
3.8
4
 198 1324
Model Stages Flow Rate Q Total Head H Speed n Power N (kW) Efficiency η NPSH Impeller Diameter Weight
m3/h L/S m r/min Shaft Power Motor Power (kW) % m mm Kg
21/2GC-6 2
15
20
4.2
5.6
62
54
 2950
5.8
6.2
 7.5
43.7
47.4
5
5.3
 168 258
21/2GC-6 3
15
20
4.2
5.6
93
81
 2950
8.7
9.3
 15
43.7
47.4
5
5.3
 168 309
21/2GC-6 4
15
20
4.2
5.6
124
108
 2950
11.6
12.4
 18.5
43.7
47.4
5
5.3
 168 389
21/2GC-6 5
15
20
4.2
5.6
155
135
 2950
14.5
15.5
 22.0
43.7
47.4
5
5.3
 168 494
21/2GC-6 6
15
20
4.2
5.6
186
162
 2950
17.4
18.6
 22.0
43.7
47.4
5
5.3
 168 512
21/2GC-6 7
15
20
4.2
5.6
217
189
 2950
20.2
21.7
 30.0
43.7
47.4
5
5.3
 168 563
21/2GC-6 8
15
20
4.2
5.6
248
216
 2950
23.2
24.8
 30.0
43.7
47.4
5
5.3
 168 589
21/2GC-6 9
15
20
4.2
5.6
279
243
 2950
26.1
27.9
 37.0
43.7
47.4
5
5.3
 168 785
Model Stages Flow Rate Q Total Head H Speed n Power N (kW) Efficiency η NPSH Impeller Diameter Weight
m3/h L/S m r/min Shaft Power Motor Power (kW) % m mm Kg
4GC-8 2
30
45
55
8.3
12.5
15.3
86
82
79
 2950
13.8
16.8
18.1
 22
51
60
62.5
4.6
5
5.6
 192 503
4GC-8 3
30
45
55
8.3
12.5
15.3
129
123
114
 2950
20.7
25.2
27.2
 30
51
60
62.5
4.6
5
5.6
 192 612
4GC-8 4
30
45
55
8.3
12.5
15.3
172
164
152
 2950
27.6
33.6
35.2
 45
51
60
62.5
4.6
5
5.6
 192 835
4GC-8 5
30
45
55
8.3
12.5
15.3
215
205
190
 2950
34.5
42
45.3
 55
51
60
62.5
4.6
5
5.6
 192 950
4GC-8 6
30
45
55
8.3
12.5
15.3
258
246
228
 2950
41.4
50.4
54.4
 55
51
60
62.5
4.6
5
5.6
 192 1085
4GC-8 7
30
45
55
8.3
12.5
15.3
301
287
266
 2950
48.3
58.8
63.4
 75
51
60
62.5
4.6
5
5.6
 192 1087
4GC-8 8
30
45
55
8.3
12.5
15.3
344
328
304
 2950
55
67
73
 75
51
60
62.5
4.6
5
5.6
 192
4GC-8 9
30
45
55
8.3
12.5
15.3
387
369
342
 2950
62
75.5
82
 90
51
60
62.5
4.6
5
5.6
 192
4GC-8 10
30
45
55
8.3
12.5
15.3
430
410
380
 2950
69
84
91
 100
51
60
62.5
4.6
5
5.6
 192

