Marine Hand Bilge Pump

I. Product Overview

Marine Hand bilge pumps serve as the "manual power core" of ship emergency drainage systems, specifically designed to remove accumulated water from bilge compartments during power outages, mechanical failures, or other emergencies. By manually rotating the crank handle to drive piston or diaphragm structures, they draw bilge water (containing small amounts of sediment and oil) from low-lying compartments and discharge it overboard, preventing the ship from losing stability due to excessive water accumulation. Constructed with cast iron (HT200), wear-resistant cast iron (KmTBCr15Mo), or stainless steel (316L) as the main material, they achieve self-priming and low-pressure drainage through purely mechanical transmission, without requiring electrical or hydraulic assistance. They are compatible with bilge water media containing ≤3% solids. The pump body undergoes anti-corrosion treatment and enhanced sealing, with a service life of ≥10 years in -10℃~60℃ environments. It meets IMO International Convention for the Safety of Life at Sea (SOLAS Chapter II-1) and emergency drainage equipment certification requirements of classification societies such as RS, LR, ABS, and CCS, widely used in emergency bilge drainage systems of cargo ships, fishing vessels, passenger ships, and other vessel types.

II. Core Technologies and Material Characteristics

1.Material Selection and Performance

2.Key Technical Parameters

Flow range: 50-500L/min, with a single continuous operation at 30 rpm discharging 150-300L of water, meeting emergency drainage needs of small and medium-sized compartments

Lift coverage: 5-15m, adapting to drainage heights from the bilge to overboard (including filter and elbow resistance losses) to ensure smooth water discharge

Medium compatibility: Capable of conveying bilge water containing small amounts of sediment (particle size ≤5mm), oil (concentration ≤5%), temperatures from -10℃ to 60℃, and solid content ≤3%

Self-priming performance: Self-priming height ≥2.5m, priming time ≤60 seconds (for clean water), capable of directly drawing water from low-lying bilges without manual priming

Operating force requirement: Crank handle operating force ≤50N (approximately 5kgf), enabling one person to discharge 300-500L of water by continuous cranking for 5 minutes, meeting initial emergency drainage needs

3.Safety and Anti-Clogging Design

Debris-proof structure: Suction inlet equipped with 8mm aperture filter, combined with wide flow channels (diameter ≥50mm), allowing passage of fibrous impurities up to 100mm in length, reducing clogging rate by 90% compared to centrifugal pumps

One-way check device: Built-in check valve at the discharge port prevents seawater backflow into the bilge after shutdown, ensuring drainage results are maintained

Tilt resistance: Elastic fixing between pump body and base allows the pump to withstand ship heel of ±20° and trim of ±10° with flow rate ≤10%

III. Technical Advantages and Innovative Design

1. Emergency Drainage Efficiency

Dual-cylinder reciprocating structure: Adopts main and auxiliary dual-piston alternating design, completing 2 suction-discharge cycles per crank rotation. Drainage flow is 70% higher than single-cylinder pumps with pressure fluctuation ≤±0.05MPa.

Labor-saving transmission system: Uses "gear reduction + crank connecting rod" combined mechanism to amplify crank torque by 4 times, reducing operating force by 40% compared to traditional hand pumps at the same drainage flow, suitable for continuous operation in emergencies.

Foldable crank design: Crank features a foldable structure with an extended length of 800mm (labor-saving lever) and folded length of 400mm, saving storage space and facilitating portability to different compartments.

2. Wear and Corrosion Resistance Enhancement

Piston surface hardening: Stainless steel pistons undergo nitriding treatment (hardness HV600), improving resistance to sediment wear by 50% compared to ordinary stainless steel, extending service life to 10,000 operations.

Cast iron pump inner wall protection: HT200 pump chambers are sprayed with a ceramic coating (0.2mm thickness), resisting sewage erosion and showing no rust after 2,000 hours of immersion in 3% salt spray environment.

