Marine Cast Iron Cargo Oil Pump

I. Product Overview

Marine cast iron cargo oil pumps are core equipment in ship oil transportation systems, designed specifically for loading, unloading, and inter-tank transfer of crude oil, diesel, fuel oil, and other petroleum products. Constructed with high-strength ductile iron (QT400-18) or gray cast iron (HT250), they achieve efficient transportation of high-viscosity oils through the principles of gear pumps or screw pumps. Their working principle utilizes volume changes from gear meshing or screw rotation to draw oil from cargo tanks into the pump body, pressurize it, and deliver it via pipelines to shore tanks or other compartments, meeting the needs of ship loading/unloading and oil distribution. The pump body undergoes integral casting and oil-resistant anti-corrosion coating treatment, with a corrosion-resistant service life of ≥10 years in oils with temperatures ranging from -20℃ to 120℃ and sulfur content ≤3.5%. It complies with IMO MARPOL Annex I anti-pollution conventions and classification society certifications (LR, ABS, etc.), widely used in oil tankers, chemical tankers, and multi-purpose cargo ships.

II. Core Technologies and Material Characteristics

1.Cast Iron Material Selection and Performance

2.Key Technical Parameters

Flow range: 50-500m³/h, suitable for 5,000-100,000-ton vessels

Head: 30-120m, meeting requirements for long-distance oil transportation and high-level tank filling

Medium adaptability: Capable of transporting oils with viscosity ≤500cSt, stable operation with impurity particles ≤3mm

Corrosion resistance design: Inner wall coated with PTFE (polytetrafluoroethylene), resistant to oil immersion for 10,000 hours without peeling

Temperature adaptability: Stable operation at -20℃~120℃; high-temperature models withstand 150℃ hot oil

3.Safety Performance

Explosion-proof rating: Motors comply with ATEX Zone 1/2 or IECEx explosion-proof standards, adapting to flammable and explosive environments

Leakage control: Mechanical seals adopt metal bellows structure, leakage ≤2mL/h, equipped with leakage alarm devices

III. Technical Advantages and Innovative Design

1. Efficient Oil Transportation

Twin-screw positive displacement design: Symmetric screw rotors achieve volumetric efficiency ≥95%, maintaining stable flow even at 500cSt viscosity with pulsation rate <3%, avoiding pipeline vibration.Temperature-controlled heating system: Integrates steam jackets or electric heating devices to heat low-temperature high-viscosity oils (e.g., fuel oil) to 50-80℃, reducing transportation resistance and cutting energy consumption by 20%.

2. Safety Protection System

Multi-interlock protection: Integrates temperature, pressure, and liquid level sensors, automatically shutting down when oil overheats (≥130℃), overpressurizes (≥1.2x rated pressure), or runs dry, with response time ≤1 second.

Anti-siphon structure: Outlet equipped with check valves and pressure relief valves to prevent oil backflow and cabin contamination, meeting IMO anti-pollution requirements.

3. Long Life and Low Maintenance

Wear-resistant and anti-adhesive coating: Rotor surfaces sprayed with tungsten carbide alloy (200μm thickness) reach HRC60 hardness, 4x higher wear resistance than ordinary cast iron, with service life exceeding 60,000 hours.

Modular quick-release structure: Pump casing and rotor assemblies use flange quick connections, reducing core component replacement time by 50%, with lifecycle maintenance costs 30% lower than stainless steel pumps.

IV. Typical Application Scenarios

1. Oil Tanker Loading/Unloading Operations

Crude oil transportation: 300,000-ton VLCCs (Very Large Crude Carriers) equipped with ductile iron twin-screw pumps, single-pump flow 300-500m³/h, pressure 2.5MPa, enabling efficient loading/unloading of high-viscosity crude oil with heating systems.

Product oil tankers: 100,000-ton product tankers use gear-type cargo oil pumps, flow 150-250m³/h, allowing quick switching between diesel, gasoline, and other products to avoid cross-contamination.

2. Cargo Ship Oil Management

Fuel oil supply: Multi-purpose cargo ships use cargo oil pumps to transfer fuel oil from storage tanks to main engine daily tanks, flow 50-100m³/h, ensuring continuous fuel supply for power systems.

Inter-tank oil distribution: Chemical tankers (compatible with oil transportation) use screw pumps to balance oil between compartments, flow 80-150m³/h, meeting ship stability adjustment needs.

3. Port and Auxiliary Operations

Terminal loading/unloading pump sets: Port oil depots equipped with cast iron cargo oil pumps, flow 200-400m³/h, providing rapid bunkering for berthed ships with -10℃ cold-start capability.

Emergency oil pumping: Oil spill recovery vessels equipped with self-priming cargo oil pumps, self-priming height ≥6m, capable of extracting surface oil slicks and cooperating with booms for pollution control.

V. Selection and Maintenance Specifications

1. Key Selection Parameters

Oil type: Choose ductile iron screw pumps for crude oil/fuel oil (high viscosity); gray cast iron gear pumps for diesel/gasoline (low viscosity)

Ship tonnage: Single-pump systems for <10,000-ton vessels; dual-pump parallel systems (one in use, one standby) for ≥10,000-ton vessels, with total flow configured at 1.2x loading/unloading efficiency

Environmental conditions: Heating-jacketed models for cold seas; sulfur-resistant coated pump bodies for high-sulfur oils

2. Maintenance Key Points

Daily monitoring: Check bearing temperature (≤75℃), mechanical seal leakage (≤5mL/h), and inlet-outlet pressure difference (≤0.2MPa) every 200 hours

Regular maintenance: Clean suction filters (accuracy ≤5mm) monthly; replace gear oil (for gear pumps) quarterly; inspect heating system performance annually

In-depth maintenance: Conduct rotor clearance testing (allowable wear ≤0.1mm) every 3 years; replace aging seals and re-spray wear-resistant coatings

VI. Compliance and Certification

International standards: Complies with IMO MARPOL Annex I Regulations for the Prevention of Pollution by Oil and ISO 13706 petroleum ship pump system specifications

Classification society certifications: Certified for explosion protection (Ex d IIB T4) and pressure equipment (PED 2014/68/EU) by LR, ABS, DNV GL, etc.

Environmental requirements: Meets MEPC.107(49) oil tanker pump system anti-leakage standards, with leakage ≤0.1L/h