Installation Diagram

GC Horizontal Multistage Boiler Feed Pump High Pressure

Performance Data（2）

Model Number of Stages A B C E H I J K L M N O P Q F n-φd
11/2GC-5 2 963 750 510 128 248 122.5 355 350 205 365 105 180 315 315 154 4-φ20
11/2GC-5 3 1033 805 535 125 248 172.5 355 358 205 405 115 190 355 355 154 4-φ20
11/2GC-5 4 1158 1010 715 135 248 222.5 360 393 205 415 135 210 365 365 47 4-φ20
11/2GC-5 5 1208 1010 715 135 248 272.5 360 393 205 415 135 210 365 365 97 4-φ20
11/2GC-5 6 1258 1010 715 135 248 322.5 360 393 205 415 135 210 365 365 147 4-φ20
11/2GC-5 7
1308
1433
1060
1180
715
760
135
170
 248 372.5 360
393
495
 205
415
470
135
163
210
255
 365
365
240
147
100
 4-φ20
11/2GC-5 8 1484 1280 785 170 248 422.5 395 470 205 470 165 255 365 420 95 4-φ20
11/2GC-5 9 1533 1280 785 170 248 472.5 395 470 205 470 165 255 365 420 145 4-φ20
Model Number of Stages A B C E H I J K L M N O P Q F n-φd
2GC-5 2 1227 915 650 135 325 160 480 443 255 490 135 210 430 430 211 4-φ24
2GC-5 3 1412 1160 790 165 325 220 485 490 255 480 165 255 430 430 141 4-φ24
2GC-5 4 1412 1160 790 165 325 280 485 490 255 480 165 255 430 430 201 4-φ24
2GC-5 5 1532 1220 820 165 325 340 485 490 255 480 165 255 430 430 201 4-φ24
2GC-5 6 1637 1320 860 185 325 400 485 490 255 480 165 255 430 430 203 4-φ24
2GC-5 7 1722 1380 900 200 325 460 480 510 255 515 180 285 455 455 209 4-φ24
2GC-5 8 1887 1575 1000 240 325 520 525 580 255 585 200 310 440 525 150 4-φ24
2GC-5 9 1947 1575 1000 240 325 580 525 580 255 585 200 310 440 525 210 4-φ24
Model Number of Stages A B C E H I J K L M N O P Q F n-φd
21/2GC-3.5 7 1937 1590 1030 225 385 470 608 598 295 600 200 310 540 540 195 4-φ24
21/2GC-3.5 8 1937 1675 1085 225 385 530 618 638 295 600 225 345 540 540 194 4-φ24
21/2GC-3.5 9 2212 1835 1170 265 385 590 643 683 295 600 250 385 540 610 192 4-φ24
21/2GC-3.5 10 2272 1895 1200 265 385 650 643 683 295 600 250 385 540 610 192 4-φ24
21/2GC-3.5 11 2402 2115 1280 320 385 710 675 750 295 715 280 410 530 655 131 4-φ24
21/2GC-3.5 12 2462 2115 1280 320 385 770 675 750 295 715 280 410 530 655 191 4-φ24
型号 Number of Stages A B C E H I J K L M N O P Q F n-φd
21/2GC-6 2 1227 915 650 135 325 160 480 443 255 490 135 210 430 430 211 4-φ24
21/2GC-6 3 1412 1160 790 165 325 220 485 490 255 480 165 255 430 430 141 4-φ24
21/2GC-6 4 1412 1160 790 165 325 280 485 490 255 480 165 255 430 430 201 4-φ24
21/2GC-6 5 1577 1320 860 185 325 340 485 490 255 480 165 255 430 430 143 4-φ24
21/2GC-6 6 1662 1380 900 200 325 400 480 510 255 515 180 285 455 455 149 4-φ24
21/2GC-6 7 1827 1575 1000 240 325 460 525 580 255 585 200 310 440 525 90 4-φ24
21/2GC-6 8 1887 1575 1000 240 325 520 525 580 255 585 200 310 440 525 150 4-φ24
21/2GC-6 9 1947 1575 1000 240 325 525 525 580 255 585 200 310 440 525 210 4-φ24
Model Number of Stages A B C E H I J K L M N O P Q F n-φd
4GC-8 2 1552 1230 845 190 385 190 610 575 295 600 180 285 540 480 185 4-φ24
4GC-8 3 1732 1385 925 225 385 265 610 600 295 600 200 310 540 540 185 4-φ24
4GC-8 4 1847 1485 980 235 385 340 620 640 295 600 225 345 540 540 184 4-φ24
4GC-8 5 2037 1735 1105 265 385 415 645 685 295 665 250 385 540 605 117.5 4-φ24
4GC-8 6 2112 1735 1105 265 385 490 645 685 295 665 250 385 540 605 192.5 4-φ24
4GC-8 7 2257 1955 1215 300 385 565 675 750 295 720 280 410 540 660 116.5 4-φ24
4GC-8 8 2332 1955 1215 300 385 640 675 750 295 720 280 410 540 660 191.5 4-φ24
4GC-8 9 2457 2080 1295 325 385 715 675 750 295 720 280 410 540 660 191.5 4-φ24

