JP2884302B2 - Pilot type steam 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 steam trap for automatically discharging condensate generated in a steam piping system, and more particularly, to a pressure responsive valve which detects a liquid level at an inlet side by a pilot float valve. The present invention relates to a pilot-operated steam trap.

[0002]

2. Description of the Related Art A conventional pilot type steam trap will be described with reference to Japanese Utility Model Laid-Open No. 3-85797. This includes a pressure chamber partially formed by the pressure-receiving displacement wall of the pressure-responsive valve, a pilot flow path communicating the pressure chamber to the inlet side, a relief flow path communicating the pressure chamber to the outlet side, and a pilot flow path. And a pilot float valve that opens and closes according to the liquid level on the inlet side and controls the pressure in the pressure chamber to operate the pressure responsive valve.

[0003]

In the above arrangement, when the pressure responsive valve is opened by opening the pilot flow path by the pilot float valve, rapid discharge of the condensed water to the outlet side is started. There was a problem that water hammer occurred on the exit side.

Accordingly, it is an object of the present invention to prevent a water hammer on the outlet side due to the opening of the pressure responsive valve.

[0005]

Means for Solving the Problems The technical means of the present invention taken to solve the above-mentioned technical problem is to provide a pressure chamber partially formed by a pressure-receiving displacement wall of a pressure responsive valve, and a pressure chamber. Operates the pressure responsive valve by controlling the pressure in the pressure chamber by opening and closing the pilot flow path communicating with the inlet side, the relief flow path communicating the pressure chamber with the outlet side, and the pilot flow path according to the liquid level on the inlet side. And a pilot flow valve, which is opened at a lower liquid level than the pilot flow valve opened by the pilot float valve and communicates the inlet side to the outlet side. It is a feature.

[0006]

The operation of the above technical means is as follows.
Since the bypass flow path is opened prior to the opening of the pilot flow path, when the pressure-responsive valve opens thereafter, the condensate on the inlet side is discharged to the outlet through the bypass flow path.
Therefore, even if the condensed water is rapidly discharged to the outlet side by opening the pressure responsive valve, no water hammer is generated.

[0007]

1 to 3 show specific examples of the above technical means.
This will be described with reference to FIG. Lids 2 and 3 are fixed to the main body 1 to form a trap case. The inside of the trap casing is separated by a partition wall 4 into a condensate sump chamber 6 communicating with an entrance 5.
And a pilot float valve housing chamber 9 communicating with the condensate sump chamber 6 via the vertical communication passages 7 and 8 and a pressure responsive valve housing chamber 11 communicating with the outlet 10. Inlet 5 is condensate sump room 6
The outlet 10 is formed on the same axis as the inlet 5.

The pilot float valve chamber 9 communicates with a pressure chamber 25 described below via a pilot flow path 12 (indicated by a two-dot chain line in FIG. 1) and communicates with an outlet 10 via a bypass flow path 13. . A pilot float valve 14 having a hollow seal is accommodated in the pilot float valve accommodation chamber 9 in a free state. The pilot float valve 14 rises and falls in accordance with the liquid level in the pilot float valve storage chamber 9, and opens and closes the bypass passage 13 directly on the outer surface thereof, and is rotatable by the pin 15. The pilot flow path 12 is opened and closed via a lever 16 attached to the valve chamber 9.
The drawing shows a state in which both the bypass channel 13 and the pilot channel 12 are closed. In this state, when the pilot float valve 14 rises due to the rise of the liquid level, the bypass flow path 13 is first opened, and the lever 16 is further lifted at the position where it floats.
Is rotated clockwise in FIG. 2 to open the pilot channel 12. When the pilot float valve 14 descends to the position shown in the figure due to a decrease in the liquid level, the bypass flow path 13 closes on the outer surface and the pilot flow path 12 closes via the lever 16.

A cylinder 17 is provided in the pressure-responsive valve accommodating chamber 11,
The valve seat 18 is arranged. Condenser chamber 6 and outlet 10 are valve seats 1
The communication is made by a valve port 19 and a fluid passage window 20 opened in 8. Piston 2 sliding airtightly in cylinder 17
1 and a valve body 22 for opening and closing the valve port 19 from the condensate sump chamber 6 side
And form a pressure responsive valve. In the valve body 22, the valve rod portion 23 penetrates the top wall of the valve seat 18, further penetrates the piston 21,
The piston 21 is fixed by the nut 24. The space above the piston 21 forms a pressure chamber 25 and the pilot flow path 1
2 communicates with the condensate sump chamber 6 side. Pressure chamber 25
Is connected to the outlet 10 side through a communication passage 27 opened in the valve seat 17 by a relief passage 26 having a smaller passage area than the pilot passage 12 penetrating the piston 21.

The operation of the above embodiment is as follows. When the liquid level in the pilot float valve storage chamber 9 rises due to the condensate flowing from the inlet 5, the pilot float valve 14
Rises from the position shown in the figure, opens the bypass passage 13 and directly discharges the condensate to the outlet 10. If the inflow condensate is large, the float further rises and the pilot flow path 12 is opened via the lever 16. Since the pressure in the pressure chamber 25 rises due to the condensed water introduced from the pilot flow path 12, the piston 21 is displaced downward, and accordingly, the valve body 22 separates from the valve seat 18 to open the valve port 19. The condensate is discharged to the outlet 10. When the liquid level in the pilot float valve accommodating chamber 9 drops due to the discharge of the condensate water, the pilot float valve 14 drops to the position shown in the drawing, closes the bypass passage 13 on the outer surface, and passes through the lever 16. To close the pilot flow path 12. Since the pressure in the pressure chamber 25 is reduced by the relief channel 26, the valve body 22 closes the valve port 19.

[0011]

The present invention has the following specific effects. As described above, according to the present invention, since no water hammer is generated, the steam-using equipment is not damaged or becomes unusable. Since the condensate is directly discharged to the outlet through the bypass flow passage, the frequency of operation of the pressure responsive valve is reduced,
The service life of the pressure responsive valve can be extended.

[Brief description of the drawings]

FIG. 1 is a sectional view of a pilot type steam trap according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1 with a part omitted.

FIG. 3 is a plan view of FIG. 1 with a part omitted.

[Explanation of symbols]

 5 Inlet 6 Condensate Reservoir 9 Pilot Float Valve Housing 10 Outlet 11 Pressure Responsive Valve Housing 12 Pilot Flow Path 13 Bypass Flow Path 14 Pilot Float Valve 16 Lever 19 Valve Port 21 Piston (Pressure Responsive Valve) 22 valve body (pressure-responsive valve) 25 pressure chamber 26 relief channel

Claims (1)

(57) [Claims] A pressure chamber partially formed by a pressure-receiving displacement wall of a pressure-responsive valve; a pilot flow path communicating the pressure chamber to the inlet side; a relief flow path communicating the pressure chamber to the outlet side; A pilot flow valve that opens and closes the flow path according to the liquid level on the inlet side and controls the pressure in the pressure chamber to operate the pressure responsive valve. A pilot type steam trap, wherein a bypass flow path is opened at a lower liquid level than the valve and communicates an inlet side to an outlet side.