JPH0448398Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to a thermal type drain trap that continuously squeezes and discharges a small amount of drain, and at the same time adjusts the temperature to the desired drain discharge temperature using a control lever attached to the valve. By making it possible to set accurately the
It is designed to be used in a wide range of fields.

[Prior art and its problems] The basic types of conventionally known drain traps include float type, bucket type, disk type, and others.
There are thermostatic types, bimetal types, etc.
In all of the former three, the valves are opened and closed depending on the amount of accumulated condensate, or the valves are opened and closed intermittently regardless of the amount of accumulated condensate, so the fluid temperature cannot be directly controlled. However, although the latter two are thermal mechanisms that open and close the valve by sensing the fluid temperature, both have limitations in their compatibility with steam temperature and pressure conditions due to the structure of the valve. There were still many problems in terms of drain temperature setting.

[Means for solving problems]

In view of these circumstances, the present invention combines a metal material with a relatively high coefficient of thermal expansion and a ceramic material with an extremely low coefficient of thermal expansion as a mechanism that senses the fluid temperature and opens and closes the valve. The valve automatically opens and closes due to the difference in thermal expansion that occurs between the two members in response to the fluid temperature, and at the same time, the temperature of the fluid to be discharged can be adjusted as desired by an operating lever attached to the other side of the valve case. This method solves all the problems in the conventional drain traps described above.

That is, the drain trap of the present invention includes a relatively long cylindrical metal valve box provided with a drain inlet and an outlet, and a valve seat that is engaged and supported by the inner stage of the valve box provided near the inlet. , and a valve body that is pressed against the valve seat via a spring on the upstream side. While the strut can be operated by contacting the tip, the strut can be slid a certain amount inside the valve case by means of a control lever at the end of the valve stem, which penetrates from the outside of the valve case. be.

[Effect]

The drain trap of the present invention having the above-mentioned configuration is such that the constituent members of the internal fluid temperature sensing section are arranged concentrically in the valve axis direction, and are made of ceramic and metal materials with a large difference in thermal expansion. It has a simple structure, provides a strong operating force when opening the valve, and has an exceptional effect in that the temperature of the discharged fluid can be adjusted.

〔Example〕

Hereinafter, the configuration of the present invention will be described in more detail according to the embodiment shown in the drawings. 1 has an inlet port 1a and an outlet port 1b, and has a relatively long length made of a metal material with a high coefficient of thermal expansion, such as SUS304. Cylindrical valve box, 2
3 is a hollow valve seat supported and fixed to the inner step 1c provided on the inlet 1a side of the valve case 1, and 3 is a coil spring 4 on the back side located upstream of the valve seat 2.
a valve body that is normally pressed against the valve seat surface through the
Reference numeral 5 denotes a strut made of ceramics that is loosely fitted over almost the entire length of the inner space 1b of the valve case 1 so as to be able to slide by a certain amount, and the tip of the strut passes through the hole in the valve seat 2 and is inserted into the valve body. 3 so that the valve body 3 can be pushed.

Furthermore, reference numeral 6 denotes a valve stem that penetrates watertightly in the axial direction from the other end of the valve case 1, and its inner end abuts the strut 5, and the rotation of the operating lever 7 provided at its outer end causes the The strut 5 is configured to be able to slide a certain amount in the axial direction.

In the figure, 8 is a cover containing the valve case 1, 9 is a fixing pin for the operating lever 7, 10 is a scale plate that displays the movement amount of the valve stem 6 or the drain discharge temperature, and 11 is a scale plate that displays the movement amount of the valve stem 6 or the drain discharge temperature. Valve seat holder, 12 indicates a filter.

In addition, although no particular mention was made of the materials of the valve seat 2 and the valve body 3 in the above embodiments, as the fluid in the steam pipe increases in temperature and pressure, valve seats with small intervals,
Since it is anticipated that a fluid with a high differential pressure will pass between the valve bodies, it is preferable that both the valve bodies be made of ceramic material.

Therefore, in actual use of the proposed drain trap, a drain pipe (D.
After mounting on P), the operation lever 7 is rotated in advance to set the desired fluid temperature on the scale plate 10, and this operation causes the valve stem 6 to move the valve body 3 by a certain amount via the strut 5. It is pushed and moved to separate the valve seat from the two surfaces to maintain an appropriate distance [S]. Now, the trap of this invention used in this normal state is that if the temperature of saturated water or condensed water accumulated in the drain pipe (DP) is within the set value, the drain flowing from the drain pipe will first be set. It passes through the valve opening gap [S], flows down along the inner surface of the valve case and the inner space 1d of the strut 5, and is continuously discharged through the outlet 1b.

On the other hand, when the temperature of the water in the drain passing through the trap rises to a predetermined temperature or higher as the drain is discharged, the valve case 1 having a large coefficient of thermal expansion expands due to the difference in expansion with the strut 5 in the axial direction. As a result of the retraction of the strut 5, the valve body 3 is brought into close contact with the valve seat 2 under the influence of the coil spring 4 on its back surface and the fluid pressure on the primary side, thereby reliably blocking drain discharge.

However, if the fluid temperature on the drain pipe side drops below the set value, the valve box 1 of the drain trap that radiates heat will contract, and the valve body 3 and valve The positional relationship of locus 2 is restored,
Discharge of the drain is restarted.

[Effect of idea]

As mentioned above, the drain trap of this invention continuously discharges a small amount of condensate under normal conditions, and when the fluid temperature rises, it automatically shuts off the discharge of condensate to maintain the fluid temperature inside the drain pipe at a predetermined value. However, in addition to using a reverse plug type temperature sensing mechanism that uses ceramics and metal materials that have a significant difference in thermal expansion from each other over a long range in the axial direction, the valve body and valve seat are made of ceramics. By configuring this, it is possible to continuously squeeze and discharge high-temperature, high-differential-pressure drain. The gap [S] between the valve body and valve seat can be easily adjusted at any time using the operating lever 7. In addition, we have made it possible to fully open the valve.
Coupled with the fact that fully closed can be selected, it can be used in a wide range of applications for various piping systems with severe drain discharge temperature settings and usage conditions.

Therefore, as shown in Figure 4, drain valves (DV) for main steam pipes in recent thermal power plants, etc.
As shown in the figure, it is extremely advantageous as a bypass valve for the purpose of greatly mitigating the thermal shock generated in the entire drain system such as piping and valves due to the passage of main steam when the drain is suddenly discharged due to opening of the valve. , many excellent practical advantages can be expected.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view of the central part of the drain trap of the present invention, Figure 2 is a partial cross-sectional view showing an enlarged view of its main parts, Figure 3 is a front view of the scale plate, and Figure 4 is a view of other drain traps of the present invention. This is an installation example. In the figure, 1...valve box, 2...valve seat, 3...valve body, 5...strut, 6...valve stem, 7...operating lever, 10...scale plate.

Claims (1)

[Claims for Utility Model Registration] 1. A relatively long cylindrical metal valve case 1 having an inlet port 1a and an outlet port 1b, and a valve case 1 that is engaged and supported by an inner step 1c of the valve case provided near the inlet port. Valve seat 2
and a valve body 3 which is pressed against the valve seat via a spring 4 on the upstream side thereof. While it can be operated by coming into contact with the tip of the ceramic strut 5 provided in the
The strut is a valve stem 6 that penetrates from the outside of the valve case 1.
A drain trap characterized in that it can be slid within a valve case 1 by a certain amount by an operating lever 7 at the end of the valve stem. 2. The drain trap according to claim 1, in which the valve body 3 and the valve seat 2 are made of ceramics.