1. Project Background
This project is located in a Southeast Asian country and serves as a large-scale water conservancy hub integrating flood control, agricultural irrigation, and municipal water supply. Since the water intake point is located in the deep-water area at the bottom of the reservoir dam, the project faced two major operational challenges:
Deep-Water Cooling Challenge
The water intake point is located in a deep and nearly stagnant section of the reservoir. Conventional submersible motors rely on natural water circulation around the motor for cooling. In such stagnant water conditions, heat accumulation can easily occur, leading to insulation aging, overheating, or even motor failure.
High Head and Large Flow Requirements
Due to significant seasonal water level fluctuations between dry and rainy seasons, the system must overcome an ultra-high head of 310 meters while maintaining a flow rate of 370 m³/h to meet peak irrigation demands.
Limited Installation Space
The intake structure at the bottom of the dam consists of a horizontal gallery, making it impossible to install a traditional vertical long shaft pump. Therefore, a horizontal installation arrangement was required.
2. Technical Solution: Why Choose a Horizontal Submersible Pump with Cooling Sleeve?
To address these challenges, a standard submersible pump was not suitable. A customized 550QJ370-310-560kW Horizontal Submersible Long Shaft Pump with Cooling Sleeve was selected. Its key advantage lies in solving two critical issues: motor cooling in stagnant water and reliable high-head water transportation.
Forced Circulation Cooling System
This is the most important feature of the project.
Since the motor is installed horizontally in stagnant water, a specially designed stainless steel cooling sleeve is mounted around the motor.
Working Principle:
High-pressure discharge water from the pump outlet is directed through the cooling sleeve, creating a high-velocity cooling water layer that continuously flows around the motor housing.
Performance Benefits:
The cooling system efficiently removes the heat generated by the 560kW high-power motor, ensuring that motor temperature rise remains within the limits of Class F insulation even when water velocity at the reservoir bottom is virtually zero. This effectively eliminates the risk of overheating and unexpected shutdowns.
Mechanical Stability of the Horizontal Structure
Compared with vertical pumps, the horizontal configuration provides a lower center of gravity and is better suited for installation within narrow horizontal intake tunnels.
To withstand the substantial axial thrust generated by the 310-meter head, the pump is equipped with heavy-duty thrust bearings. Combined with the load characteristics of horizontal installation, this design significantly reduces bearing wear and extends service life under high-flow operating conditions.
Precisely Matched Hydraulic Performance
550 mm Well Diameter Compatibility
The compact pump structure perfectly fits the reserved intake pipeline interface.
370 m³/h Large Flow Capacity
A single unit can satisfy peak irrigation demand, reducing the number of pump units required and simplifying maintenance.
310 m Ultra-High Head
The multi-stage impeller design provides sufficient pressure to lift water from the reservoir bottom to the dam crest and deliver it directly to remote booster pumping stations.
3. Equipment Delivery Status
As shown in the project photos, the equipment has completed factory assembly and performance testing prior to shipment.
The entire pump unit is mounted on a heavy-duty steel base and wrapped with multiple protective layers to withstand the high-salinity marine environment and transportation vibrations associated with long-distance shipping to Southeast Asia.
This fully assembled delivery configuration enables rapid installation and commissioning upon arrival at the project site, significantly reducing construction time and ensuring a smooth project schedule.
