Electric Drive Gland Pump for Barge, Dredger, Tugboat

Product Description

65CWF-4.5 Gland Pump

65CWF-4.5 is gland pump essentially dedicated for dredging pump, which is an independent water cleaning pump with core function of continuously pumping high pressure clean water  into the critical parts of the dredge pump, proventing it from damage by slurry, grave and other heavy load.

This pump is also applied as bilge pump, fire pump, water circulation pump and sewage pump for barge, dredger, tugboat and other engineering ships. 

How It Works:
The gland pump draws water from a seawater tank or fresh water tank and delivers high-pressure clean water to key areas of the dredge pump.
1. Sealing Work for Main Shaft 
Seal water is pumped into the shaft seal chamber to cool and lubricate the packing or mechanical seal. More importantly, it forms a high-pressure water film between the shaft and the seal, acting as a barrier to prevent solid particles from entering and causing severe wear on the shaft.
2. Function onto Suction Side, Clearance between Impeller and Front Liner
Seal water pumped into the suction side and the clearance between the impeller and the front liner, flushes out any sediment that may enter, reducing wear on these components.

3. Works at Casing/Liner Clearance (for Double-Case Pumps)
For pumps with an inner and outer casing, high-pressure water pumped into this annulus creates a "water cushion," balancing pressure and preventing high-pressure slurry from directly impacting the pump housing.

The stable operation of the gland pump is vital. If the sealing water supply is interrupted or pressure drops, concentrated slurry will instantly rush into the clearances. This can lead to rapid sealing failure, shaft scoring, jamming of the impeller and liners, and potentially a catastrophic shutdown.

Attentions in Actual Applications 
In actual application, especially on large cutter suction dredgers, sealing water systems are designed with redundancy and precision:
>Redundant Configuration: Because the pressure requirements for the suction side and the shaft end can differ, large vessels often have dedicated pumps for each duty, plus an additional standby pump for reliability.
>VFD Technology: Dredging conditions can vary significantly, causing the pressure inside the pump casing to change. Modern vessels use VFD-driven seal water pumps that automatically adjust their speed to deliver the precise pressure and flow required, saving energy and ensuring optimal sealing.
>Multi-Stage Pumps: For applications requiring extremely high seal water pressure (e.g., feeding a high-pressure booster pump), multi-stage centrifugal pumps are used to achieve the necessary high head.

Key Parameter
Model No          65CWF-4.5
Flow (m3/h)          40
Head (m)              60
Power (kW)        18.5
Speed (r/min)    2950
Application       pumping sealing water for dredge pump, general marine pumps