Marine Cast Steel Fresh Water Pump

I. Product Overview

Marine cast steel fresh water pumps are core equipment in ship fresh water supply systems, designed specifically for scenarios such as domestic water supply, equipment cooling, and boiler feed water. Constructed with high-strength alloy cast steel (WC6) or carbon cast steel (WCB), they achieve efficient transportation of clean or low-impurity fresh water through centrifugal pump principles. Their working principle involves a power source (electric motor or diesel engine) driving an impeller to rotate, generating centrifugal force to draw fresh water from storage tanks, pressurize it, and deliver it via pipelines to water-consuming points such as living quarters, engine rooms, or boilers, ensuring stable fresh water supply on board. The pump body undergoes integral forging and rust-proof treatment, with a corrosion-resistant service life of ≥15 years in fresh water media. It meets the IMO International Convention for the Safety of Life at Sea (SOLAS) and certification requirements of classification societies such as LR and ABS, widely used in passenger ships, cargo ships, oil tankers, and offshore platforms.

II. Core Technologies and Material Characteristics

1.Cast Steel Material Selection and Performance

2.Key Technical Parameters

Flow range: 10-300m³/h, suitable for ships with 50-5000 passengers and equipment water consumption

Head: 15-80m, meeting transportation requirements from fresh water tanks to high-rise living quarters, boilers, and other elevated water points

Medium compatibility: Capable of transporting fresh water with hardness ≤500mg/L, distilled water, and softened water with small amounts of additives (pH 6-8)

Corrosion resistance design: Inner walls adopt epoxy phenolic resin coating (thickness ≥200μm), passing 3000-hour salt spray test without rust

Temperature adaptability: Stable operation at -10℃~120℃; high-temperature models can withstand 150℃ boiler feed water

3.Safety and Sanitary Design

Surface roughness of flow-through components ≤Ra1.6μm, meeting food-grade hygiene standards (FDA 21 CFR 175.300)

Equipped with pressure protection devices, automatically relieving pressure when outlet pressure exceeds 1.1 times the rated value to avoid pipeline bursting

III. Technical Advantages and Innovative Design

1. Efficient and Stable Transportation Capacity

Low cavitation impeller design: Adopts double-suction impeller and streamlined inlet section, reducing required net positive suction head (NPSH) by 30%, ensuring stable water absorption in low-level fresh water tanks with operating efficiency ≥85%.

Wide flow adjustment range: Supports frequency conversion speed regulation (30%-100% of rated flow), automatically adjusting according to water consumption, achieving 25% energy savings and adapting to fluctuations between peak and off-peak domestic water usage.

2. Adaptability to Extreme Environments

Low-temperature anti-freeze design: Pump body integrates electric heating jacket, capable of heating accumulated water in the pump to above 5℃ in -20℃ environment, avoiding impeller damage from freezing with start-up time ≤30 seconds.

Anti-vibration and inclination resistance: Pump body and base adopt spring shock absorption devices with vibration value ≤2.8mm/s, ensuring normal operation when the ship heels 25° or trims 15°, meeting harsh sea condition requirements.

3. Long Life and Low Maintenance

Wear-resistant mechanical seal: Uses silicon carbide-graphite single-end face seal with leakage ≤1mL/h, trouble-free operation cycle exceeding 10,000 hours, twice the service life of traditional seals.

Quick-release structure: Pump cover and body adopt flange quick-connection design, allowing replacement of seals or impellers without disassembling pipelines, with single maintenance time ≤1 hour, 60% shorter than traditional strucures.

IV. Typical Application Scenarios

1. Domestic Water Supply

Domestic water supply for large cruise ships: 3000-passenger cruise ships are equipped with two alloy cast steel fresh water pumps (single pump flow 150-300m³/h) with head 50m, providing domestic water to 15 deck levels through zoned pipelines with pressure stable at 1.5±0.1MPa.

Crew water supply for cargo ships: 500-crew cargo ships use carbon cast steel fresh water pumps with flow 30-50m³/h, providing drinking water and washing water to living quarters, with water quality meeting WHO drinking water standards.

2. Equipment Cooling and Boiler Feed Water

High-pressure boiler feed water: Oil tanker steam boilers are matched with WC6 alloy cast steel fresh water pumps with flow 50-100m³/h and pressure 4.0MPa, heating softened water to 100℃ before injecting into boilers to meet steam generation needs.

Generator cooling: Ocean-going cargo ship generator cooling systems adopt dual-pump parallel configuration, with single pump flow 80-150m³/h and head 30m, controlling cooling water temperature at 40±2℃ to ensure stable generator operation.

3. Special Vessels and Platforms

Fresh water transportation for polar ships: In -30℃ environment, through pump body insulation and heating design, fresh water is prevented from freezing during transportation, providing domestic water to researchers with flow 20-50m³/h.

Fresh water systems for drilling platforms: Offshore platforms use high-temperature fresh water pumps to supply water to steam generators under 120℃ working conditions, with flow 10-80m³/h and pressure 5.0MPa, adapting to high-temperature operating environments on platforms.

V. Selection and Maintenance Specifications

1. Key Selection Parameters

Water usage type: Alloy cast steel (WC6) high-temperature type for boiler feed water and high-temperature equipment; carbon cast steel (WCB) economical type for domestic water and general cooling

Flow configuration: Calculated as 1.2 times the sum of 200L/person/day domestic water consumption and equipment water consumption; for example, 1000-passenger ships recommend total flow ≥240m³/d (i.e., 10m³/h)

Environmental conditions: -30℃ start-up type for polar ships; high-temperature adaptive type with heat sinks for tropical sea areas

2. Maintenance Key Points

Daily monitoring: Check outlet pressure (fluctuation ≤±0.05MPa), bearing temperature (≤70℃), and flow stability every 500 hours

Regular maintenance: Clean suction filters (precision ≤5mm) quarterly; replace lubricating oil (food-grade lubricating oil suitable for fresh water contact scenarios) every six months

In-depth maintenance: Conduct water pressure tests (1.5 times the rated pressure) every 6 years, inspect impeller wear (allowable deviation ≤0.5mm), and re-spray anti-corrosion coating

VI. Compliance and Certification

International standards: Complies with IMO SOLAS Convention Chapter II-1 and ISO 9906 pump performance testing specifications

Classification society certifications: Passed type approval for fresh water pumps by LR, ABS, CCS, and other institutions (including material, performance, and hygiene tests)

Hygiene certification: Flow-through components meet NSF/ANSI 61 standards for drinking water system components, ensuring water quality safety