What is heptafluoropropane fire extinguishing system

Although the NOVEC1230 fire extinguishing system has developed rapidly, the most popular system currently is still the heptafluoropropane fire extinguishing system FM200. Why is it so good? Let’s describe it in detail below.

BRIEF INTRODUCTION

Basic Properties

It is a modern intelligent automatic fire extinguishing device that integrates gas extinguishing, automatic control, and fire detection, The fire extinguishing agent HFC-227ea is a colorless, odorless, low toxicity, good insulation, and non-secondary pollution gas with zero ODP to the atmospheric ozone layer. It is halon 1211 and halon 1301 alternative.

Here are some of its benefits:

• It will not cause damage to property and precision facilities.
• Able to extinguish Class A, B, C, and electrical fires with a lower extinguishing concentration.
• Small storage space.
• High critical temperature.
• Low critical pressure.
• Liquefiable storage at room temperature.
• Free from particles and oil residue after release.
• The residence time in the atmosphere is 31 to 42 years, which meets international regulatory requirements.

It is CAS number is 431-89-0, The chemical molecular formula of heptafluoropropane HFC-227ea fire extinguishing agent is CF3CHFCF3.

Application

• Heptafluoropropane does not contain chlorine or bromine, will not have a destructive effect on the atmospheric ozone layer, It will not leave any residue or grease after release, It can also be discharged through normal exhaust channels, so it is very suitable as a fire extinguishing agent for data centers and server centers etc, Usually in these places heptafluoropropane fire extinguishing systems are installed, when a fire alarm occurs, heptafluoropropane is discharged from the tank, quickly draining the oxygen from the location of the fire and cooling the area to achieve the purpose of extinguishing the fire.
• Although heptafluoropropane is relatively stable at room temperature, it still decomposes at high temperatures and produces hydrogen fluoride, producing a pungent taste. Other combustion products include carbon monoxide and carbon dioxide.
• Contact with liquid heptafluoropropane can cause frostbite, so do not touch it unless necessary.
• The main extinguishing mechanism of heptafluoropropane is to cut off the combustion chain, with extremely fast fire extinguishing speed, this is beneficial for protecting electronic equipment and precision instruments.
• The non-toxic reaction concentration of heptafluoropropane is 9% (NOAEL=9%), and the toxic reaction concentration is 10.5% (LOAEL=10.5%), Its design concentration is generally less than 10%, which is safe for the human body, Its characteristic is good cleanliness (complete gasification in the atmosphere without leaving any residue).
• It has good gas-phase electrical insulation and good physical properties.

In the 1990s, developed countries such as Europe and America first replaced halon products with heptafluoropropane.

The heptafluoropropane fire extinguishing system cannot be used for fires involving the following substances

• Chemicals and mixtures of oxidants, such as sodium nitrate.
• Active metals, such as potassium, sodium, magnesium, aluminum, uranium, etc.
• Metallic oxide, potassium oxide, sodium oxide, etc.
• Chemicals with the ability to decompose on their own, such as hydrogen oxide and hydrazine, etc.

About the Heptafluoropropane Eire extinguishing System

Heptafluoropropane fire extinguishing devices contain two types: pipe network type and non-pipe network type.

Pipeline Network System

Its gas fire extinguishing agent storage bottles are usually placed in a dedicated steel room and connected through a pipeline network. In the event of a fire, the fire extinguishing agent is transported from the steel cylinder room to the protective area that needs to be extinguished and is sprayed through a nozzle to extinguish the fire.

System Composition

The heptafluoropropane gas fire extinguishing system includes fire extinguishing cylinder, high-pressure hose, check valve, pilot gas, selector valve, safety valve, pressure signal device (pressure switch), nozzle, high-pressure pipeline, etc.

