20 17 first-class fire engineer's knowledge: foam generator installation

I'll sort out "20 17 Knowledge Points for First-class Fire Engineers: Installation of Foam Generating Devices" for you. Hehe, welcome all netizens to learn, I hope it will help you! For more information, please pay attention to this website update!

1. Installation of low multiple foam generator

1) Installation requirements:

① The liquid jet foam generator shall be installed according to the type of the generator and meet the design requirements. There are two kinds of spray foam generators on liquid: horizontal and vertical. The specific objects are shown in Figure 3-8-8. The horizontal foam generator should be installed horizontally on the foam guide plate at the top of the fixed roof tank wall or the top of the external floating roof tank wall. The vertical foam generator should be installed vertically on the foam deflector at the top of the fixed roof tank wall or the top of the external floating roof tank wall.

② The foam chute in the water-soluble liquid storage tank should be spirally installed along the inner side of the tank wall to a distance of 1.0 ~ 1.5m from the tank bottom, and the included angle between the chute and the tank bottom plane is generally 300 ~ 45. The foam settling tank shall be installed vertically, and the allowable deviation of verticality shall be 5‰ of the height of the settling tank and not more than 30mm, the allowable deviation of coordinates shall be 25mm, and the allowable deviation of elevation shall be 20mm. ③ The foam generator with high back pressure sprayed under liquid and semi-liquid should be installed horizontally on the foam mixture pipeline outside the fire dike.

④ The pressure gauge interface arranged at the inlet side of the high back pressure foam generator should be installed vertically; The installation dimensions of outlet pressure gauge, back pressure regulating valve and foam sampling port shall meet the design requirements. In the area where the ambient temperature is lower than 0℃, the back pressure regulating valve and the control valve at the foam sampling port should adopt steel valves.

⑤ When the foam generator or foam guide cover is uniformly arranged around the tank, the spacing deviation is generally not greater than100 mm.. ⑤ When the foam nozzle of the external floating roof storage tank is arranged on the floating roof, the foam mixed liquid branch pipe should be fixed on the bracket, and the horizontal pipe of the T-shaped pipe of the foam nozzle should be installed horizontally, and it will be inclined downward by 30 after extending into the foam weir plate. ~60? .

⑦ When the foam nozzle of the external floating roof storage tank is set at the top of the tank wall, above the sealing or flashing board or below the metal flashing board, the height of the foam weir board and the distance from the tank wall should meet the design requirements. Among them, when the foam injection port is set at the top of the tank wall, above the seal or flooding, the foam weir plate should be more than 0.2m higher than the seal; when the foam injection port is set at the lower part of the metal flooding, the height of the foam weir plate should be not less than 0.3m, and the distance between the foam weir plate and the tank wall should be more than 0.6m.. ⑧ The number and size of drainage holes at the bottom of foam weir plate should meet the design requirements and be evenly distributed along the circumference of foam weir plate. The distance deviation should not be greater than 20mm, in which the opening area of the drainage hole is determined according to the annular area 1㎡ 280m㎡, and the height of the drainage hole is not greater than 9mm⑨ The height of the foam weir plate and the distance from the tank wall of single and double-disk floating roof storage tanks should meet the design requirements. The distance between the foam weir plate and the tank wall should not be less than 0.55m, and the height of the foam weir plate should not be less than 0.5m Note: When the foam generator with high back pressure required by the storage tank is installed in parallel, it should be fixed on the bracket in parallel and meet the requirements of items 3 and 4.

In addition, the semi-submersible foam spraying device needs to be installed on the horizontal pipeline between the steel open-stem gate valve and the check valve group where the foam pipeline enters the storage tank, and connected with the check valve through an expander (telescopic device) or a metal hose. During installation, the sealing membrane and its accessories cannot be disassembled or damaged.

2) Detection method: visual inspection and ruler inspection.

