High-pressure fine water mist stainless steel pipeline

The high-pressure fine water mist stainless steel pipeline system is an advanced fire protection solution that combines high-pressure fine water mist fire suppression technology with corrosion-resistant pipeline materials. It is widely used in data centers, rail transit, ships, power facilities, archives, and other places with high requirements for fire suppression efficiency, environmental safety, and equipment durability. Here are its core points and technical explanations: 

1. Specifications of commonly used high-pressure fine water mist fire protection stainless steel seamless pipes:

(As shown in Figure 1) 

II. System Overview

High-pressure fine water mist (Hi-Fog):

By applying high pressure (typically ≥ 10 MPa), water is atomized into fine water droplets with diameters ranging from 10 to 100 micrometers. It features efficient fire suppression, cooling, smoke suppression, and reduction of water damage.

Stainless steel pipeline:

Made of 304/316 stainless steel, it is corrosion-resistant and has high strength, enabling long-term stable operation in complex environments. 

III. Advantages of Stainless Steel Pipes 

Corrosion Resistance:

316 stainless steel contains molybdenum, which has a stronger resistance to chloride ion corrosion and is suitable for high-corrosion environments such as coastal areas and chemical zones.

Pressure-bearing Capacity:

The yield strength of stainless steel is high (for example, 316L is approximately 205 MPa), enabling it to withstand high system pressure (typically 20-35 MPa), thus avoiding the risk of rupture.

Hygiene and Environmental Protection:

It does not release harmful substances and complies with hygiene requirements for food, medical, and other places.

Long Service Life:

Resistant to rust and wear, with low maintenance costs, and the design life can reach over 30 years. 

IV. System Composition and Design Key Points 

Core Components:

Pump Set:

Provide continuous high pressure of ≥ 10 MPa (centrifugal pump or piston pump).

Stainless Steel Pipeline Network:

Main pipelines (DN50-DN200), branch pipes, valves, flanges, etc.

Fine Water Mist Nozzles:

Special atomizing nozzles, covering evenly and responding quickly.

Control System:

Automatic/Manual Trigger, linked to the fire alarm system.

Design Parameters:

Working Pressure:

Usually 10-35 MPa (adjusted according to nozzle type and protection area requirements).

Flow Calculation:

Determined based on the volume of the protected area, hazard level (NFPA 750/GB 50898 standards).

Pipeline Layout:

Ring or branch network layout to ensure pressure balance and rapid response. 

V. Installation and Construction Precautions 

Material selection:

316 stainless steel is preferred, especially in high salt spray and acidic environments.

The pipe wall thickness should be calculated based on the pressure (for example, a wall thickness of 40 for SCH40). Connection method:

Welding:

Argon arc welding ensures sealing and prevents intergranular corrosion.

Flange/Socket connection:

Easy for maintenance, but requires strict sealing treatment.

Construction specifications:

Clean the interior of the pipeline to avoid residual welding slag and rust.

Avoid mechanical scratches or excessive bending to prevent stress concentration.

Install sleeves at wall/ceiling penetrations to prevent vibration and mechanical damage. 

VI. Maintenance and Management 

Water quality control:

Regularly filter and soften the water source to prevent impurities from clogging the nozzles or corroding the pipes.

Leak detection:

Regularly inspect welds and flange connections, using leak detection fluid or ultrasonic testing equipment.

Pressure test:

Conduct a static pressure/dynamic pressure test once a year to ensure the reliability of the system.

Nozzle maintenance:

Clean obstructions, check the atomization effect, and replace if necessary. 

VII. Application Scenario Examples 

Data Center:

Pollution-free fire suppression, protecting server equipment.

Ship Engine Room:

Resistant to salt spray corrosion, meeting SOLAS regulations.

Rail Transit:

Quick fire control in tunnels and subway stations, reducing obstacles to escape.

Ancient Buildings/Museums:

Minimal water usage, maximizing protection of cultural relics. 

VIII. Relevant Standards and Certifications 

International standards:

NFPA 750 (Fine Water Mist Fire Extinguishing System), ISO 14520 (Gas Fire Extinguishing System).

Domestic standards:

GB 50898 "Technical Specifications for Fine Water Mist Fire Extinguishing System".

Material certification:

ASTM A240 (Stainless Steel Sheet), WRAS (British Water Certification), etc. 

IX. Common Issues and Solutions 

Nozzle blockage:

Install a pre-filter and regularly clean the pipes.

Pipe corrosion:

Choose high-grade stainless steel (such as 316L) and avoid contact with chlorine-containing media.

Unstable pressure:

Check the pressure maintenance device of the water pump and ensure the stable operation of the pressure stabilizing pump.