Breathing valves are mainly used in atmospheric and low-pressure storage tanks (such as HCL / HNO3 storage tanks) that contain certain volatile chemical substances that are not allowed to leak. Ensure that the pressure in the tank is in a normal state, prevent the storage tank from being damaged by the positive and negative pressure in the tank, and reduce the volatilization loss of the liquid in the tank.
Breathing valve is also called "German type". The main feature of zui is its large ventilation capacity, which is suitable for large-capacity storage tanks and highly volatile media. The valve discs are not connected to each other), suitable for use in cold regions such as Northeast and Northwest to improve the safety factor of storage tanks. Make full use of the pressure capacity of the storage tank to reduce the discharge of the medium. The principle is to use the weight of the positive and negative pressure valve discs to control the positive pressure of the exhaust tank and the negative pressure of the suction tank. When the pressure of the medium in the tank is within the control operating pressure range, it will not work and maintain the tightness of the oil tank; when the medium is replenished to the tank, the pressure in the upper gas space in the tank will rise, and when the positive operating pressure is reached, The pressure valve is pushed open, and the gas escapes from the exhalation port, so that the pressure inside the tank does not continue to increase; when the medium is drawn out of the tank, the pressure in the upper gas space inside the tank drops, and when the operating negative pressure is reached, the atmosphere outside the tank will top out. Open the negative pressure valve disc to open up, so that outside air can enter the tank, so that the pressure in the tank can no longer continue to drop, and the air pressure inside the tank and the tank can be balanced to protect the safety device of the storage tank.
|ZFQ-88 / 89 (fire resistance) technical parameters||Size mm|
|The main material||Carbon steel aluminum alloy 304 316L||specification||H||L|
|Fire-resistant core pieces||304 316L||DN50||320||320|
|Positive valve disc||304 316L aluminum alloy||DN80||370||400|
|Negative valve disc||304 316L PTFE||DN100||380||420|
|Bolts and nuts||20 # 304 316L||DN200||520||600|
|Explosion-proof grade||BS 5501: ⅡA BC||DN250||600||680|
|Operating pressure||+ 9800Pa ~ -600Pa||DN300||650||750|
|Flange standard||GB HG JIS ANSI DIN||DN350||700||850|
Note: The above product pictures and data are for reference only. For accurate drawings, please consult.
1. In order to use it safely, the corrugated fire barrier should be removed and cleaned regularly within 3-6 months to ensure that each hole in the fire barrier is unblocked to prevent blockage and ensure safe and normal use. Regularly check whether the positive and negative valve discs are ventilated flexibly and whether the contact surfaces of the guide rods and valve discs are damaged. Replace them immediately if damaged. When inspecting, maintaining and reinstalling, it is necessary to ensure that the joint surfaces in the valve are closely matched, and the valve disc is flexible to lift. When the new valve is activated, the flange protection cover should be removed before installation, and the anti-vibration between the valve discs should be removed, otherwise it will fail.
2. It should be installed at the high point of the tank gas source to reduce the evaporation loss of the material and to provide a smooth and direct channel to the zui. Generally, vertical tanks should be installed within the range of the central roof of the tank roof. For storage tanks with a thermal insulation layer on the tank roof, they can be installed near the ladder platform.
3. At the time of shipment, our company added dust protection caps to the flange surface. Be sure to remove the dust protection caps when installing. When two are required to be installed, they should be arranged symmetrically with the center of the tank top. When loading and unloading, it must be vertical upwards, and not upside down or horizontally. When removing and cleaning the valve stem, it should be placed vertically and gently, otherwise, the valve stem is easily deformed.
4. If used on a nitrogen-sealed tank, the takeover position of the nitrogen gas supply pipe should be away from the interface, and inserted into the storage tank about 200mm from the top of the tank, so that the nitrogen is not directly discharged after entering the tank, and the purpose of nitrogen sealing is achieved.