Overview
The ISG series vertical in-line centrifugal pump is a single-stage, single-suction pipeline pump engineered for direct inline installation within piping systems. Its compact vertical design allows it to be mounted directly into a pipeline — much like a valve — eliminating the need for extensive foundation work or large installation footprints. Developed using optimized hydraulic models and conforming to JB/T design standards and ISO 2858 manufacturing specifications, the ISG series delivers reliable performance across water supply, HVAC circulation, industrial pressurization, and fire protection boost applications.
Based on the ISG platform, five derivative variants serve distinct medium and environmental requirements: the IRG for hot water circulation (up to 120°C), the IHG for corrosive chemical transfer, the YG for petroleum products, the IHGB in stainless steel for flammable chemical liquids, and the low-speed D-type for noise-sensitive environments such as air conditioning systems and office buildings.
Key Design Features
1. Inline Vertical Structure
The inlet and outlet share the same diameter and sit on a common centerline, enabling direct pipeline installation without additional transition piping. The compact footprint reduces building space requirements and allows outdoor installation when fitted with a protective cover.
2. Direct-Coupled Impeller and Motor
The impeller mounts directly onto the motor’s extended shaft, creating a short axial dimension and a tightly integrated structure. The bearing configuration effectively balances radial and axial loads generated during operation, resulting in smooth running with low vibration and reduced noise levels.
3. Mechanical Shaft Seal
The shaft seal employs a mechanical seal or mechanical seal combination, utilizing imported titanium alloy seal rings and medium-temperature resistant mechanical seals with hard alloy materials. This wear-resistant arrangement extends seal service life under continuous operation. Normal leakage during operation remains within 3 drops per minute.
4. Top Pull-Out Maintenance
Maintenance does not require dismantling the connected piping system. Simply remove the pump coupling base nuts to extract the complete rotor assembly for inspection or repair.
5. Series and Parallel Operation
Multiple ISG pumps can be configured in series or parallel arrangements to meet varying flow and head requirements, providing flexibility in system design.
6. Flexible Orientation
The pump can be installed in either vertical or horizontal orientation depending on pipeline routing requirements.
Technical Specifications
| Parameter | Value |
|---|---|
| Pump Type | Single-Stage Single-Suction Vertical In-Line Centrifugal Pump |
| Design Standard | JB/T design requirements, ISO 2858 |
| Max Suction Pressure | ≤ 1.0 MPa |
| Max System Working Pressure | ≤ 1.6 MPa (suction + head) |
| Static Pressure Test | 2.5 MPa |
| Max Ambient Temperature | < 40°C |
| Max Relative Humidity | < 95% |
| Max Solid Particle Content | ≤ 0.1% by volume, grain size < 0.2 mm |
| ISG Medium Temperature | < 80°C (clean water) |
| IRG Medium Temperature | < 120°C (hot water) |
| IHG Medium Temperature | -20°C to 120°C (corrosive liquids) |
| YG Medium Temperature | -20°C to 120°C (petroleum products) |
| Mechanical Seal Leakage | ≤ 3 drops/min |
| Max Bearing Temperature | ≤ 70°C |
| Inlet/Outlet | Same diameter, inline (e.g., 50 mm nominal) |
| Impeller Diameter | e.g., 160 mm nominal (trim options A, B available) |
Product Variants
| Model | Application | Medium |
|---|---|---|
| ISG | General water supply, HVAC, fire boost | Clean water and similar liquids |
| IRG | Hot water circulation, heating systems | Hot water up to 120°C |
| IHG | Chemical, petroleum, pharmaceutical | Corrosive, non-solid liquids |
| YG | Fuel transfer, oil systems | Gasoline, kerosene, diesel |
| IHGB | Flammable chemical handling | Flammable chemical liquids (stainless steel) |
| ISGD/IRGD/IHGD/YGD/IHGBD | Noise-sensitive environments | Same as base type, low-speed operation |
Installation Guidelines
Pre-Installation Checks
- Inspect all fasteners for tightness and verify the pump flow passage is free of debris before startup.
- Ensure piping weight is not supported by the pump body to prevent deformation.
