Marine Stainless Steel Fuel Pump

I. Product Overview

Marine stainless steel fuel pumps are the "fuel delivery hub" of ship power systems, designed specifically for storing, filtering, and supplying fuel such as diesel, heavy oil, and residual oil to key equipment like main engines and gas turbines. Constructed with 316L ultra-low carbon stainless steel (022Cr17Ni12Mo2) or 304 stainless steel (06Cr19Ni10) as core materials, they achieve precise delivery of high-viscosity, micro-impurity-containing fuel through gear or screw pump principles. Their working principle involves a power source (electric motor or main engine shaft-driven system) driving rotors to mesh and rotate, generating pressure via volume changes in chambers to draw fuel from tanks, which is then preheated, filtered, and delivered to fuel-consuming equipment such as main engines and generators. Pressure closed-loop control ensures stable supply throughout the process. The pump body undergoes solution treatment and oil-resistant passivation, with a corrosion-resistant service life of ≥12 years in sulfur-containing fuel and high-humidity environments. It meets IMO International Convention for the Prevention of Pollution from Ships (MARPOL) Annex I and fuel system certification requirements of classification societies such as LR and ABS, widely used in fuel supply systems of oil tankers, cargo ships, passenger ships, and engineering vessels.

II. Core Technologies and Material Characteristics

1.Stainless Steel Material Selection and Performance

2.Key Technical Parameters

Flow range: 10-300m³/h, suitable for main engine power 1000-50000kW (e.g., 50000kW main engines require flow ≥150m³/h)

Pressure control: Outlet pressure 0.8-4.0MPa, pressure stability ≤±0.03MPa, ensuring consistent atomization at fuel injectors

Medium compatibility: Capable of conveying fuel with viscosity 20-2000cSt (containing micro catalyst particles ≤50μm) and biodiesel (blend ratio ≤30%)

Temperature resistance design: 316L material withstands continuous high temperatures up to 150℃ (post-preheated heavy oil); 304 material suits low-viscosity fuel ≤80℃

Explosion-proof rating: Motor explosion-proof grade Ex d IIB T4, suitable for Zone 1 hazardous areas (near fuel tanks) to prevent fuel vapor ignition

3.Safety and Metering Design

Equipped with fuel leakage detection sensors, automatically alarming and cutting off power when seal leakage ≥1mL/h

Integrated oval gear flowmeter with metering accuracy ≤±0.5%, meeting fuel consumption statistics and pollution discharge declaration requirements

III. Technical Advantages and Innovative Design

1. High-Viscosity Fuel Delivery Capacity

Twin-screw forced delivery: Adopts male-female screw meshing structure with clearance ≤0.03mm, maintaining volumetric efficiency ≥90% at 2000cSt (50℃) — 20% higher than gear pumps — ideal for heavy oil and residual oil.

Staged preheating system: Integrates 3-stage heating jackets (10-30kW) to gradually heat fuel from ambient temperature to 120℃ (viscosity reduced to 180cSt), avoiding thermal cracking from local overheating.

2. Anti-Pollution and Corrosion Resistance

Self-cleaning filter structure: Inlet features scraper-type filter (80μm precision) to automatically remove carbon particles and gums, maintaining filter pressure difference ≤0.1MPa without shutdowns.

Sulfur corrosion resistance enhancement: 316L stainless steel undergoes 1050℃ solution treatment for uniform Cr and Mo distribution, with pitting resistance equivalent (PREN) ≥40, excelling in H₂S-containing fuel environments.

3. Efficiency and Intelligent Control

Variable frequency speed adaptation: Automatically adjusts speed (500-3000r/min) based on main engine load, dynamically matching fuel flow to power demand, reducing energy consumption by 18% and minimizing throttling losses.

Remote monitoring integration: Supports MODBUS protocol for linkage with ship central control systems, real-time transmission of flow, pressure, and temperature data, with automatic switchover to backup pumps during anomalies (switching time ≤3 seconds).

IV. Typical Application Scenarios

1. Main Engine Fuel Supply

Low-speed diesel engine supply: 150,000-ton bulk carriers use 316L stainless steel screw pumps (flow 80-150m³/h, pressure 2.5MPa) to deliver 120℃ heavy oil (180cSt) to injectors post-purifier, with supply pressure fluctuation ≤±0.02MPa.

High-speed gas turbine supply: LNG carrier gas turbines employ 316L stainless steel gear pumps (flow 30-60m³/h, pressure 3.0MPa) to deliver light diesel to combustion chambers, accommodating 50% flow surges during acceleration (within 10 seconds).

2. Auxiliary Engine and Power Generation Systems

Diesel generator supply: 1000kW cruise ship generators use 304 stainless steel fuel pumps (flow 10-20m³/h, pressure 1.0MPa) with pressure regulators stabilizing diesel at 0.8MPa for stable generator output.

Fuel tank transfer: Oil tankers utilize parallel dual-pump systems (single pump flow 100-300m³/h, pressure 1.5MPa) for fast inter-tank transfer (≤10 minutes for 1000m³ capacity) to prevent cross-contamination.

3. Special Vessels and Extreme Environments

Polar ship low-temperature supply: In -30℃ environments, pumps heat low-temperature diesel (800cSt) to 40℃ (50cSt) via insulation and electric heating (flow 10-50m³/h) for icebreaker main engines.

Drilling platform heavy oil delivery: Offshore platform main diesel engines use 316L stainless steel pumps (flow 50-100m³/h) operating stably in high salt spray (35mg/m³) and humidity (95%), withstanding 3% catalyst particle wear in fuel.

V. Selection and Maintenance Specifications

1. Key Selection Parameters

Fuel type: 316L stainless steel for high-sulfur heavy oil (S≥1%); 304 stainless steel for low-sulfur diesel (S≤0.1%)

Flow configuration: 1.2 times the main engine’s maximum fuel consumption (e.g., 100m³/h consumption requires ≥120m³/h pump flow)

Environmental conditions: Forced cooling models for tropical seas (activated at ≥150℃); -30℃ start-up models for polar regions; wear-resistant models for impurity-containing fuel

2. Maintenance Guidelines

Daily monitoring: Check outlet pressure (fluctuation ≤±0.05MPa), pump casing temperature (≤160℃), and vibration (≤3.5mm/s) every 400 hours

Regular maintenance: Clean inlet filters monthly; replace mechanical seals (oil-resistant fluoroelastomer + silicon carbide) every 1500 hours; calibrate flowmeters semi-annually

In-depth maintenance: Disassemble and inspect every 4 years; re-passivate 316L components; replace gears/screws when wear exceeds 0.05mm

VI. Compliance and Certification

International standards: Complies with ISO 8217 fuel standards and IMO MARPOL Annex I fuel system anti-pollution requirements

Classification society certifications: Passed type approval by LR, ABS, CCS (including 1000-hour high-sulfur fuel operation tests)

Environmental requirements: Fuel leakage collection devices meet MEPC.107(49) standards, with discharges directed to slop tanks for treatment