Outline Drawing（2）

GC Horizontal Multistage Boiler Feed Pump High Pressure

Performance Data（2）

Dimension Suction Flange
Model Dg Do D n–do
11/2GC-5 40 115 145 4-φ18
2GC-5 50 125 160 4-φ18
21/2GC-6 65 145 180 8-φ18

Pump Installation & Performance

Pump Head H Calculation:
GC Horizontal Multistage Boiler Feed Pump High Pressure

Pump Head and Installation Calculations:

In the formula:

  • P1: Suction pressure (MPa)

  • P2: Discharge pressure (MPa)

  • Z1: Vertical distance from the suction pressure gauge to the pump shaft center (m)

  • Z2: Vertical distance from the discharge pressure gauge to the pump shaft center (m)

  • V1: Flow velocity at the suction point (m/s)

  • V2: Flow velocity at the discharge measuring point (m/s)

  • ρ: Liquid density (kg/m³)

  • g: Gravitational acceleration (9.8 m/s²)

Pump Installation Height (Mercury Alloy Calculation):
(Installation height refers to the vertical distance from the pump shaft centerline to the liquid level)
High point ≤ P0 – [NPSH] – P’ – △h – 0.5(m)

In the formula:

  • P0: Atmospheric pressure (or absolute pressure at the liquid surface) (water column unit)

  • [NPSH]: Net Positive Suction Head required by the pump (m)

  • P’: Vapor pressure of the pumped liquid (m water column)

  • △h: Hydraulic head loss (m)

Note:
When the pump shaft center is above the liquid level, the pump is positive (indicating suction mode).
When the value is negative, the pump is in submerged suction mode (indicating the pump is submerged in liquid).

The pump’s flow rate (Q), head (H), and shaft power (N) are related to the actual pump speed.

Calculation formula:
GC Horizontal Multistage Boiler Feed Pump High Pressure

Operating Manual

Assembly and Disassembly

(I) Pump Disassembly Instructions

  1. Follow the shutdown sequence to stop the pump.

  2. Drain the liquid from the pump casing (including cooling water). If the bearings use oil lubrication, drain the oil as well.

  3. Remove any auxiliary pipelines obstructing disassembly, such as balancing pipes, sealing water pipes, and electrical wires.

  4. During disassembly, strictly protect the processing precision of all components. When removing the tie rod, use blocks to support the middle of the band tube to prevent the connecting joint from loosening or sinking, which could potentially bend the pump shaft.

(II) Pump Disassembly Sequence

  1. Remove the bolts on the bearing end cover of the discharge side and the connecting bolts between the discharge casing, tail cover, and bearing casing. Remove the bearing end cover and bearing casing components.

  2. Remove the circular nut on the shaft, then take out the inner bearing ring, bearing gland, and retaining ring. Disassemble the packing box assembly (including packing gland, lantern ring, and packing).

  3. Remove the O-ring, shaft sleeve, balance disk, and key from the shaft. Then, remove the discharge sleeve, upper diffuser half, balance ring, and sleeve.

  4. Remove the final impeller and key, then take out the middle casing and diffuser. Continue removing impellers, mid casings, and diffusers in stages until the first stage impeller is removed.

  5. Remove the pump joint, then remove the connecting nuts between the suction casing and bearing casing and disassemble the bearing casing on the suction side.

  6. Pull the shaft from the suction tube surface, remove the shaft nut, and take out the inner bearing ring, O-ring, shaft sleeve, etc.

