Marine pump
-
Marine Fire Pump
-
Marine Emergency Fire Pump
-
Marine Ballast Water Pump
-
Marine Fuel Pump
-
Marine Lubricating Oil Pump
-
Marine Bilge Pump
-
Marine Sewage Pump
-
Marine Fresh Water Pump
-
Marine General Pump
-
Marine Cargo Oil Pump
-
Marine Cooling Water Pump
-
Marine Centrifugal Pump
-
Marine Screw Pump
-
Marine Gear Pump
-
Marine Vortex Pump
-
Marine Ejector Pump
-
Marine Diaphragm Pump
-
Marine Piston Pump
-
Marine Hand Pump
-
Marine Pump Parts
Chemical pump
Industrial Pumps
Other pump
Civil Pump
Submersible Pump
Contact us
Fushi Pump Chongqing Co., Ltd
Address: No. 11, Tianxing Avenue, ShuangQiao Industrial Park, Chongqing,China
E-mail: Sales1@fspumps.com
Tel: +86-23-67956606
Fax: +86-23-67956622
Mobil: +86-13452620990
WhatsAPP/WeChat :+86-13452620990
Marine Diaphragm Fuel Pump
Date:2025-07-16Views:
Marine Diaphragm Fuel Pump
I. Product Overview
Marine diaphragm fuel pumps are the "flexible conveying hub" of ship fuel supply systems, designed specifically to convey diesel, heavy oil, low-sulfur fuel, and other fuel types. Through the reciprocating deformation of oil-resistant diaphragms to create volume changes, they achieve negative pressure fuel suction and pressurized conveyance, fundamentally solving the problems of fuel contamination from metal wear particles and conveyance in traditional gear pumps when handling high-viscosity heavy oil. Constructed with stainless steel (316L), cast iron (HT250 + anti-corrosion coating), or aluminum alloy (ADC12 + hard anodization) as the main material, and diaphragms made of oil-resistant fluororubber (FKM) or perfluoroelastomer (FFKM), they are compatible with fuels (sulfur content ≤3.5%) with viscosity 20-1000cSt. The pump body undergoes explosion-proof treatment and precision sealing, with a service life of ≥8 years in -20℃~120℃ environments. It meets IMO Ship Fuel System Safety Specifications (MSC.382(94)) and fuel equipment certification requirements of classification societies such as RS, LR, ABS, and CCS, widely used in fuel supply systems of cargo ship main engines, oil tanker generators, fishing boat diesel engines, and other equipment.
II. Core Technologies and Material Characteristic
1.Material Selection and Performance
Material Type | Characteristic Advantages | Typical Application Scenarios |
Stainless Steel (316L) | Contains 17% Cr, 12% Ni, 2.5% Mo; resistant to high-sulfur fuel (sulfur content ≤3.5%) and seawater erosion; suitable for ocean-going oil tankers (working pressure 0.8-2.0MPa). | Main engine fuel supply systems of ocean-going oil tankers |
Cast Iron (HT250 + anti-corrosion coating) | Low cost, high structural strength (tensile strength ≥250MPa); inner wall sprayed with epoxy resin coating (0.2mm thick); suitable for inland cargo ships (pressure 0.6-1.6MPa). | Auxiliary engine fuel conveying systems of inland cargo ships |
Aluminum Alloy (ADC12 + hard anodization) | Lightweight (density 2.7g/cm³) with excellent heat dissipation; suitable for portable emergency fuel supply; ideal for coastal fishing boats (pressure 0.5-1.0MPa). | Emergency fuel systems of coastal fishing boat diesel engines |
2.Key Technical Parameters
Flow range: 2-20L/min, suitable for equipment power 100-5000kW (e.g., 1000kW generators require flow ≥5L/min)
Output pressure: 0.5-2.5MPa, meeting conveying pressure requirements from fuel tanks to injectors (including filter and pipeline resistance losses)
Medium compatibility: Capable of conveying No.0 diesel, heavy fuel oil (HFO), low-sulfur fuel (sulfur content ≤0.5%), with temperatures ranging from -20℃ to 120℃ (heavy oil requires preheating to above 50℃) and viscosity 20-1000cSt
Self-priming performance: Self-priming height ≥3m, priming time ≤50 seconds (for No.0 diesel), capable of directly drawing oil from low-level fuel tanks without manual filling
Conveyance stability: Flow pulsation rate ≤2%, outlet pressure fluctuation ≤±0.05MPa, ensuring uniform injector atomization (atomized particle diameter ≤50μm)
3.Safety and Explosion-Proof Design
Explosion-proof certification: Motors adopt Ex d IIB T3 Gb explosion-proof grade, suitable for Zone 1 hazardous areas near fuel tanks to prevent oil-gas explosions
Leak-proof structure: Diaphragms and pump covers use stepped sealing (compression 0.8mm) with leakage ≤0.01mL/h, meeting ship explosion-proof sealing standards
Overpressure protection: Built-in overflow valve automatically opens (returning oil to the suction end) when outlet pressure exceeds 1.2 times the rated value, avoiding pipeline rupture
III. Technical Advantages and Innovative Design
1. High-Viscosity Fuel Conveyance Capacity
Gradual flow channel design: Suction section flow channel diameter 30mm, pressure section gradually shrinking to 15mm. By increasing flow velocity (up to 3m/s), it reduces flow resistance of high-viscosity fuel, improving conveyance efficiency of 800cSt heavy oil by 35% compared to traditional diaphragm pumps.
Diaphragm reinforcement technology: Fluororubber (FKM) diaphragms embed high-strength aramid fiber nets with tensile strength ≥18MPa. They operate continuously in 120℃ heavy oil for 6000 hours without aging, with a service life 3 times that of ordinary nitrile rubber.