- Secure anchor bolts firmly to minimize vibration impact during startup.
- Install isolation valves on both inlet and outlet piping, and mount a pressure gauge near the outlet for operational monitoring.
- Manually rotate the pump shaft to confirm no friction or binding exists in the impeller.
Connection Types
The pump supports both rigid and flexible connection installation methods, selected based on system vibration isolation requirements and piping configuration.
Startup Procedure
- Verify motor rotation direction — clockwise when viewed from the motor top. Keep test runs brief to avoid dry-running the mechanical seal.
- Open the vent valve and fill the pump body completely with liquid, then close the vent valve.
- Check all connections and mounting points.
- Manually turn the pump to distribute lubricant across the mechanical seal faces.
- For hot water models, preheat at a rate of 50°C per hour to ensure uniform thermal expansion.
- Open the inlet valve fully and close the discharge valve.
- Start the motor and verify correct operation.
- Gradually open the discharge valve to reach the desired operating point. Monitor motor current to ensure it stays within the rated value.
- Verify shaft seal leakage is within 3 drops per minute and bearing temperature does not exceed 70°C.
Shutdown Procedure
- For hot water models, cool down at a rate below 10°C per minute until temperature drops below 80°C.
- Close the discharge valve.
- Stop the motor.
- Close the inlet valve.
- For extended shutdown periods, drain all liquid from the pump.
Operation and Maintenance
Routine Monitoring
- Ensure the inlet piping remains fully primed — avoid running the pump in cavitation conditions.
- Monitor motor current regularly to confirm it does not exceed the rated value.
- After extended operation, increased noise or vibration may indicate wear on impellers or bearings. Schedule inspection and replace worn components as needed. Typical major overhaul interval is approximately one year.
Mechanical Seal Care
- Seal lubrication must remain clean and free of solid particles.
- Never operate the mechanical seal in dry-running conditions.
- Before each startup, manually rotate the pump several times to prevent sudden seal ring fracture.
- Seal leakage exceeding 3 drops per minute requires investigation.
Common Troubleshooting
| Issue | Possible Cause | Remedy |
|---|---|---|
| No flow at startup | Air trapped in pump body; inlet valve closed | Vent pump fully; open inlet valve |
| Excessive vibration | Loose anchor bolts; misaligned piping | Tighten bolts; relieve piping stress on pump |
| High motor current | Discharge valve too open; impeller binding | Throttle discharge valve; inspect impeller |
| Seal leakage exceeds 3 drops/min | Seal face wear; dry operation damage | Inspect and replace mechanical seal |
| Abnormal noise | Cavitation; bearing wear; impeller rubbing | Check NPSH; inspect bearings and clearances |
Application Scenarios
High-Rise Building Water Supply
ISG pumps are widely used for domestic water pressurization in residential and commercial buildings. Their inline design allows direct integration into vertical risers without requiring additional piping modifications, saving valuable mechanical room space.
HVAC Circulation Systems
In heating, ventilation, and air conditioning systems, the ISG (and its low-speed D-type variant) circulates chilled or hot water through fan coil units, air handling units, and radiant heating networks. The compact inline footprint fits neatly into equipment rooms and pipe shafts.
Industrial Process Water
For manufacturing facilities requiring reliable process water transfer, the IHG chemical variant handles mildly corrosive media in textile, paper, food processing, and pharmaceutical applications. The stainless steel IHGB variant serves environments handling flammable chemical liquids.
Fire Protection Water Boost
ISG pumps provide reliable pressure boost for fire hydrant and sprinkler systems in buildings where municipal water pressure is insufficient. The robust construction and straightforward maintenance make them suitable for life-safety applications.
Why Choose Chaodun ISG Series Pumps
Chaodun’s ISG series vertical in-line centrifugal pumps combine proven hydraulic design with practical installation features. The direct inline mounting, top pull-out maintenance access, and broad medium compatibility across six derivative types make this series a practical choice for engineers designing water supply, HVAC, chemical transfer, and fire protection systems. Each pump is manufactured to recognized industry standards and undergoes pressure testing to ensure reliable long-term operation.