3. Ship Emergency Adaptability

Portable design: Single unit weight ≤25kg (300L/min model) with lifting eyes and 10m drainage hose, enabling rapid transfer to flooded compartments to meet multi-point emergency drainage needs.

Low-temperature startup optimization: In -10℃ environments, pump transmission parts are filled with low-temperature grease (dropping point ≥-20℃) to ensure smooth crank rotation without jamming, suitable for use in cold regions.

IV. Typical Application Scenarios

1. Routine Emergency Drainage

Cargo hold water removal: When cargo holds of dry cargo ships accumulate water due to hatch leaks, crew use cast iron Hand bilge pumps (flow 200-300L/min, pressure 0.6MPa) to insert hoses into the flooded area. Continuous cranking for 10 minutes discharges 5m³ of water, preventing cargo from getting wet.

Engine room seepage treatment: When engine rooms of passenger ships seep water due to aging seals, stainless steel hand pumps (flow 100-150L/min, pressure 0.8MPa) suction funnels quickly drain oil-water mixtures, preventing equipment from being submerged.

2. Special Working Condition Drainage

Fishing vessel hold dredging: When fishing holds of trawlers accumulate fish scales and bone fragments, wear-resistant cast iron hand pumps (flow 250-300L/min, pressure 0.7MPa) draw in the mixture through coarse filters and discharge it overboard via drainage hoses, reducing bilge .

Post-collision emergency drainage: When ships collide and water enters through the hull, portable stainless steel hand pumps (flow 150-200L/min) connect to drainage pipelines. Four people taking turns can discharge 20m³ of water in 30 minutes, time for repairs.

3. Extreme Environment Drainage

Polar low-temperature drainage: During navigation in -10℃ ice zones, stainless steel hand pumps with insulation jackets (flow 100-150L/min) discharge bilge water containing trace ice crystals. Crank operating force ≤55N ensures normal operation in low temperatures.

Tropical high-temperature drainage: In 45℃ engine room environments, cast iron hand pumps maintain a surface temperature ≤50℃ after continuous drainage for 1 hour, posing no scalding risk and suitable for long-term operation.

V. Selection and Maintenance Specifications

1. Key Selection Parameters

Bilge water type: Cast iron pumps for clean fresh water; wear-resistant cast iron pumps for sediment and fishing residues; stainless steel pumps for oil-contaminated seawater

Flow calculation: Configure 2 times the maximum water accumulation rate of the compartment (e.g., for a cargo hold accumulating 5m³/h, recommend flow ≥10m³/h)

Pressure requirements: 0.3-0.6MPa for low-level compartment drainage; 0.6-1.0MPa for high-level compartments or long-distance drainage

2. Maintenance Points

Daily inspection: Crank 30 turns weekly to check for pump leaks and suction smoothness, ensuring availability in emergencies

Regular maintenance: Disassemble and clean pistons and valve seats every 6 months, replace aging seals (oil-resistant nitrile rubber), and apply calcium-based grease to transmission parts

Anti-clogging maintenance: Flush pump chambers with clean water after each use to remove residual sediment; inject anti-rust oil (e.g., No.20 machine oil) into the pump before long-term storage

3. Compliance Inspection

Annual classification society inspection focusing on verifying drainage flow stability (fluctuation ≤±15%), self-priming performance, and tilt resistance

Meets SOLAS Convention requirements for ship emergency drainage systems, ensuring emergency drainage can be initiated within 15 minutes after main drainage system failure

VI. Compliance and Certification

International standards: Complies with ISO 8316 Marine Manual Pump Performance Standards and IMO SOLAS Chapter II-1 Emergency Drainage Equipment Specifications

Classification society certifications: Obtained type approval for Hand bilge pumps from RS, LR, ABS, and CCS (including 1,000 reciprocating cycle tests)

Safety requirements: Pump body sealing performance meets no-leakage under 1.5 times rated pressure, complying with ship watertightness specifications