GDL Vertical Multistage Centrifugal Pump – Overview
The GDL vertical multistage centrifugal pump is a next-generation water boosting solution designed for high-pressure clean water circulation and pressurization. Building on proven domestic and international pump designs, the GDL series features a vertical sectional structure with an external stainless steel shell, allowing the inlet and outlet to sit on the same horizontal line with identical diameters. This design enables valve-like inline installation directly into piping systems.
By combining the high head capability of multistage pumps, the compact footprint of vertical pumps, and the installation convenience of pipeline pumps, the GDL series delivers efficient energy consumption, smooth operation, and long service life through wear-resistant mechanical seals.
Key Features
- Inline Installation: The inlet and outlet are aligned on the same axis with matching diameters, allowing direct installation into pipelines like a valve — no complex piping modifications needed.
- High Head Performance: Multistage impeller design delivers heads up to 240m, suitable for high-rise building water supply, fire protection, and boiler feed applications.
- Compact Vertical Design: Occupies minimal floor space compared to horizontal multistage pumps, ideal for equipment rooms with limited area.
- Stainless Steel External Shell: Corrosion-resistant exterior casing extends pump lifespan and maintains clean appearance in demanding environments.
- Efficient Hydraulic Model: Optimized impeller and volute geometry reduces energy consumption while maintaining stable pressure output across the operating range.
- Wear-Resistant Mechanical Seal: Premium mechanical sealing minimizes leakage risk and extends maintenance intervals for reliable long-term operation.
Technical Specifications
| Parameter | Specification |
|---|---|
| Flow Rate | 2 – 160 m³/h |
| Head | 10 – 240 m |
| Power | 0.75 – 200 kW |
| Speed | 2900 r/min |
| Inlet/Outlet Diameter | DN25 – DN200 |
| Liquid Temperature | -15°C to +80°C |
| Max Working Pressure | < 2.5 MPa (inlet pressure + closed-valve pressure) |
| Ambient Temperature | Below 40°C |
| Relative Humidity | ≤ 95% |
| Seal Type | Wear-resistant mechanical seal |
Model Designation Example
Example: 50 GDL 12-15 X5
- 50: Nominal inlet and outlet diameter is 50 mm
- GDL: GDL Vertical Multistage In-Line Centrifugal Pump
- 12: Rated flow is 12 m³/h
- 15: Rated single-stage head is 15 m
- X5: Number of stages is 5
Application Scenarios
High-Rise Building Water Supply
In multi-story residential and commercial buildings, municipal water pressure is often insufficient for upper floors. The GDL pump series provides stable, high-pressure water boosting through parallel pump configurations, ensuring consistent water delivery to all levels. Its compact vertical design fits neatly into pump rooms with limited floor space, while the inline installation eliminates the need for complex piping transitions.
Fire Protection Systems
Fire protection networks require reliable high-pressure water sources that can activate on demand. The GDL multistage pump delivers the necessary head to reach upper floors and remote hydrants, meeting fire protection system requirements with dependable performance.
Boiler Feed and Cooling Water Systems
Industrial boiler systems and cooling water circuits demand consistent pressure and flow for safe, efficient operation. The GDL pump handles clean water and liquids with similar physical and chemical properties, supporting temperature ranges from -15°C to +80°C.
Hot and Cold Clean Water Circulation
For closed-loop hot and cold water circulation systems, the GDL pump’s efficient hydraulic design reduces energy consumption during continuous operation. The stainless steel external casing resists corrosion from water treatment chemicals commonly used in circulation systems.
Installation Guidelines
- Piping Support: Pipeline weight must not rest on the pump body to prevent damage. Use independent pipe supports.
- Pre-Assembled Unit: The pump and motor are factory-aligned as a single unit — no field adjustment required.
- Anchor Bolts: Tighten anchor bolts securely and inspect periodically to prevent loosening that could cause vibration during startup.
- Clean Flow Passage: Before installation, check the pump flow passage for hard debris (stones, iron particles) that could damage internal components during operation.
- Valves and Gauges: Install regulating valves on inlet/outlet piping and pressure gauges near the pump. For high-head applications, add a check valve before the outlet gate valve to prevent water hammer during power loss.
- Suction Applications: For suction lift installations, fit a foot valve and minimize bends in the inlet piping to avoid air leaks that reduce suction performance.
- Filters: Install a filter before the pump inlet to prevent debris from entering and blocking the flow passage.
- Pre-Startup Rotation Check: Rotate the rotor by hand before installing piping — there should be no friction or binding.
Startup and Shutdown Procedure
Pre-Startup Preparation
- Turn the coupling by hand — the impeller should rotate freely without binding.
- Open the inlet valve and open the exhaust valve to fill the pump chamber, then close the exhaust.
- For hot liquid service, preheat the pump gradually at 50°C/h using circulating pumped liquid.
- Rotate the pump several times by hand to allow lubricating water into the mechanical seal faces.
- Jog the motor to confirm correct rotation direction.
Startup and Operation
- Fully open the inlet valve, close the discharge valve.
- Power on the motor. When normal speed is reached, gradually open the discharge valve to the desired operating condition.
- Monitor instrument readings — ensure the motor operates within rated current and bearing temperature stays below 75°C.
Shutdown
- Gradually close the discharge valve, then cut power.
- Close the inlet valve.
- If ambient temperature is below 0°C, drain all liquid from the pump to prevent freezing damage.
Maintenance and Care
Operational Maintenance
- Inlet piping must be fully sealed — no water or air leaks permitted.
- Do not operate the pump in cavitation conditions for extended periods.
- Do not run the motor above rated current at high flow conditions for extended periods.
- Monitor motor current regularly — operate within the design range.
- Supervise the pump during operation to prevent accidents.
- Lubricate bearings every 500 operating hours.
- After extended operation, if noise and vibration increase due to mechanical wear, shut down for inspection. Replace worn parts and bearings as needed. Major overhaul interval is typically one year.
Mechanical Seal Maintenance
- Lubricating fluid for mechanical seals must be clean and free of solid particles.
- Never operate the mechanical seal in dry-running conditions.
- Rotate the pump (motor) several times before startup to prevent sudden startup damage to the mechanical seal.
FAQ
What is the maximum working pressure of the GDL pump?
The maximum working pressure is less than 2.5 MPa, calculated as the sum of inlet pressure plus closed-valve operating pressure.
Can the GDL pump handle corrosive liquids?
For corrosive media or hot liquids, specify special materials when ordering. The standard configuration is designed for clean water and liquids with similar physical and chemical properties.
How often should bearings be lubricated?
Bearings should be lubricated every 500 hours of operation. Regular lubrication extends bearing life and reduces vibration.
What temperature range can the GDL pump handle?
The pumped liquid temperature range is -15°C to +80°C. The ambient environment should be below 40°C with relative humidity not exceeding 95%.
Why is a check valve recommended for high-head installations?
A check valve prevents water hammer during sudden power loss, protecting the pump and piping system from pressure surges that could cause damage.
Why Choose Chaodun Pump
Chaodun Pump manufactures the GDL series with rigorous quality control at every production stage. From precision-machined impellers to factory-tested mechanical seals, each pump undergoes performance verification before leaving the facility. Our engineering team provides installation guidance, startup support, and ongoing technical assistance to ensure optimal pump performance throughout its service life.
For technical specifications, pricing, or application consultation, contact our team today.