Function and characteristics of steam trap

The basic function of the steam trap is to discharge the condensed water, air and carbon dioxide gas in the steam system as soon as possible; At the same time, prevent steam leakage to a greater extent. There are many kinds of traps, each with different performance. When selecting steam trap, select its characteristics to meet the operation of steam heating equipment, and then consider other objective conditions, so that the selection of steam trap you need is correct and effective.

The steam trap needs to be able to "identify" steam and condensate, so as to play the role of steam prevention and drainage. The "identification" of steam and condensate is based on three principles: density difference, temperature difference and phase change. Therefore, three types of traps are manufactured according to three principles: mechanical, thermal static and thermal dynamic.

1. Mechanical type: depends on the change of condensate level in the drain valve.

2. Constant temperature type: works through the change of liquid temperature.

3. Thermodynamic type: works through the change of liquid thermodynamic properties.


The structure of free-floating ball trap is very simple. There is only one stainless steel hollow floating ball with finely ground moving parts inside, which is both a float and an opening and closing part. There are no wearing parts, so the service life is long. YQ drain valve is equipped with Y series automatic exhaust device, which is very sensitive, can automatically exhaust, and has high working quality.

When the equipment is started, the air in the pipeline is discharged through the Y-series automatic exhaust device, and the low-temperature condensate enters the drain valve. The condensate level rises, the float rises, the valve opens, the condensate is discharged quickly, the steam enters the equipment quickly, the equipment heats up quickly, the Y-series automatic exhaust device senses the expansion of the temperature liquid, and the automatic exhaust device closes. The steam trap starts to work normally, and the float rises and falls with the condensate water level to block steam and drain water.

The valve seat of the free float trap is always below the liquid level, forming a water seal, without steam leakage, and with good energy-saving effect. The small working pressure is 0.01Mpa, and within the range of 0.01Mpa to working pressure, it will not be affected by temperature and working pressure fluctuations, and will drain continuously. It can discharge condensate water at saturation temperature, with subcooling not less than 0, and there is no water in the heating equipment, so that the heating equipment can achieve proper heat exchange efficiency. The back pressure rate is more than 85%, which is one of the ideal traps for heating equipment in the production process.

The free semi-floating ball trap has only one semi-floating ball cylinder as the moving part, with the opening downward. The ball cylinder is the opening and closing part and the sealing part. The whole spherical surface can be sealed, with long service life, water hammer resistance, no vulnerable parts, no failure, durability, and no steam leakage. When the back pressure rate is greater than 80%, the condensate can be discharged at the saturation temperature, the degree of supercooling is not less than 0, and there is no water in the heating equipment, so that the heating equipment can achieve appropriate heat exchange efficiency.

When the device is just started, the air and low-temperature condensate in the pipeline enter the drain valve through the launch pipe, the bimetallic evacuation element in the valve pops open the ball barrel, the valve opens, and the air and low-temperature condensate are discharged rapidly. When the steam enters the ball barrel, the ball barrel will generate upward buoyancy. At the same time, the temperature in the valve will rise, the bimetallic sheet emptying element will shrink, the ball will puncture and float to the valve port, and the valve will close. When the steam in the ball drum becomes condensed water, the ball drum loses its buoyancy and sinks, the valve opens, and the condensed water is discharged rapidly. When the steam enters the ball barrel again, the valve will close again and work intermittently and continuously.

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