  7. For pumps with sleeve bearings, the operation method is similar, but the procedure for removing bearing components may differ slightly.

(III) Pump Assembly

Assembly is usually carried out in reverse order of disassembly. The quality of assembly directly affects the pump’s performance, service life, and reliability.

Key Points:

  1. Protect the processing precision and surface smoothness of the components. Avoid scratches or dents. Molybdenum disulfide used for sealing must remain clean. All bolts and screws should be tightened to the correct torque.

  2. Ensure proper axial dimensioning of each component to align the impeller outlet channel with the corresponding diffuser inlet channel. Misalignment can affect pump performance. The pump dimensions should not be altered at will.

  3. After assembly and before installing packing, manually rotate the rotor to check if it rotates smoothly, and confirm that axial end movement is within tolerance.

  4. After inspection, install the packing and ensure the lantern ring is correctly aligned in the packing chamber.

Preparation Work

(I) Startup Preparation

  1. Rotate the pump rotor by hand before startup to ensure it rotates freely.

  2. Confirm that the motor’s rotation direction matches the pump’s rotation direction.

  3. Open the inlet valve, close the discharge valve, and the pressure gauge bracket to ensure the pump is fully primed, or use a vacuum system to evacuate air from the suction pipe and pump casing.

  4. Check the tightness of the bolts connecting the pump and motor, and ensure the surrounding area is safe. The pump must be fully prepared for operation.

  5. Power on the motor. After the pump reaches a stable speed, open the pressure gauge hole and gradually open the discharge valve until the pressure gauge indicates the desired discharge pressure (which corresponds to the required pump head).

(II) Operation

The pump series employs a balancing mechanism to offset axial thrust. Balanced water flows back into the suction pipe through a balancing pipe or via an external short pipe. The balancing water pipe must never be clogged.
2) During startup and operation, monitor instrument readings, bearing temperatures, packing leakage, pump vibration, and noise. Immediately address any abnormal conditions.
3) A rise in bearing temperature reflects assembly quality. The temperature increase in bearings should not exceed 35°C above ambient temperature. The maximum bearing temperature should not exceed 75°C.
4) The pump rotor will have a certain amount of axial float during operation. The axial shift must remain within the allowable range. Maintain proper clearance between the motor and pump coupling.
5) Periodically check components such as the impeller, wear rings, lantern rings, shaft sleeves, and balance discs for wear. Replace parts when significant wear occurs.

(III) Shutdown

  1. Before stopping, close the discharge valve gradually, and then cut off the power supply to the motor. After the pump has completely stopped, close the inlet valve.

  2. Drain the liquid from the pump. For long-term shutdown, disassemble, clean, lubricate, and properly store the pump.

OEM & Custom

We provide OEM/ODM manufacturing with customizable materials (cast iron, stainless steel, alloy steel), voltages (220V/415V/460V), and control systems. Options include explosion-proof motors, extended shafts, and flange customization (DIN/ANSI/JIS). Each pump is hydraulically tested to meet ISO9001 and CE standards for global markets.

FAQs

  1. Q: What is the main application of GC multistage pumps?
    A: Mainly used for boiler feed, pressure boosting, and clean water supply in industrial and municipal systems.
  2. Q: What is the maximum temperature the pump can handle?
    A: Up to 110°C for clean or slightly hot water applications.
  3. Q: What materials are available?
    A: Standard cast iron; optional stainless steel or alloy for specific industrial fluids.
  4. Q: What is the maximum head and flow range?
    A: Head up to 400 meters; flow rate 6–55 m³/h depending on model and stage number.
  5. Q: What kind of seal is used?
    A: Standard packing seal; mechanical seals available for optional configurations.
  6. Q: How should the pump be maintained?
    A: Regular lubrication, seal inspection, and yearly performance checks are recommended.
  7. Q: Which industries use GC pumps?
    A: Power plants, manufacturing, chemical processing, HVAC, and water supply projects globally.