Fine water mist system nozzle

The water mist fire extinguishing system is composed of water supply device, water mist nozzle, control valve, filter device, water test valve and pipe network, among which the water mist nozzle is one of the very important components. There are many types of water mist system nozzles. Common ones include open water mist nozzles, closed water mist nozzles, high-pressure water mist nozzles, etc. The nozzles used in different water mist systems are different, and the specific nozzles should be selected according to the situation.

1. Selection of nozzles for fine water mist systems

1. For places where the nozzle holes of the nozzle are easily clogged by external foreign matter, a nozzle with corresponding protective measures that does not affect the spraying effect of fine water mist should be selected. For dusty places, a nozzle with a dust cover (end cover) should be used, but the water mist should not block the water mist and cause harm to personnel when spraying;

2. For the floor mezzanine of electronic data processing room and communication room, it is advisable to choose a sprinkler head suitable for low space;

3. For a closed system, a nozzle with a response time index no greater than 50 (m.s) 0.5 should be selected. Its nominal operating temperature should be 30°C higher than the maximum ambient temperature, and nozzles with the same thermal performance should be used in the same protection area;

4. For corrosive environments, nozzles made of anti-corrosion materials or anti-corrosion coatings should be used;

5. For water mist fire extinguishing systems in places with electrical fire hazards, it is not advisable to use impact atomization type water mist nozzles.

2. Spare quantity of nozzles for fine water mist system

Different water mist systems and different application sites have requirements not only for the type of water mist nozzles, but also for the number of water mist nozzles. For example, when purchasing water mist nozzles for engineering projects, the spare quantity of water mist nozzles must be taken into consideration in the design. There are clear requirements in this area.

Click to view:Spare quantity of water mist nozzles

3. Water mist system nozzle pressure

Water mist fire extinguishing systems are mainly divided into: ① low-pressure systems according to working pressure. The working pressure of the system distribution pipe network is less than or equal to 1.21 MPa. ② Medium pressure system, the working pressure of the system distribution pipe network is greater than 1. 21 MPa and less than 3.45 MPa. ③High-pressure system, the working pressure of the system distribution pipe network is greater than or equal to 3.45 MPa.

Click to view:What is the pressure of the water mist nozzle?

4. Installation of nozzles of fine water mist system

According to the type and height of the protected object, combined with the fine water mist specifications, and meeting the relevant intensity and spacing requirements of the spray, make a reasonable arrangement.

1. The maximum arrangement spacing of open water mist nozzles should not be greater than 4m. When the protected area area exceeds 500m2, zoning application should be adopted. For local application of water mist systems, the water mist should be sprayed directly onto the protected object, and its protected area should be determined based on its external surface area. When used outdoors, the impact of wind speed on water mist should be evaluated and the sprinkler heads should be appropriately enlarged.

2. When using a closed system, the number of nozzles controlled by the partition control valve shall not exceed 800, the functional area shall be determined according to 140m2, and the installation distance of nozzles shall not be greater than 3.5m and shall not be less than 2.0m. The distance between the temperature-sensing component of the closed sprinkler head and the top plate or bottom of the beam should be 75mm~150mm.

3. When used in partitions, public nozzles should be installed in adjacent parts. The spacing between nozzles should not be greater than 3m, and the spacing between rows should be 1.5~2.5m.

4. Except for local application systems, nozzles should be evenly arranged in a rectangular shape, and the distance between nozzles and walls or horizontal obstacles should not be greater than half of the maximum spacing between nozzles.

There are three main types of water mist fire extinguishing systems: high pressure water mist fire extinguishing systems, medium pressure water mist fire extinguishing systems and low pressure water mist fire extinguishing systems. High pressure water mist fire extinguishing systems are more widely used. The nozzles used include high pressure water mist open nozzles and high pressure water mist closed nozzles. There are many models of water mist system nozzles, and customers can also customize them according to their own needs. Anhui Lanzhong Electromechanical can provide customization, processing, after-sales and other services to meet the requirements of different customers.

More information on water mist nozzles:

How to clean the fine water mist nozzle

How much does a fine water mist nozzle cost?

Is the water mist nozzle open or closed?

Spare quantity of water mist nozzles

Which is better, fine water mist nozzle or water mist nozzle?