Copper Ejector Freshwater Pump

I. Product Overview

Marine copper ejector freshwater pumps are high-efficiency water delivery equipment designed for ship freshwater systems, using tin bronze (CuSn10), aluminum bronze (CuAl9Fe4), or brass (CuZn20) as the main materials. Based on the ejector pump principle (Venturi effect), they enable forced circulation and long-distance transportation of freshwater. The working principle is that high-pressure water forms a high-speed jet through a copper nozzle, creating vacuum negative pressure in the suction chamber to draw in freshwater, which is then pressurized by a diffuser and delivered to the ship's domestic water, main engine cooling, and boiler feed water systems. After solution treatment and passivation coating reinforcement, copper alloys exhibit a corrosion rate <0.01mm/year in fresh water with pH 6-8, suitable for freshwater supply in merchant ships, passenger ships, and special vessels, meeting IMO Guidelines for Safe Ship Drinking Water Operations and classification society certifications (LR, ABS, etc.).

II. Core Technologies and Material Characteristics

1.Copper Alloy Material Selection and Performance

2.Key Technical Parameters

Flow range: 20-300m³/h, suitable for 500-20,000-ton vessels

Head: 15-50m, self-priming height ≥10m, start-up response time ≤15s

Efficiency index: Ejector efficiency ≥70%, 15% more energy-efficient than traditional centrifugal pumps

Corrosion resistance design: Chromate passivation treatment, 3,000-hour salt spray test passed without rust, 3x improved fresh water erosion resistance than cast iron

Temperature adaptability: Stable operation at -10℃~80℃

III. Technical Advantages and Innovative Design

1. Efficient Water Transportation and Anti-Scaling Capability

No electrochemical corrosion: Copper alloys form a cuprous oxide protective film when in contact with fresh water, with corrosion resistance 2x higher than stainless steel in carbonate-containing fresh water, reducing pipeline scaling risks.

Self-cleaning flow channel: Nozzles and diffusers adopt large-curvature streamlined design, combined with the antibacterial effect of copper ions, reducing biofilm attachment probability and extending the maintenance cycle to 24 months.

2. Extreme Condition Adaptability

Vibration-resistant structure: Integrated copper alloy casing dynamically balanced, vibration value ≤2.0mm/s, adapted to high-frequency vibration environments of ship main engines, reducing pipeline fatigue fracture risks.

Low-temperature protection design: Tin bronze with electric tracing system can transport fresh water at -10℃, preventing pipeline freezing, suitable for cold-zone vessels.

3. Low Maintenance and Cost Advantages

Modular quick-release: Pump body and pipelines use flange quick-connect design, reducing single-component replacement time by 60%, with maintenance costs 35% lower than stainless steel pumps.

Self-lubricating properties: Tin bronze impellers in fresh water with sediment content ≤100ppm have a wear rate only 1/4 of cast iron, reducing bearing replacement frequency.

IV. Typical Application Scenarios

1. Ship Domestic Water Systems

Passenger ship daily water supply: Brass ejector pumps provide domestic fresh water for cruise ships, flow 60-120m³/h, meeting drinking water standards with reverse osmosis devices to ensure passenger water demand.

Crew drinking water purification: Tin bronze ejector pumps linked with UV disinfection equipment deliver WHO-standard drinking water, flow 30-80m³/h, adapted to multi-deck cabin negative pressure drainage.

2. Power System Cooling

Main engine freshwater cooling: Aluminum bronze ejector pumps provide high-pressure freshwater circulation for ocean-going cargo ship main engines, flow 150-250m³/h, controlling cylinder liner temperature at 85-95℃ with plate heat exchangers.

Generator heat dissipation: Brass ejector pumps provide forced cooling for ship auxiliary generators, flow 80-150m³/h, controlling winding temperature ≤110℃ to avoid overheating failures.

3. Special-purpose Water Supply

Boiler feed water: Aluminum bronze ejector pumps (head ≥40m) stably supply water for ship boilers, avoiding dry burning risks, flow 20-60m³/h, adapted to steam-powered ships.

LNG ship low-temperature systems: Tin bronze pumps transport -20℃ ethylene glycol solution, combined with insulated pipelines to cool LNG pump cabin equipment, flow 50-100m³/h, ensuring safe operation of low-temperature equipment.

V. Selection and Maintenance Specifications

1. Key Selection Parameters

Water quality conditions: Choose brass for conventional fresh water, tin bronze for fresh water with trace corrosive ions, aluminum bronze for high-temperature fresh water

Temperature requirements: Select aluminum bronze for >80℃, tin bronze or brass for ≤80℃

Flow matching: Configure at 1.5x actual water consumption, e.g., 1,000-passenger ships recommend flow 70-100m³/h

2. Maintenance Key Points

Daily monitoring: Inspect nozzle wear (allowable loss ≤0.5mm) and bearing temperature (≤65℃) every 500 hours

Regular maintenance: Clean suction strainers (accuracy ≤5mm) quarterly, remove pump cavity scale with 2% citric acid solution annually

In-depth maintenance: Ultrasonic testing every 3 years, reapplying passivation coating and replacing seals with wear exceeding 30%

VI. Compliance and Certification

International standards: Complies with IMO Guidelines for Safe Ship Drinking Water Operations and ISO 8680 ship water supply system specifications

Classification society certifications: Passed LR Rules for the Classification of Ships and ABS Rules for Building and Classing Ships

Hygiene standards: Components in contact with fresh water comply with NSF 61 certification; copper ion emissions ≤0.1ppm, 100% recyclable material