The CDLF Light Vertical Multistage Stainless Steel Centrifugal Pump is a non-self-priming vertical multistage centrifugal pump designed for reliable high-pressure water delivery in demanding applications. Coupled directly to a standard fully enclosed fan-cooled motor through a shaft-linked coupling system, this pump integrates a pull-rod bolt assembly that secures the pressure cylinder, flow-pass components, and inlet/outlet sections into a compact inline configuration — with both suction and discharge ports aligned on the same base line for simplified piping layouts.
Why Multistage Design Matters for High-Pressure Applications
Unlike single-stage pumps that struggle to generate sustained pressure above 50m head, the CDLF’s multistage impeller arrangement stages pressure incrementally across multiple impeller-diffuser pairs. This enables the pump to achieve heads up to 280 meters while maintaining stable operation — a critical requirement for high-rise building water supply, boiler feed systems, and industrial process lines where downstream pressure must be maintained consistently.
With a flow range spanning 2 to 200 m³/h and motor power options from 0.75 kW to 110 kW, the CDLF series covers a broad operating envelope. Port sizes from DN25 to DN150 accommodate connections from small instrument lines to main distribution headers, all running at a nominal speed of 2900 RPM on a standard 50Hz / 380V three-phase supply.
Intelligent Dry-Run & Overload Protection
One of the most common causes of premature pump failure is dry running — operating without sufficient liquid to lubricate mechanical seals and dissipate heat. The CDLF series can be equipped with an optional intelligent protection controller that monitors for dry running, phase loss, and motor overload conditions, automatically shutting down the pump before damage occurs. This built-in safeguard extends equipment life and reduces unplanned downtime in critical service applications.
The motor carries an IP54 / IP55 protection rating and Class F insulation, suitable for operation in ambient temperatures up to 40°C and altitudes up to 1000m. For installations in hotter or higher-altitude environments, the reduced air density impairs motor cooling — in these cases, the manufacturer recommends uprating the motor power to compensate.
Wide Temperature Range & Media Compatibility
The CDLF handles two distinct liquid categories:
- CDL models: for non-corrosive liquids such as potable water, cooling water, and HVAC circulation fluid.
- CDLF models: for mildly corrosive liquids including treated wastewater, light chemical solutions, and desalination feed streams.
Liquid temperature ranges from -15°C to +70°C in the standard configuration, and up to +105°C in the hot-water variant — making the CDLF suitable for boiler condensate return, hot water circulation, and thermal oil transfer applications.
Key Application Scenarios
| Sector | Typical Use |
|---|---|
| Building Services | Water plant filtration & distribution, high-rise booster, main-line pressure maintenance |
| Industrial | Process water systems, high-pressure washing, fire protection, machine tool coolant supply |
| Water Treatment | Ultrafiltration feed, reverse osmosis pressurization, distillation systems, swimming pool circulation |
| HVAC | Cooling and air conditioning circulation, boiler feedwater and condensate return |
| Agriculture | Farm irrigation, sprinkler systems, drip irrigation pressurization |
Installation Best Practices
Proper installation is essential for long service life. Key guidelines include:
- Ventilation clearance: Maintain at least 150mm between the pump/motor and surrounding walls or obstacles to ensure adequate airflow for the motor cooling fan.
- Minimize suction losses: Keep the inlet piping as short and direct as possible to reduce friction losses and NPSH requirements.
- Check valve protection: Install a check valve in the discharge line to prevent backflow when the pump stops. For boiler feed applications, a check valve is mandatory between the pump and the boiler.
- Solid foundation: Mount the pump on a concrete base or rigid bracket rated for the combined weight of the pump, piping, and fluid — never allow pipe weight to load the pump casing directly.
- Inlet filtration: For flows below 8 m³/h, install a strainer mesh 0.5–1m upstream of the suction port to prevent particulate ingress, especially when incoming water quality cannot be guaranteed.
- Air pocket prevention: Route suction piping to avoid high points where air can accumulate, which would cause cavitation and loss of prime.
Technical Specifications at a Glance
| Parameter | Value |
|---|---|
| Flow Rate | 2 – 200 m³/h |
| Head | 5 – 280 m |
| Motor Power | 0.75 – 110 kW |
| Speed | 2900 r/min |
| Port Size | DN25 – DN150 |
| Motor Protection | IP54 / IP55 |
| Insulation Class | F |
| Standard Voltage | 50Hz / 380V (other voltages available) |
| Liquid Temperature | -15°C to +70°C (standard); up to +105°C (hot-water variant) |
| Max Ambient Temperature | 40°C |
| Max Altitude | 1000m |
Whether you need reliable pressure boosting for a 30-story residential tower, a clean water circulation pump for a food processing line, or a corrosion-resistant transfer pump for a water treatment plant, the CDLF series delivers multistage performance with the durability of stainless steel construction and the peace of mind of integrated smart protection.