Marine Steel Cast Ejector Fresh Water Pump

I. Product Overview

The marine steel cast ejector fresh water pump is a core key equipment of the ship's fresh water supply system. It is specially designed for scenarios such as ship fresh water transfer, seawater desalination supply, cooling water circulation, domestic water supply and emergency fresh water guarantee. Its core working principle is to form negative pressure suction through the high-speed ejector of the injector to achieve efficient suction and pressure-boosted delivery of fresh water. Relying on the unique ejector structure and the high-strength characteristics of the steel cast material, it can stably complete the precise delivery of various fresh water resources, ensuring the continuous realization of key needs such as ship power system cooling, crew domestic water supply and emergency fresh water supply.

The core components of the equipment (pump body, injector, impeller, base) are all integrally cast with high-quality steel cast, matched with temperature-resistant and corrosion-resistant sealing components and reinforced transmission shafts. It has core characteristics such as compact structure, high strength and impact resistance, corrosion resistance and salt spray resistance, strong self-priming capacity, and stable and reliable operation, which can easily adapt to complex marine working conditions such as high humidity, strong salt spray, severe vibration and large temperature difference fluctuations faced by ocean-going and coastal ships. As the "core hub" for the transportation of fresh water resources on ships, the product strictly complies with international and domestic standards such as the International Convention for the Safety of Life at Sea (SOLAS), IMO Marine Machinery Equipment Rules, GB/T 10832-2011 *Marine Pumps* and GB/T 6245-2019 *Fire Pumps*. It has obtained certifications from mainstream classification societies such as China Classification Society (CCS) and American Bureau of Shipping (ABS), and is widely used in various ships including 500-200000 ton ocean-going cargo ships, oil tankers, container ships, bulk carriers, ro-ro passenger ships and offshore operation platforms. Compared with cast iron fresh water pumps, steel cast material has significant advantages in strength, corrosion resistance and service life, especially suitable for harsh working conditions of medium and large ships and long-term ocean-going navigation, and has become the preferred equipment for fresh water systems of medium and large ships.

II. Core Technical Parameters

Pressure Range: Rated working pressure 0.3-1.6 MPa, maximum working pressure up to 2.0 MPa, pressure fluctuation error ≤ ±1.2%. It can meet the pressure requirements for long-distance transportation of fresh water on ships, water supply for multi-layer cabins and pressure-boosted circulation, ensuring stable and controllable water supply pressure.

Flow Range: 5-200 m³/h, which can be customized in grades according to ship tonnage (500-200000 tons) and fresh water demand (number of crew, equipment cooling demand). The flow stability error under rated working conditions is ≤ ±2%, adapting to the fresh water transportation needs of ships of different scales.

Medium Adaptability: Designed specifically for fresh water transportation, it can stably transport ship domestic fresh water, cooling fresh water, fresh water produced by seawater desalination, etc.; suitable for medium viscosity range 1-5 mm²/s, impurity content ≤ 0.1% (particle size ≤ 1mm); applicable medium temperature range -5℃ to 80℃, which can cope with navigation in low-temperature sea areas and medium-high temperature fresh water transportation working conditions of equipment cooling circulation.

III. Structural Design and Core Advantages

3.1 Core Structural Design

Efficient ejector Pressure-Boosted Structure: Adopts integrated injector design, forming strong negative pressure suction through high-speed fluid ejector, greatly improving self-priming capacity, and can start quickly without additional priming water; the ejector channel is optimized through fluid mechanics to reduce water flow resistance, realize efficient pressure-boosted transportation of fresh water, and improve water supply efficiency.

Integral Steel Cast Molding Structure: The pump body and base are formed by integral casting process, without splicing welds, with compact and solid structure and tensile strength ≥ 450 MPa, which can withstand the bumpy impact during ship navigation and pressure fluctuation during fresh water transportation; the steel cast material has excellent thermal conductivity, which can assist in reducing the operating temperature of the pump body and extending the service life of the equipment.

Enhanced Sealing Protection System: Adopts "mechanical seal + oil seal" double sealing structure, the sealing surface is made of alumina-graphite composite material, and the seal lip structure is optimized according to the characteristics of fresh water transportation, effectively preventing fresh water leakage and external impurity intrusion; equipped with a moisture-proof device in the seal chamber, adapting to the high humidity environment of the ship, avoiding moisture damage to the seal components.

3.2 Core Technical Advantages

High Strength and Corrosion Resistance, Adapting to Marine Working Conditions: Steel cast material has excellent tensile strength and corrosion resistance. After double anti-rust treatment, it can effectively resist the erosion of high salt spray and high humidity environment of ships, and is not easy to rust and deform; compared with cast iron fresh water pumps, the service life is extended by more than 50%, suitable for harsh needs of medium and large ships for long-term ocean-going navigation.

