Product Overview
The ISW series horizontal single-stage centrifugal pump represents a modern generation of efficient, compact, and reliable pumping equipment. Developed based on the performance parameters of IS and IR type centrifugal pumps and referencing ISO 2858 standards, the ISW series incorporates optimized hydraulic models for superior energy efficiency. The entire range is designed as a horizontal, end-suction centrifugal pump with a direct-coupled motor — delivering high performance in a minimal footprint.
Available in multiple material and configuration variants, the ISW series covers applications ranging from clean water circulation and hot water heating to chemical processing and explosive liquid transfer. Each variant shares the same robust platform: a compact horizontal layout, precision-balanced impeller, premium mechanical seal, and a directly coupled motor for smooth, vibration-free operation.
Model Variants and Applications
| ISW | Standard horizontal centrifugal pump for clean water and liquids with similar properties. Medium temperature ≤ 85°C. Suitable for industrial and municipal water supply, high-rise building pressurization, marine applications, garden irrigation, fire protection boost, HVAC circulation, and bathroom water circulation. |
| ISWR | Hot water circulation pump for energy, metallurgy, wood processing, chemical, textile, paper, hotel, and central heating applications. Medium temperature ≤ 120°C. |
| ISWH | Chemical centrifugal pump for petroleum, chemical, metallurgy, power, paper, food, pharmaceutical, and synthetic fiber industries. Handles corrosive liquids at -20°C to +105°C. |
| ISWY | Explosion-proof oil pump for petroleum, light textile, chemical, and machinery industries. Handles flammable and explosive liquids at temperatures ≤ 120°C. |
| ISWHY | Stainless steel explosion-proof chemical centrifugal pump for flammable and explosive chemical liquids. |
| ISWD / ISWRD / ISWHD / ISWYD / ISWHYD | Low-speed variants designed for environments requiring ultra-low noise — particularly HVAC chilled water and cooling water circulation and end-point pressurization. |
Key Features
Compact Structure — 30% Less Floor Space
The horizontal, integrated pump-motor design reduces footprint by 30% compared to conventional horizontal pumps. With an IP54 outdoor-rated motor option, no pump room is required — the unit can be installed outdoors directly.
Smooth Operation — Low Noise and High Concentricity
The pump and motor are directly coupled, eliminating intermediate coupling components and improving operational stability. The impeller undergoes precise dynamic and static balancing, ensuring vibration-free, quiet operation. Bearing life is extended, and the working environment is significantly improved.
Premium Mechanical Seals
The shaft seal uses high-quality mechanical seals with hard alloy (tungsten carbide) faces — wear-resistant, leak-free, and long-lasting.
Optimized Hydraulic Model
Advanced hydraulic design delivers high efficiency and excellent overall performance across the operating range.
Drainage and Pressure-Tap Ports
A drain port on the lower side of the pump body and pressure-tap ports on the inlet and outlet flanges ensure proper pump operation and maintenance accessibility.
Standardized Piping Layout
Horizontal inlet and vertical upward outlet configuration facilitates straightforward piping arrangement and system integration.
Technical Parameters
| Maximum System Working Pressure | 1.6 MPa (inlet pressure + pump head ≤ 1.6 MPa). For higher pressures, cast steel wetted and connecting components are available on request. |
| Medium | Clean water or liquids with similar physical-chemical properties. For media containing fine particulates, wear-resistant mechanical seals are available on request. |
| Ambient Temperature | ≤ 40°C |
| Altitude | ≤ 1,000 m |
| Relative Humidity | ≤ 95% |
| Medium Temperature (ISW) | ≤ 85°C |
| Medium Temperature (ISWR) | ≤ 120°C |
| Medium Temperature (ISWH) | -20°C to +105°C |
| Medium Temperature (ISWY) | ≤ 120°C |
| Motor Enclosure | IP54 (standard) / IP55 (option) |
Model Designation System
| ISW | Horizontal Centrifugal Pump |
| ISWR | Horizontal Hot Water Centrifugal Pump |
| ISWH | Horizontal Chemical Centrifugal Pump |
| ISWY | Horizontal Explosion-Proof Oil Pump |
| ISWHY | Horizontal Explosion-Proof Chemical Centrifugal Pump |
| Suffix D | Low-Speed Type |
| 100 | Nominal Inlet/Outlet Diameter (mm) |
| 160 | Nominal Impeller Diameter (mm) |
| I | Extended Flow Rate Type |
| A | Impeller First Trim |
| B | Impeller Second Trim |
Installation Guidelines
- Piping weight must not rest on the pump body — provide independent supports to prevent pump deformation and protect operational life.
- The pump and motor are an integrated assembly, requiring no alignment during installation — greatly simplifying setup.
- Anchor bolts must be tightened firmly to prevent vibration impact on pump performance during startup.
- Before installation, inspect the pump flow passage for any hard objects (stones, iron pieces, etc.) that could damage the impeller or pump body.
- Install regulating valves on both inlet and outlet piping, and a pressure gauge near the outlet, to ensure operation within rated head and flow range.
- For suction-lift applications, install a foot valve and ensure the inlet piping has no excessive bends and is free of air or water leaks.
- If a check valve is installed on the discharge line, place it outside the gate valve.
- After installation, manually rotate the pump shaft — there should be no grinding noise or binding.
- Installation methods: rigid connection or flexible connection.
Start-Up and Shutdown Procedures
Pre-Start Preparation
- Manually turn the motor fan — the impeller should rotate freely without binding.
- Open the inlet valve and the air vent valve until the pump chamber is fully flooded, then close the vent.
- Hand-turn the pump to allow lubricant to reach the mechanical seal faces.
- Jog the motor to confirm correct rotation direction.
Start-Up and Running
- Fully open the inlet valve; close the discharge valve.
- Energize the motor. When the pump reaches normal speed, gradually open the discharge valve and adjust to the desired operating point.
- Monitor instrument readings, check seal leakage (normal: ≤ 3 drops/min), and verify motor/bearing temperature rise ≤ 70°C. Address any abnormalities immediately.
Shutdown
- Gradually close the discharge valve, then cut power.
- Close the inlet valve.
- If ambient temperature drops below 0°C, drain all liquid from the pump to prevent freeze damage.
- For extended shutdowns, disassemble, clean, and properly store the pump.
Maintenance Schedule
During Operation
- Inlet piping must be completely sealed — no air ingress.
- Never operate the pump under cavitation conditions for extended periods.
- Never run the motor above rated current at high flow conditions for extended periods.
- Regularly check motor current — it must not exceed the rated value.
- Assign dedicated personnel for monitoring during operation.
- Grease bearings every 500 operating hours. Motors above 11 kW have a grease fitting for direct high-pressure gun injection.
- After extended operation, if noise and vibration increase due to mechanical wear, stop for inspection and replace worn parts or bearings as needed. Major overhaul interval: approximately 1 year.
Mechanical Seal Maintenance
- Seal lubrication must be clean and free of solid particles.
- Never operate the mechanical seal in dry-running conditions.
- Before startup, manually rotate the pump (motor) several turns to prevent sudden start-up from damaging the seal faces.
Why Choose Chaodun Pump?
As a professional pump manufacturer, Chaodun Pump designs and produces the ISW series with rigorous quality control — from hydraulic model optimization to precision impeller balancing and mechanical seal selection. Every unit undergoes factory performance testing before shipment. Our engineering team provides application consulting,选型 guidance, installation support, and after-sales service worldwide.
Contact us today for detailed performance curves, dimension drawings, and technical documentation for your specific ISW application.