In-Line Centrifugal Pump

In-Line Centrifugal Pumps are a type of rotodynamic pump featuring suction and discharge ports aligned along a common axis, allowing for direct in-line installation within piping systems. This configuration provides a compact, straight-through flow path that minimizes installation footprint and is well suited for continuous-duty water and liquid transfer applications in water and wastewater treatment facilities.

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The in-line design simplifies both installation and ongoing maintenance, as the pump can be supported directly by the pipeline or with optional baseplates. These pumps are commonly employed for process water transfer, recirculation in filtration systems, and chemical dosing loops, ensuring reliable operation in facilities where space, accessibility, and operational continuity are critical considerations.

• Water Treatment Plants:  

  • Process water transfer between treatment stages  

  • Recirculation in filtration systems (media or membrane)  

  • Chemical dosing loop circulation (side-stream)

• Wastewater Treatment Plants:  

  • Sludge return and recirculation  

  • Effluent transfer between basins/tanks  

  • Filter backwash water recirculation

• Routine Operator Tasks:  

  • Daily: Observe for unusual pump/motor noise, leaks, or vibration  

  • Daily: Check and record discharge pressure and flow rate  

  • Monthly: Inspect mechanical seal/gland for leakage  

  • Annual: Verify motor alignment and coupling condition

• Maintenance:  

  • Lubricate motor bearings as per manufacturer  

  • Inspect and replace wear components (e.g., seals, impeller) as needed  

  • Clean pump/motor exterior to aid cooling

• Safety/Inspection/Troubleshooting:  

  • Lock out/tag out (LOTO) before maintenance  

  • Monitor bearing temperatures/vibration for misalignment/wear  

  • Check pressure relief and isolation valves for correct function

• Pump Casing (Body): Houses internal components and directs fluid flow; material selection based on process liquid and pressure rating.
• Impeller: Rotating part imparts velocity and pressure; select for type, diameter, and corrosion/abrasion resistance.
• Motor: Powers the impeller; select for voltage, horsepower/kilowatts, and efficiency.
• Shaft and Coupling: Transmits torque; selection of shaft material and sealing (mechanical seal or packing gland).
• In-Line Suction and Discharge Nozzles: Axial fluid entry/exit ports; select for size, connection type (flange/threaded).
• Support Foot/Baseplate (Optional): For stability and alignment in larger/heavier pumps; sometimes omitted for pipe-supported installations.

• Flow Rate (Q): 10–2000 US GPM (gallons per minute) typical range
• Total Dynamic Head (TDH): 10–250 feet (3–75 meters) typical
• Liquid Type/Temperature: Clear or filtered water, < 120°F (50°C); check limits for wastewater/chemically aggressive media
• Solids Size: Typically < 3 mm; larger solids may clog the impeller
• Motor Power: 1–100+ HP (0.75–75 kW) depending on duty
• Pipe Connection Size: 1"–12" nominal diameter

• 22 11 23: Domestic Water Pumps
• 22 14 29: Sump Pumps
• 43 21 39: Process Pumps (Water and Wastewater)
• 43 25 13: In-Line Centrifugal Pumps

• Bell & Gossett (Xylem): e-80 Series Vertical In-Line Centrifugal Pump
• Grundfos: TPE Series In-Line Pump
• Armstrong Fluid Technology: 4300 Series Vertical In-Line Pumps

• End-Suction Centrifugal Pump  

  • Advantages: Generally better suited for higher capacity; easier maintenance access.  

  • Disadvantages: Larger footprint, may require more floor space and complex foundation.

• Split-Case Centrifugal Pump  

  • Advantages: High flow rates and high efficiency for large-volume applications; easy impeller access for service.  

  • Disadvantages: Larger, more expensive; less suitable for compact installations.

• Submersible Pump  

  • Advantages: Can be installed directly in sump or tank; eliminates need for some piping and pump room.  

  • Disadvantages: Service and inspection are more difficult; not as suitable for inline pipe applications.