JP2745270B2 - Positive and negative pressure trap - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piping system in which relatively low-pressure steam at a pressure higher than the atmospheric pressure and steam depressurized at a pressure lower than the atmospheric pressure are used as a heating source, and condensate generated therefrom is discharged. The present invention relates to a trap for both positive pressure and negative pressure. The main reason for using steam as a heating source is that it has features such as a larger heat transfer amount than hot water, a large heat transfer coefficient, and uniform temperature heating.

[0002]

2. Description of the Related Art A heating apparatus of this type uses a relatively low-pressure steam at a pressure higher than the atmospheric pressure or a steam depressurized at a pressure lower than the atmospheric pressure, and is configured as shown in FIG. The steam sent from the steam source 21 is decompressed by the pressure control valve 22 in accordance with the required temperature of the heat use part 23. For example, if the required temperature is 120 ° C., it becomes 3.0 kg / cm ² (gage pressure). , 80 degrees, the pressure is reduced to 380 Torr. In order to discharge the condensate generated in the heat use part 23, a vacuum pump 26 is connected downstream via a pipe line in which a trap 24 and a bypass valve 25 are connected in parallel.

The bypass valve 25 is necessary for maintaining the steam pressure of the heat using section 23, that is, the primary pressure of the trap 24, at a predetermined pressure equal to or lower than the atmospheric pressure. .

[0004]

SUMMARY OF THE INVENTION In the above prior art,
Since the bypass valve 25 is required, and the bypass valve 25 is opened at a constant opening, there is a problem that the steam loss is large. Of course, when the low-pressure steam having a pressure higher than the atmospheric pressure is used in the heat use unit 23, the steam loss can be reduced by closing the bypass valve 25. However, the operation of the bypass valve 25 is required, which is troublesome. Accordingly, it is an object of the present invention to provide a positive pressure / negative pressure trap which can omit a bypass circuit including a bypass valve and can reduce steam loss.

[0005]

Means for Solving the Problems The technical means of the present invention taken to solve the above technical problem is that a condensate pool is provided between a condensate sump chamber connected to an inlet and an outlet connected to a vacuum source. Deviation between the pressure in the condensate sump chamber and the outside air pressure in a trap having a float valve that is displaced between a closed position that closes the valve hole opened in the condensate sump chamber and an open position that opens the valve hole in response to the water level in the chamber And a pressure responsive member for displacing the float valve to the open position.

[0006]

The operation of the above technical means is as follows.
The pressure responsive member is displaced based on the deviation between the pressure in the condensate sump chamber and the outside air pressure, and drives the float valve to the open position when the pressure in the condensate sump chamber is a negative pressure equal to or lower than the atmospheric pressure. Is forcibly opened. Further, when the pressure in the condensate storage chamber is a positive pressure higher than the atmospheric pressure, the float valve is not involved in the float valve. In this case, the valve hole is opened and closed by the rising and falling corresponding to the water level of the float valve. Therefore, it is possible to obtain a trap for both positive pressure and negative pressure in which the bypass circuit including the bypass valve is omitted, and when the pressure of the condensate storage chamber is a positive pressure higher than the atmospheric pressure, the condensate storage chamber always communicates with the outlet. Since it is not what it does, steam loss can be reduced.

[0007]

An embodiment showing a specific example of the above technical means will be described (see FIG. 1). Lid members 2 and 3 are fastened to the main body 1 to form a valve casing having a condensate reservoir chamber 4 therein. Condensate sump chamber 4 having a primary connection at the top of body 1
Is formed, and an outlet 6 having a secondary connection on the same axis as the inlet 5 is formed. A valve seat member 8 having a valve hole 7 is disposed on the lower side of the main body 1, and the condensate reservoir chamber 4 and the outlet 6 are communicated through the valve hole 7. Float valve 9 which rises and falls in condensate sump chamber 4 according to the liquid level to open and close valve hole 7
Is placed in a free state.

A piston 10 as a pressure responsive member is disposed at the bottom of the main body 1. The upper surface of the piston 10 is acted upon by the pressure of the condensate reservoir chamber 4, and the lower surface is acted upon by an outside air pressure through an outside air connection opening 11 opened in the lid member 3. The piston 10 has an operating member 13 fixed with a nut 12,
The tip of the operating member 13 is displaced between a position where the float valve 9 is lifted and driven to the open position and a position where the float valve 9 is not involved in the float valve 9.

When the pressure in the condensate storage chamber 4 is a negative pressure equal to or lower than the atmospheric pressure, the piston 10 is displaced upward and the operating member 1
Lift the float valve 9 at the end of 3 and drive it to the open position. As a result, the valve hole 7 is forcibly opened. When the pressure in the condensate storage chamber 4 is a positive pressure higher than the atmospheric pressure, the piston 10 is displaced downward, and the tip of the operating member 13 does not participate in the float valve 9. In this case, the valve hole 7 is opened and closed by the floating descending in response to the water level of the float valve 9.

[0010]

The present invention has the following specific effects. As described above, the positive pressure and negative pressure combined trap according to the present invention is:
Since the bypass circuit including the bypass valve can be omitted, the structure can be simplified and the cost can be reduced. In addition, when the pressure in the condensate storage chamber is a positive pressure higher than the atmospheric pressure, the condensate storage chamber and the outlet are not always in communication, so that the steam loss can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a positive pressure / negative pressure trap according to an embodiment of the present invention.

FIG. 2 is a configuration diagram schematically showing a conventional heating device using reduced-pressure steam.

[Explanation of symbols]

 4 Condensate Reservoir Room 5 Inlet 6 Outlet 7 Valve Hole 9 Float Valve 10 Piston 11 Open Air Connection Opening 13 Operating Member

Claims (1)

(57) [Claims] 1. A closed position for closing a valve hole opened in a condensate sump chamber in response to a water level of a condensate sump chamber between a condensate sump chamber connected to an inlet and an outlet connected to a vacuum source. In a trap having a float valve which is displaced to an open position, a pressure responsive member which is displaced based on a deviation between the pressure of the condensate reservoir chamber and the outside air pressure and drives the float valve to the open position is provided. Positive and negative pressure combined trap.