2. Installation of medium-sized multiple foam generator

1) installation requirements: the installation of the medium multiple foam generator shall meet the design requirements, and the accessories shall not be damaged or disassembled at will during the installation. 2) Detection method: Measure, observe and check with a stay wire and a ruler.

3. Install the high expansion foam generator

1) Installation requirements:

① The high-power foam generator should be installed above the submerged depth of foam, as close as possible to the protected object, but it should not be affected by explosion or flame. At the same time, the installation should ensure that it is easy to form a uniform foam coating in the protected area.

② The high-expansion foam generator is powered by rotating blades to blow air, so that a large amount of air flow enters the generator from the air inlet, so there can be no obstacles affecting the air flow within a certain range of the air inlet. Generally speaking, it is necessary to ensure that there are no obstacles at a distance less than or equal to 0.3m from the air inlet end of the high expansion foam generator.

(3) There should be no obstacles affecting foam injection at the position less than or equal to 1.0m in front of the foam screen of the high-power foam generator.

④ The high-power foam generator shall be installed as a whole and shall not be disassembled. In addition, because the blade is driven by the power source to rotate at high speed, if it is not fixed firmly, the high-expansion foam generator will vibrate and deviate. Therefore, the high expansion foam generator must be firmly installed on buildings and structures.

⑤ When the foam generator is used outdoors or in a tunnel, measures should be taken to prevent the wind from affecting the foam generator and foam distribution. The entity of high multiple foam generator is shown in Figure 3-8- 12. According to the different prime movers that drive the blades, the high-multiple foam generator can be divided into electric type and hydraulic type. The electric high-multiple foam generator has a high foaming multiple, generally more than 600 times, and the foaming amount is between 200m3/min and 200m3/min. Because the motor is not fire-resistant, it is generally not recommended to install an electric high-expansion foam generator in the protected area.

The foaming multiple of hydraulic high-expansion foam generator is low, generally 200 ~ 800 times; The foaming capacity range is relatively small, generally 40 ~ 400 m3/min. The hydraulic high expansion foam generator has a wide range of applications, which can be foamed with fresh air or hot flue gas, and can be installed in the protected area of the system.

2) Detection method: straightedge inspection and observation inspection.

4. Installation of foam nozzle

1) Installation requirements:

(1) the specifications and models of the foam nozzle are closely related to the type of foam liquid, the supply intensity of foam mixed liquid and the protection area, which shall not be misplaced and must meet the design requirements; Moreover, the installation of foam nozzle should be carried out after the system pressure test and flushing are qualified, because the aperture of foam nozzle is small, the system pipeline is not cleaned cleanly, and foreign objects are easy to block the nozzle, which affects the foam fire extinguishing effect. The physical object of the air-breathing foam nozzle is shown in Figure 3-8- 13.

(2) The foam nozzle shall be installed firmly and neatly, and the accessories on the nozzle shall not be disassembled or damaged during installation.

(3) The top-mounted foam nozzle should be installed on the upper part of the protected object, and the allowable deviation of its coordinates is 15mm for outdoor installation and10 mm for indoor installation; The allowable deviation of outdoor installation elevation is 15mm, and the allowable deviation of indoor installation elevation is10 mm. (4) The foam sprinkler installed horizontally should be installed on the side of the protected object and aimed at the protected object, and the allowable deviation of the distance is 20mm(2) Detection method: ruler measurement and observation inspection.

5. Install the fixed foam gun

1) Installation requirements:

(1) The riser of the fixed foam gun should be installed vertically, the muzzle should face the protected area, and there should be no obstacles that affect foam injection. (2) The foam gun installed on the turret or bracket shall be firmly fixed. The inlet pressure of the fixed foam gun is generally above 1.0MPa, and the flow rate is also large, so the fixed foam gun installed on the turret or bracket should be fixed firmly.

(3) The specifications, models, setting positions, laying methods and wiring of the control equipment, power cord and control line of the electric foam gun should meet the design requirements.

2) Detection method: observation and inspection.