JPH01131397A - Large capacity steam trap at time of low pressure - Google Patents

Abstract

PURPOSE: To only exhaust condensate while preventing the steam leakage even under a low pressure by arranging within condensate accumulating chambers a float valve that can open a valve opening over the whole range of the use pressure and a float valve that can only open a valve opening when the use pressure is within a predetermined low range. CONSTITUTION: An upper condensate accumulating chamber 5 and a lower condensate accumulating chamber 6 are formed in a main body having an inlet 7 and an outlet 8. A free float 18 for opening and closing a valve opening 10 is arranged in the upper condensate accumulating chamber 5 and a downward release bucket float 19 for opening and closing a valve opening 11 is arranged in lower condensate accumulating chamber 6. The valve opening 10 is set to a smaller area so as to be opened by a float valve 18 over the whole use pressure range. The valve opening 11 is set to a large area so as to be only opened by the float valve 19 within a low use pressure range. As a consequence, only the condensate is exhausted rapidly without causing the occurrence of steam leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a float-type steam trap that opens and closes a valve opening by raising and lowering a float, and particularly relates to a float-type steam trap that discharges only a large amount of condensate at low pressure. Regarding hanging steam traps.

A steam trap is an automatic valve that is attached to steam-using equipment or steam piping and discharges only condensate. However, when steam is first used, many meters of condensate is generated because the equipment and piping are cold. It is a common usage method that the amount of condensate generated decreases significantly when the usage state enters a steady state.

BACKGROUND OF THE INVENTION Conventionally, a low-pressure, large-capacity steam trap as proposed in Japanese Patent Application No. 61-279293 has been used. This includes a first valve seat having a large valve hole area that is fixedly provided on the condensate reservoir side, and an annular gap formed on the outside that is accommodated in the valve hole of the first valve seat so that it can move forward and backward. a second valve seat member having an enlarged portion that closes in contact with the first valve seat and a second valve seat on which the float valve is seated at the end on the condensate reservoir chamber side; and the second valve seat member is returned from the first valve seat side. When the differential pressure is below a predetermined value, such as when steam starts to be used, the first valve hole, which has a large valve hole area,
The valve seat is opened by spring force to discharge condensate.

Problems to be Solved by the Present Invention In the above case, assume that steam has flowed in until the differential pressure reaches a predetermined value, that is, the pressure differential is such that it can overcome the spring force and seat the first valve seat. The problem is that the valve continues to remain open, causing steam leakage, and as the position of the second valve seat moves, the float valve oscillates, making its seating unstable and causing steam leakage. That's the problem.

The technical problem of the present invention is to prevent steam from leaking even at low pressure, to discharge only a large amount of condensate, and to securely seat the float valve to prevent steam leakage.

Means for Solving the Problems The technical means of the present invention taken to solve the above-mentioned technical problems is that a plurality of valve ports opening into a condensate storage chamber connected to an inlet are connected to an outlet of the same valve. Connected to the outlet passage, a plurality of float valves are housed in the condensate storage chamber so as to float up and down in the chamber to open and close each valve port, and at least one valve port has a corresponding float valve that operates over the entire working pressure range. The valve opening is sized so that the valve can be opened over a range of 1 to 300 m, while the other valve openings are sized so that they can be opened only within a predetermined low working pressure range.

action The operation of the above technical means is as follows.

This steam trap has a relatively small valve opening that opens over the entire operating pressure range and discharges only condensate.
There is a valve with a relatively large valve area that opens only in a predetermined low pressure range and discharges only condensate, and when the inlet side, that is, the condensate storage chamber side, is at a low pressure below the predetermined pressure, such as during startup. In this case, all valve ports open and only condensate is immediately discharged.

When the pressure rises above a predetermined value, condensate is discharged only through the valve port with a small valve port area.

Effect of the invention The present invention produces the following unique effects.

Even at low working pressures, only condensate is discharged and no steam leaks occur. In addition, since the valve seat position does not move, the float valve is stable and is securely seated at the valve port, thereby preventing steam leakage.

Embodiment An embodiment illustrating a specific example of the above technical means will be described. (
(See Figure 1) In this embodiment, a free float and a packet float are used as the float valve.

The upper body 3 is placed between the lower body 1 and the lid 2, and the gasket 16 is placed between the lower body 1 and the lid 2.
．． 17 with bolts 4 to form a valve casing, and condensate reservoir chambers 5 and 6 are provided inside to communicate with the hero. The upper condensate reservoir chamber 5 accommodates a free float 18 disposed in a free state, and the lower condensate reservoir chamber 6 accommodates a downwardly open packet float 19 also disposed in a free state. The upper body 3 partitions the upper and lower condensate storage chambers 5 and 6, and
It passes through the communication hole 22 and communicates the lower condensate reservoir chamber 6 with the inlet lower. An outlet 8 is provided on the same axis as the input lower. Upper body 3
and a valve port 10 communicating with the outlet 8 via the same outlet passage 9.
, 11 are installed by screwing on the valve seats 12 and 13. The valve seats 12, 13 are each mounted in a gas-tight manner on the upper body 3 by means of gaskets 14,15. The valve port 10 is sized to allow the corresponding free float 18 to open over the entire operating pressure range, and the valve port 11 is sized to allow the downwardly opening packet float 19 to open only in a predetermined low pressure range. A float support seat 20 is provided on the upper body 3 facing the valve seats 12 and 13.
．． Form 21. The float support seats 20 and 21 are double-seat seats so that the float does not move when the valve is closed, and are finished with high precision so that they are securely seated. The through hole 22 is
Pass through the inlet passage 24 to the lower condensate reservoir chamber 6, and enter the condensate reservoir chamber 6.
It communicates with the condensate reservoir chamber 6 through an introduction pipe 23 attached to the bottom wall of the chamber. A screen 25 for capturing dust and scale is provided in a part of the entrance passage 271.

The mixed fluid of condensate and steam flowing from the hero flows down into the upper and lower condensate storage chambers 5.6. When the pressure on the inlet lower side is lower than a predetermined value, the free float floats up as condensate flows down, and the downward-opening free packet descends, leaves the valve seats 12 and 13, and moves to the valve port 10. 11 is opened and only the condensate is discharged to the outlet 8 side. When the pressure on the inlet lower side is higher than a predetermined value, the downwardly open free packet 19 in the lower condensate reservoir 6 is closed by the valve seat 1 due to the differential pressure.
3, the valve remains closed, and the condensate flowing down from the hero is discharged from the outlet 8 via the valve port 10 at the top.

As mentioned above, even when the working pressure is low, only condensate is discharged, and each float is connected to the valve seats 12 and 13.
to ensure that it is seated securely without causing steam leakage. In addition, the valve seats 12, 13 can be attached to the upper body 3, and the float support seats 20, 21 can all be provided, which facilitates machining and improves machining accuracy.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a low-pressure, large-capacity steam trap showing an embodiment of the present invention. 1: Lower body 3: Upper body 5: Upper condensate reservoir chamber 6: Lower condensate reservoir chamber 7: Eight mouths
8: Outlet 9: Outlet passage 10, 11: Valve port 12.13: Valve seat ]] 8: Free 70-to 19: Bottom open free packet

Claims (1)

[Claims] 1. Connect multiple valve ports that open to the condensate reservoir chamber connected to the inlet to the same outlet passage communicating with the outlet, and float and lower multiple float valves in the condensate reservoir chamber to separate each valve. At least one valve port is sized to allow the corresponding float valve to open over the entire working pressure range, and the other valve ports open only within a predetermined low working pressure range. Large capacity steam trap at low pressure.