Brief analysis of the working principle of the position breathing valve

Brief analysis of the working principle of the position breathing valve

The level breathing valve is a ventilation device fixed on the top of the tank to ensure the normal pressure in the tank, prevent overpressure or vacuum in the tank from damaging the tank, and the water level switch   Level Switch   It also reduces the loss of liquid volatilization in the tank. The breathing valve not only maintains the pressure balance of the tank, ensures that the tank is destroyed during overpressure or vacuum, and can reduce the media and losses in the tank.

The working principle of the level breathing valve is to use the spring limit valve plate , which is determined by positive and negative pressure or call or suction . The breathing valve should have two functions of positive and negative pressure relief, specifically: when the container is under positive pressure, the breathing valve Open the exhalation gas to discharge the positive pressure; when the container bears negative pressure, the breathing valve opens the inhaled gas to discharge the negative pressure. This ensures that the pressure is within a certain range to ensure the safety of the container. One is when a certain pressure, for withdrawing the call or the other is not designed to be used purely respiratory suction may be understood as two-way valve was replaced with an appropriate pressure.

The working principle of various breathing valves:

The breathing valve plays a role in blocking the steam and water in the steam heating system. Selecting an appropriate breathing valve can make the steam heating equipment achieve high work efficiency. In order to achieve the desired effect, it is necessary to fully understand the performance and characteristics of various types of breathing valves.

There are many types of breathing valves, each with different performance. When selecting a breathing valve, first select its characteristics to meet the excellent operation of the steam heating equipment, and then consider other objective conditions, so that the choice of the breathing valve you need is correct and effective. Respiratory valves must be able to “ recognize ” steam and condensate before they can act as a barrier to steam. The " identification " of steam and condensate is based on three principles: density difference, temperature difference and phase change.

The pipeline flame arrester utilizes the difference in density between the condensate and the steam, and changes the level of the condensate so that the float lifts and opens the valve flap to open or close, thereby achieving the purpose of blocking the steam discharge. Mechanical type traps have a low degree of undercooling and are not affected by changes in working pressure and temperature. There is water and rows, and there is no water in the heating equipment, which enables the heating equipment to achieve excellent heat exchange efficiency. With a large back pressure rate of 80% and high work quality, it is an ideal breathing valve for heating equipment in the production process.

When the equipment is just started up, the air in the corrugated flame arrester pipe is discharged through the Y series automatic air discharge device. The low-temperature condensation water enters the breathing valve. The level of the condensed water rises, the float ball rises, the valve opens, and the condensed water is rapidly discharged. The equipment quickly enters the facility and the equipment heats up quickly. The temperature- sensing liquid in the Y- Series automatic air evacuation device expands, and the automatic air exhaust device closes. The breathing valve starts to work normally, and the float floats up and down with the condensate level to block the steam discharge. When the device is just started, the air and low-temperature condensate in the flame arrester pipe of the deflagration pipeline pass through the launch tube into the breathing valve. The bimetal evacuation element in the valve opens the ball barrel, the valve opens, air and low-temperature condensate Drain quickly. When steam enters the barrel, the barrel generates upward buoyancy, while the temperature inside the valve rises, the bimetal evacuation component contracts, the ball rake drifts toward the valve port, and the valve closes. When the steam in the barrel becomes condensed water, the barrel loses buoyancy and sinks, the valve opens, and the condensate drains quickly. When the steam reenters the barrel, the valve closes again, intermittently and continuously.

When the device is just started, the air and low-temperature condensate in the wall of the tank manhole enter the trap. The inverted bucket falls by its own weight. The inverted bucket connects the lever to drive the valve core to open the valve, and air and low-temperature condensate discharge rapidly. When the steam enters the inverted bucket, the steam of the inverted bucket generates upward buoyancy, and the inverted bucket rises to connect the lever to drive the valve core to close the valve. A small hole is opened in the bucket. When some steam is discharged from the hole, the other part of the steam produces condensate. The bucket loses buoyancy and sinks by its own weight. The bucket is connected to the lever to drive the valve to open the valve. Work, intermittent drainage.

The air bubble generator has two isolated valve chambers. Two stainless steel pipes connect the upper and lower valve chambers. It is a combination of a float ball type and an inverted bucket type breathing valve. The valve structure is advanced and reasonable, in overheating, high pressure and small load. Under the working conditions, the condensed water formed when the superheated steam disappears can be promptly discharged, effectively preventing the leakage of the superheated steam, and the work quality is high. The high allowable temperature is 600°C , the valve body is all stainless steel, the valve seat is a hard alloy steel, and it has a long service life. It is a special respiration valve for superheated steam. It has obtained two patents and filled the domestic gap.

When the condensate enters the lower valve chamber, the float of the secondary valve rises with the liquid level, and the float ball closes into the steam tube hole. Condensate rises into the main valve chamber through the inlet pipe, and the bucket is lowered by its own weight, which drives the valve core to open the main valve and discharges condensate. When the condensate level of the sub-valve chamber drops, the float drops with the liquid level and the secondary valve opens. The steam enters into the inverted bucket in the upper main valve cavity from the steam inlet pipe, and the inverted bucket generates an upward buoyancy force, and the inverted bucket drives the valve core to close the main valve. When the condensate level in the sub-valve chamber rises again, the next cycle starts again, intermittently draining.