What is the pressure of the water mist nozzle?

There are many parameters for water mist nozzles, such as material, interface size, flow rate, working pressure, spray angle, range, structural type, etc. Among them, working pressure is one of the very important performance parameters of water mist nozzles. So what is the pressure of the water mist nozzle? There are many working pressures of fine water mist nozzles, such as 1.2Mpa, 3.5Mpa, 10Mpa, etc. Customers can usually choose or customize according to their own application needs.

1. Pressure range of water mist nozzle

1. The minimum working pressure of the single-fluid water mist nozzle should be selected from the 1.2MPa, 1.5MPa, 2.0MPa, 3.0MPa, 3.5MPa, 4.0MPa, 5.0MPa, 6.0MPa, 8.0MPa, and 10.0MPa series.

2. The manufacturer should specify and clearly indicate the maximum working pressure, storage pressure of the device and the allowable working pressure range of the water mist nozzle.

3. The gas storage pressure of the bottle-type water mist device and the maximum working pressure of the device should comply with the provisions of Table 2 (when the storage gas is nitrogen).

2. High pressure water mist nozzle pressure

Working pressure of high-pressure water mist nozzle: P≥3.5MPa

Generally, high-pressure water mist refers to water mist with DV0.99<100μm produced under a pressure of not less than 10MPa. The working pressure of the high-pressure water mist fire extinguishing system is greater than 10MPa. It is based on a positive displacement pump. A plunger pump is usually used, and the system pressure can reach as high as 100-200MPa.

The nozzle flow coefficient of the high-pressure water mist fire extinguishing system is low and the water damage loss is small. It can be used in places with higher requirements such as computer rooms, archives rooms, and cultural relics libraries. Therefore, most of the water mist fire extinguishing systems we currently use are high-pressure water mist fire extinguishing systems with a nozzle working pressure of not less than 10MPa.

3. Medium pressure water mist nozzle pressure

Medium pressure water mist nozzle working pressure: 1.20MPa≤P<3.50MPa

The working pressure of medium-pressure water mist fire extinguishing systems is between 1.2MPa and 3.5MPa. Generally, fire pumps greater than 2.0MPa will use plunger pumps. The purchase and maintenance costs of plunger pumps are higher than centrifugal pumps. Although the droplet size has been reduced, it still cannot achieve the ideal effect. Therefore, medium-pressure water mist is also not widely used.

4. Low pressure water mist nozzle pressure

Working pressure of low-pressure water mist nozzle: P<1.20MPa

The working pressure of the low-pressure water mist fire extinguishing system is less than 1.2MPa, and a conventional fire centrifugal pump unit can meet the requirements. The low-pressure water mist fire extinguishing system is similar to the water spray fire extinguishing system, except that the pipes are required to use austenitic stainless steel pipes, and the nozzle structure is also different (such as a finer spray aperture).

The droplet size of the low-pressure water mist fire extinguishing system is relatively large, the flow coefficient of the nozzle is high, it requires more water, and the impact of water damage is also great. Therefore, the low-pressure water mist fire extinguishing system is generally used in diesel generator rooms, oil-immersed transformers, cable tunnels, cable mezzanines, fuel-fired boiler rooms and other places where water spray is commonly used.

The protection objects of low-pressure water mist fire extinguishing systems are not much different from those of water spray fire extinguishing systems, and they also require more water consumption. However, the cost of low-pressure water mist fire extinguishing systems is much higher than that of water spray systems. In particular, the sprinkler heads have high requirements for water quality, and the future operation and maintenance costs are also high. Therefore, people generally do not choose low-pressure water mist fire extinguishing systems.

5. Customization of fine water mist nozzles

The working pressure of water mist nozzles is not fixed. In different scenarios, the working pressure of the system is different, so most of the time the water mist nozzles need to be customized according to the pressure. Anhui Lanzhong Electromechanical has the ability to design and produce various forms of fine water mist nozzles, and can customize the structural type, flow coefficient and material according to customer needs. Customer customization requires at least the following information:

(1) Nozzle (nozzle) structural type, such as appearance size, thread, structure, etc.;

(2) Medium;

(3) Flow coefficient;

(4) Performance requirements, such as droplet diameter, range, spray angle, installation parameters, etc.;

(5) Minimum and maximum working pressure;

(6) Application site and working environment;

(7) Material;

(8) The closed nozzle should also provide glass ball parameters.

Fine water mist nozzles have been widely used in many scenarios, such as libraries, archives, ancient buildings, computer rooms, power distribution rooms and other places. Water mist nozzles are used in different scenarios, and the working pressure is different. When choosing a water mist nozzle, customers also need to clarify the working pressure of the system, so that they can buy a more suitable nozzle and better play the role of the water mist nozzle.