Intelligent preheating system: Integrates temperature sensors and heating jackets (800W power), automatically adjusting heating power (300-800W) according to fuel viscosity to ensure heavy oil viscosity remains below 300cSt during conveyance.
2. Operational Stability Enhancement
Dual-diaphragm balanced drive: Adopts symmetric reciprocating structure of main and auxiliary dual diaphragms, completing 2 suction-discharge cycles per crank rotation. Flow rate is 50% higher than single-diaphragm pumps with pressure pulsation rate ≤1%, avoiding injector carbon deposition from pressure fluctuations.
Low-friction transmission components: Drive shafts use bronze bushings (friction coefficient ≤0.07) with high-temperature grease (dropping point ≥200℃), achieving transmission efficiency ≥92% and reducing energy consumption by 20% compared to steel bushings.
Gas-liquid separation function: Suction ends integrate spiral gas-liquid separators, automatically discharging bubbles in fuel (separation efficiency ≥99%) to avoid fuel supply interruption caused by "vapor lock."
3. Ship Operating Condition Adaptability
Modular easy-maintenance design: Wear parts such as diaphragms and valve plates use quick-release snap connections, reducing replacement time to ≤15 minutes, 70% shorter than traditional pumps.
Impact and vibration resistance: Pump bodies and bases are connected via spring shock absorbers, withstanding ship heel ±25°, trim ±15°, and vibration acceleration 15g with flow attenuation ≤5%.
Compact layout: Single unit weight ≤40kg (10L/min model), 40% smaller in volume than gear pumps of the same flow, suitable for installation in narrow engine room spaces.
IV. Typical Application Scenarios
1. Main Engine and Generator Fuel Supply
Cargo ship main engine fuel supply: 5000kW cargo ship main engines use 316L stainless steel diaphragm fuel pumps (flow 15-20L/min, pressure 2.0MPa) to convey low-sulfur diesel (0.5% sulfur content) to high-pressure fuel pumps. The dual-diaphragm design ensures stable fuel supply pressure at 1.8±0.05MPa, improving main engine combustion efficiency by 3%.
Oil tanker generator fuel supply: 1000kW diesel generators are equipped with cast iron diaphragm pumps (flow 5-8L/min, pressure 1.5MPa) to convey heavy fuel oil (HFO) to generator injectors. The intelligent preheating system stabilizes fuel temperature at 80℃ (250cSt viscosity), reducing generator operating noise by 5dB.
2. Emergency and Auxiliary Fuel Supply
Fishing boat emergency startup: When main fuel pumps of coastal fishing boats fail, portable aluminum alloy diaphragm pumps (flow 2-3L/min, pressure 0.8MPa) connect to backup fuel tanks via quick connectors. Hand cranking for 3 minutes delivers 6-9L of fuel, meeting diesel engine emergency startup needs.
Fuel tank bottom oil conveyance: When fuel tank levels drop below 10%, stainless steel diaphragm pumps (flow 3-5L/min, pressure 1.0MPa) extract residual fuel (containing small amounts of water) from tank bottoms, which is supplied to auxiliary engines after treatment by oil-water separators, improving fuel utilization by 15%.
3. Extreme Environment Adaptation
Polar low-temperature fuel supply: -20℃ ice zone workboats use 316L diaphragm pumps with insulation layers (flow 8-10L/min) to heat -10℃ low-sulfur diesel to 20℃ (viscosity reduced to 50cSt), ensuring smooth diesel engine startup with no pump body ice blockage.
Tropical high-temperature fuel supply: In 50℃ engine room environments, fluororubber diaphragm pumps (flow 10-12L/min) convey 100℃ high-temperature fuel to turbochargers. The diaphragm's temperature resistance ensures leak-free operation for 8 hours continuously.
V. Selection and Maintenance Specifications
1. Key Selection Parameters
Fuel type: Cast iron/aluminum alloy pumps for light diesel; 316L stainless steel pumps for heavy diesel and high-sulfur fuel; insulated models for polar low-temperature fuel
Flow calculation: Configure 1.2 times the maximum fuel consumption of equipment; e.g., a main engine consuming 100L/h requires flow ≥20L/min (based on 5 hours of operation)
Pressure requirements: 0.5-1.0MPa for low-speed diesel engines; 1.5-2.5MPa for high-speed diesel engines and high-pressure common rail systems
2. Maintenance Points
Daily monitoring: Check outlet pressure (fluctuation ≤±0.05MPa) and leaks every 100 hours; drain water from gas-liquid separators weekly
Regular maintenance: Replace diaphragms (FKM service life 8000 hours/FFKM 12000 hours) every 1500 hours; clean valve groups and filters; apply high-temperature grease to transmission parts
Seasonal maintenance: Check heating jacket performance (heating rate ≥8℃/min) before winter; clean pump body heat sinks in summer to ensure motor temperature ≤80℃ in high-temperature environments
3. Compliance Inspection
Annual classification society inspection focusing on verifying high-viscosity fuel conveyance capacity (flow attenuation ≤8% for 1000cSt) and explosion-proof performance
Meets IMO 2020 global sulfur emission limits, with proven compatibility with low-sulfur fuel (sulfur content ≤0.5%)
VI. Compliance and Certification
International standards: Complies with ISO 8661 Marine Diesel Engine Fuel Systems and IMO MSC.382(94) fuel system safety specifications
Classification society certifications: Obtained type approval for diaphragm fuel pumps from RS, LR, ABS, and CCS (including 1000-hour high-viscosity fuel operation tests)
Environmental requirements: When used with marine fuel purification systems, sulfur oxide (SOx) content in exhaust gas ≤0.5%, meeting international maritime environmental standards