• 1. Every fire extinguishing cylinder includes an agent storage cylinder, cylinder head control valve (container valve), Safety valve, manual valve, pressure gauge, Siphon, agent of heptafluoropropane, etc. Select different volumes of storage cylinders according to actual needs.
• 2. High-pressure hose is a device that connects fire extinguishers and one-way valves.
• 3. Between the high-pressure hose and the manifold there is a check valve. Its function is to prevent gas back-flow.
• 4. The pilot gas cylinder contains nitrogen gas,  When a fire occurs, the pilot gas cylinder receives instructions to activate the gas to open the selection valve and container valve and release the extinguishing agent.
• 5. The pilot gas cylinder includes a gas cylinder, bottle head control valve(container valve), electromagnetic starter, Check valve, safety valve, manual valve, Pressure gauge, and starting gas.
• 6. Use safety valves to prevent system overpressure.
• 7. Use the selector valve to control the entry of fire extinguishing agents into the corresponding protected area, In the case of multiple protected areas.
• 8. Selecting the corresponding size selector valve based on the calculated pipe diameter.
• 9. The pressure switch is a signal device transmitted to the fire control panel when the fire extinguishing system starts the spraying room, informing the host that the fire extinguishing agent is being sprayed.
• 10. The nozzle is the outlet channel of the fire extinguishing agent, used to spray the HFC-227ea agent.
• 11. Use High-pressure pipelines to transport fire extinguishing agents and serve as channels for extinguishing agents.
• 12. Use High-pressure pipe fittings to connect high-pressure pipelines.

Main Application Places

Pipeline network heptafluoropropane gas is suitable for Electronic computer rooms, libraries, archives, valuable items warehouses, power stations (transformer room), telecommunications centers, clean go, etc. Electronic computer room, library, archives, valuable items warehouse, power station (transformer room), telecommunications center, clean factories, etc.

Non-pipeline network system (Cabinet type heptafluoropropane fire extinguishing system)

This system uses a cabinet to package fire-extinguishing agent cylinders.

The cabinet has a beautiful appearance and is usually placed in a protected area.

In the event of a fire, it is not necessary to pass through the pipeline and directly spray and extinguish the fire in the protected area.

System Description

The pipe-less heptafluoropropane fire extinguishing system is a modern portable and mobile automatic fire extinguishing equipment, It has high fire extinguishing efficiency, fast fire extinguishing speed, low toxicity, no damage to equipment, excellent performance, and the control part can be connected to the fire control center.

Main Application Places

Computer room, server room, data center, library, transformer room, generator room, artwork gallery, museums, etc.

System Composition

Cabinet type FM200 fire suppression system contains the following components:

• Storage cylinder.
• Start-up device.
• Safety valve.
• pressure gauge.
• Cylinder cabinet.
• Spraying short pipe.
• Pressure gauge.
• The nozzle.
• The hfc-227ea agent.

Advantages and disadvantages of pipe network and non-pipe network systems

• The pipeline system is sprayed through the pipeline network, and the nozzles are evenly distributed, so the spraying is uniform and the fire extinguishing effect is good; However, non-pipe network systems are generally directly sprayed through the nozzles location at the top of the cabinet.
• We have to design the pipeline system with a separate cylinder room for storing extinguishing gas cylinders, which requires a pipeline network; The non-pipe network series does not require a gas cylinder room or a complex pipe network.
• If only protects one area, the cost of pipeline network one is higher; if protects multiple areas, the cost of non-piping network one is higher.
• The piping network type system has a steel cylinder room, which has a high pressure due to its relatively long distance. Generally, it is 4.2 Mpa and 5.6 Mpa, while the cabinet type system (pipe-less type) is in the protective zone, so the pressure should not be too high, usually at 2.5 Mpa.

Precautions

• When the concentration of heptafluoropropane exceeds 10%, the human body will feel uncomfortable, so the concentration of fire extinguishing agents is generally below 10%.
• Personnel should immediately stay away from the system during spraying.
• Choose a suitable location during installation to ensure good air circulation around the fire extinguishing device and facilitate gas discharge.
• Be careful not to allow direct sunlight during installation.
• Aim the nozzle of the device at the location where a fire may occur.
• Before use, Inspect the fire extinguishing device carefully to ensure its normal operation. Regularly check the gas pressure, discharge time, etc.

Summary

heptafluoropropane is one of the cleanest fire-extinguishing systems in the world, and its emergence has solved the problem of extinguishing fires in the vast majority of large spaces.

Its installation is quite complex, but its fire-extinguishing efficiency is also extremely high.