Copper Ejector Bilge Pump

I. Product Overview

Marine copper ejector bilge pumps are high-efficiency drainage equipment designed for ship bilge water discharge, using tin bronze (CuSn10), aluminum bronze (CuAl9Fe4), or brass (CuZn20) as the main materials. Based on the ejector pump principle (Venturi effect), they enable rapid pumping of bilge water (containing oil, sediment, fibrous impurities, etc.). 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 bilge water, which is then pressurized by a diffuser and discharged. After solution treatment and passivation coating reinforcement, copper alloys exhibit a corrosion rate <0.03mm/year in seawater with Cl⁻≤20,000ppm, suitable for bilge drainage in merchant ships, engineering vessels, and special ships, meeting IMO MARPOL Annex I anti-pollution conventions 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: 50-300m³/h, suitable for 500-15,000-ton vessels

Head: 15-40m, self-priming height ≥8m, start-up response time ≤20s

Impurity passing capacity: Passes ≤8mm solid particles and ≤15mm fibrous impurities, clogging risk reduced by 95%

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

Temperature adaptability: Stable operation at -10℃~70℃

III. Technical Advantages and Innovative Design

1. Corrosion Resistance and Anti-Clogging Capability

No electrochemical corrosion: Copper alloys form a cuprous oxide protective film when in contact with seawater, with corrosion resistance 1.5x higher than stainless steel in sulfide-containing bilge water, suitable for harsh drainage environments.

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

2. Extreme Condition Adaptability

All-attitude drainage: Stable drainage under ship trim 25° and list 12°, automatically adjusting flow with tilt sensors to ensure emergency drainage efficiency.

Anti-sediment wear: Aluminum bronze impeller surface with tungsten carbide spraying (thickness 150μm), wear rate only 1/4 of cast iron in bilge water with sediment content ≤300ppm.

3. Low Maintenance and Cost Advantages

Modular quick-release: Pump body and pipelines use flange quick-connect design, reducing single-component replacement time by 70%, with maintenance costs 40% lower than stainless steel pumps.

Oil-free lubrication: Self-lubricating properties of copper alloys reduce bearing wear, eliminating the need for frequent lubrication, compliant with MEPC.279(70) environmental requirements.

IV. Typical Application Scenarios

1. Merchant Ship Bilge Drainage

Cargo ship engine room bilge: Tin bronze ejector pumps drain engine room water with lubricating oil, flow 100-200m³/h, combined with oil-water separators for compliant discharge (oil content ≤15ppm).

Passenger ship sanitary bilge: Brass ejector pumps provide negative pressure drainage for multi-deck cabins, self-priming height 9m, avoiding odor accumulation, adapted to inland passenger ships.

2. Engineering and Special Vessels

Dredger bilge: Aluminum bronze ejector pumps pass ≤8mm sediment particles, flow 150-300m³/h, outstanding wear resistance in dredging operations.

LNG ship bilge: Tin bronze resists low temperature (-10℃), combined with insulated pipelines to drain low-temperature bilge water after LNG leakage, ensuring system safety.

3. Port and Fishing Vessels

Port tugs: Brass ejector pumps with vector jet technology enable 360° steering drainage, quickly discharging bilge water during towing operations to improve efficiency.

Fishing vessels: Tin bronze pumps resist seawater corrosion, with service life 1.8x longer than cast iron pumps in high-salinity (>3.5%) fishing grounds.

V. Selection and Maintenance Specifications

1. Key Selection Parameters

Water quality conditions: Choose brass for fresh water, tin bronze for seawater, aluminum bronze for sediment-laden seawater

Ship conditions: Select aluminum bronze for ocean-going/engineering ships, brass or tin bronze for inland vessels

Flow matching: Configure at 1.5x maximum bilge water generation, e.g., 5,000-ton cargo ships recommend flow 120-180m³/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 grilles (accuracy ≤10mm) quarterly, remove pump cavity scale with 3% 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 MARPOL Annex I Regulation 15 for bilge water discharge and ISO 15085 ship drainage system specifications

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

Environmental requirements: Copper ion emissions ≤0.1ppm, 100% recyclable material, compliant with MEPC.279(70) anti-pollution standards