Tank breathing valve is a component installed on the top of the tank, which is mainly used to meet the ventilation requirements of large and small breathing of the tank and is an important accessory to protect the safety of the tank.
Storage tanks are generally composed of pressure valves and vacuum valves. Its function is to keep the storage tank airtight and reduce the evaporation loss of stored substances in the storage tank to some extent. When necessary, it can automatically ventilate, adjust and balance the internal and external pressure of the storage tank, and play a safe role in the storage tank.
Secondly, there are several kinds of storage tank breathing valves.
There are many types of storage tank breathing valves, which are roughly as follows:
1, tight breathing valve
Tight breathing valve is usually used in low-pressure straight-through pipeline, its sealing performance depends entirely on the cooperation between plug and plug body, and the compression of its sealing surface is realized by tightening the nut at the lower part. Generally used for PN≤0.6Mpa.
2, packing type breathing valve
The packing type breathing valve realizes the sealing between the plug and the plug body by pressing the packing. Due to the filler, the sealing performance is good. Usually, this kind of breathing valve has a packing gland, and the plug does not need to extend out of the valve body, thus reducing the leakage path of the working medium. This breathing valve is widely used in situations where the pressure pn is less than or equal to1MPa.
3. Self-sealing breathing valve
The self-sealing breathing valve realizes the tight seal between the valve core and the valve core body through the pressure of the medium itself. The small head of the plug extends upward out of the valve body, and the medium enters the big head of the plug through the small hole at the entrance, squeezing the plug upward. This structure is generally used for air medium.
4. Oil seal breathing valve
Now the application scope of breathing valve is expanding, and the forced lubrication oil seal breathing valve appears. Due to forced lubrication, an oil film is formed between the sealing surface of the valve plug and the valve plug body. In this way, the sealing performance is better, opening and closing are more labor-saving, and the sealing surface is prevented from being damaged.
3. What is the working principle of the storage tank breathing valve?
The working principle of storage tank breathing valve is simple:
When the pressure of the medium in the tank is within the controlled working pressure range of the breathing valve, the breathing valve does not work to keep the tank sealed; When the medium is added to the tank, the pressure in the upper gas space in the tank increases to the working positive pressure of the breathing valve, the pressure valve is pushed open, and the gas escapes from the outlet of the breathing valve, so that the pressure in the tank does not continue to increase; The atmosphere outside the tank will push open the negative pressure valve disc of the breathing valve to isolate the space inside the tank from the atmosphere, thus protecting the safety of the tank.