Impact type water mist nozzle is a common type of water mist nozzle. It refers to a nozzle that decomposes water flow into water droplets with Dv0.9 less than 1mm under a certain water pressure and sprays it according to the designed sprinkler shape. Impact-type water mist nozzles are also called medium-speed water mist nozzles. Their model is ZSTWC. They are commonly used to protect flammable liquid storage tanks and flammable gas storage tanks.

Impact type water mist nozzle specifications:

● Atomization angle: 45°, 60°, 90°, 120°, 150° (for water mist nozzles of foam spray fire extinguishing systems, the atomization angle should not be greater than 90°)

● Working pressure: 0.35Mpa and above

● Nozzle material: stainless steel 304, 316, copper, etc.

● Water droplet diameter: Dv0.9~900μm

● Product standards: Made in strict accordance with relevant standards for water mist nozzles

Impact water mist nozzle working pressure:

Water mist nozzles must be under a certain pressure to function effectively. The working pressure of the water mist nozzle must meet the following requirements: the working pressure of the water mist nozzle should not be less than 0.35MPa when used for fire extinguishing; when used for protective cooling, it should not be less than 0.2MPa, but for Class A, B, B, and C liquid storage tanks, it should not be less than 0.15MPa.

Impact water mist nozzles are suitable for:

It is usually used to protect hazardous areas of liquids, flammable gases and solids with flash points below 66°C. It can also be used as a nozzle for foam systems. Such as: liquefied petroleum gas, liquefied natural gas or oil tanks, etc.

● Factory fire prevention and fire extinguishing

● Shopping mall fire fighting

● Warehouse fire control and extinguishing

●Quickly extinguish fire in liquefied gas tank

● Oil storage tank fire prevention

Working principle of impact type water mist nozzle:

The pressure water flow from the impact type water mist nozzle passes through the external splash plate and is dispersed into a uniform cone-shaped water mist in the set area. The nozzle consists of a splash plate, a diverter cone, a frame body and a filter. Impact water mist nozzles can be installed horizontally, drooping, or diagonally as needed.

The difference between impact type water mist nozzles and centrifugal water mist nozzles:

Centrifugal atomization: When the water flow enters the nozzle, it is decomposed into a rotating water flow with centrifugal speed moving along the inner wall and a straight water flow with axial speed. The two water flows merge in the nozzle and are then ejected from the nozzle at their combined speed to form atomization.

Impact atomization: The water flow collides with the splash plate to form atomization.

Water mist nozzle selection requirements:

1. To fight electrical fires, centrifugal atomization water mist nozzles should be used;

Note: The mist water droplets ejected by the centrifugal atomization nozzle are discontinuous intermittent water droplets. They have good electrical insulation properties and can effectively extinguish electrical fires. They are suitable for use in water spray fire extinguishing systems that protect electrical facilities. Impact-type water mist nozzles use the impact principle to decompose water flow. The degree of atomization of water is poor and the electrical insulation performance of mist water cannot be confirmed, so it is not suitable for fighting electrical fires.

2. Water mist nozzles installed in indoor dusty places should wear dust-proof caps, and water mist nozzles installed outdoors should wear dust-proof caps;

Note: Most water mist nozzles are equipped with an atomizing core inside, and the cross-sectional area of ​​the internal effective water flow channel is small. If exposed to dust for a long time, the internal water flow channel is easily blocked, so it is required to wear a dust cap. Normally, the dust cap is on the nozzle of the water mist nozzle. In the event of a fire, the dust cap will open or fall off under the action of water pressure, which will not affect the normal operation of the water mist nozzle.

3. The centrifugal atomization water mist nozzle should be equipped with a columnar filter.

Note: To prevent nozzle clogging, centrifugal atomization water mist nozzles need to be equipped with a columnar filter.