Strong Self-Priming Capacity, Convenient Start-Up: The unique ejector structure enables the self-priming height to reach 5.0 m, far exceeding that of conventional centrifugal pumps. No additional priming device is needed, and it can start quickly in scenarios such as emergency water supply and water intake in shallow water areas, ensuring uninterrupted fresh water supply; the short self-priming time greatly improves emergency response efficiency.

Stable and Reliable Operation, Precise Water Supply: The ejector structure has no pulsation and small vibration during operation, and can stably output fresh water with constant pressure and flow, avoiding failures of the ship's cooling system and domestic water supply system caused by pressure fluctuations; there are few core moving parts and few fault points, adapting to complex vibration working conditions of ships, with high operational reliability.

Convenient Maintenance and Simple Operation: Key components adopt modular design. Wearing parts such as injectors and seals can be quickly disassembled and replaced with simple tools without overall disassembly of the pump body; daily maintenance only needs to regularly check fresh water cleanliness, clean the inlet filter screen and supplement lubricating oil, with a long maintenance cycle (regular maintenance interval ≥ 8 months), reducing the maintenance workload of the crew.

Safe and Compliant, Wide Adaptability: Strictly complies with international and domestic ship safety and fresh water transportation equipment standards, and has passed multiple rigorous tests by classification societies such as pressure test, leakage test, vibration test and salt spray corrosion test; adapts to the fresh water systems of various 500-200000 ton ships, and can be simply customized according to the ship's fresh water demand and navigation working conditions, with strong adaptability.

IV. Typical Application Scenarios

4.1 Fresh Water Supply for Ship Seawater Desalination System

Seawater desalination is the core way for ocean-going ships to obtain fresh water resources, which has high requirements for the self-priming capacity and stability of the supply pump. Relying on the strong self-priming capacity of ≥ 5.0 m, the marine steel cast ejector fresh water pump can quickly suck the fresh water produced by the seawater desalination equipment and transport it to the fresh water storage tank; the stable flow output ensures the supply efficiency and avoids fluctuations in the water level of the storage tank; the steel cast material has strong corrosion resistance, adapts to the high salt spray environment on the ship deck, and has no rust during long-term operation.

4.2 Cooling Water Circulation of Ship Main Engine/Auxiliary Engine

A large amount of fresh water circulation cooling is required during the operation of the ship's main engine and auxiliary engine, which has strict requirements for the pressure stability and heat dissipation of the pump. The rated working pressure of the marine steel cast ejector fresh water pump is 0.3-1.6 MPa, which can accurately match the pressure demand of the cooling system and ensure the smooth circulation of cooling water; the steel cast material has excellent thermal conductivity, which can assist in reducing the operating temperature of the pump body and avoiding equipment failures under high-temperature working conditions; low vibration operation does not affect the working environment of the power equipment, ensuring the stable operation of the power system.

4.3 Ship Domestic Fresh Water Transportation

Crew domestic water (washing, drinking, kitchen water) requires clean and stable fresh water supply. The marine steel cast ejector fresh water pump has a flow stability error of ≤ ±2%, which can accurately control the supply of domestic water and avoid sudden changes in water pressure; the sealing components have no leakage and no pollution, ensuring the safety of fresh water quality; the operating noise is ≤ 72 dB(A), which does not affect the crew's living environment, adapting to the living needs of long-term ocean-going ships.

4.4 Ship Deck Washing and Emergency Water Supply

Ship deck washing, equipment cleaning and emergency fire fighting (fresh water auxiliary) require convenient and efficient water supply equipment. The marine steel cast ejector fresh water pump starts quickly and has strong self-priming capacity, which can quickly respond to deck washing needs; it has overload and pressure abnormality protection functions, and can operate stably in emergency water supply scenarios to ensure the smooth development of emergency operations; the steel cast material has strong impact resistance, adapting to the complex environment of open-air operations on the deck.

4.5 Fresh Water Supply for Offshore Operation Platforms

Offshore operation platforms such as offshore drilling platforms and wind power platforms are scarce in fresh water resources, which have extremely high requirements for the corrosion resistance and reliability of water supply equipment. The marine steel cast ejector fresh water pump can adapt to the harsh environment of high salt spray and strong wind and waves on the platform, and stably complete the transfer and supply of fresh water; the continuous operation life is ≥ 12000 hours, supporting 24-hour uninterrupted water supply, meeting the fresh water needs of platform operators' life and equipment operation.