JPS6118080B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disk-type steam trap for discharging condensate generated in steam-using equipment and the like.

This tends to occur when the valve disc is used for high temperature and high pressure applications, but leaks occur even when the valve disc is in the seated position, resulting in circular radial erosion marks on the inner ring seating surface and the area where the valve disc contacts the inner ring seat. There was a problem.

This is believed to be due to a thin layer of water interposed between the valve seat and the valve disk. 4, which shows a state in which the valve disk 1 is seated on the inner ring seat 3 and the outer ring seat 4 of the valve seat member 2, will be described. The abutting valve surface on the lower surface of the valve disk 1 is polished to a perfectly flat surface, and the abutting valve seat surfaces of the inner and outer ring seats 3 and 4 are also polished to be completely flush. In this way, when the valve disk 1 is seated on the valve seats 3 and 4, a thin layer of water is formed between the contact surfaces, and although it is exaggerated in FIG. 4, the valve disk 1 is seated on the valve seats 3 and 4. , 4 is considered to be about 0.001 to 0.01 mm higher. Therefore, when considering the pressure in the variable pressure chamber 5 surrounding the valve disk 1, the annular groove 7 communicating with the discharge hole 6, and the ejection hole 8, the difference between the pressure in the ejection hole 8 sandwiching the inner ring seat 3 and the pressure in the annular groove 7 is determined. The pressure is much larger than the differential pressure between the pressure in the variable pressure chamber 5 that sandwiches the outer ring seat 4 and the pressure in the annular groove 7, and for this reason, the water layer 9 between the valve disk 1 and the outer ring seat 4 remains and the valve Although the disk 1 is kept floating, the layer of water between the valve disk 1 and the inner ring seat 3 is pushed out, and it is thought that leakage occurs even though the valve disk 1 is in the seated state.

The present invention aims to solve the above-mentioned problem, and is capable of self-controlling the valve disk, which sits on and off from the valve seat surface consisting of an inner ring seat and an outer ring seat, by changing the pressure in a variable pressure chamber formed behind the valve disk. A plurality of heating holes are provided around the entire circumference of the outer ring seat, extending upward from the inlet passageway and communicating with the lower side of the outer ring seat surface.

The action is as follows.

A disc type steam trap opens and closes a valve disc based on pressure changes in the variable pressure chamber. When the valve is closed, there is no condensate in the inlet passage.
Alternatively, a small amount of condensate is present, and when the valve is opened, the condensate present in the inlet passage is discharged. Since a heating hole is provided that communicates from the inlet passage to the lower side of the outer ring seat, the outer ring seat is heated by the steam in the heating hole when the valve is closed.
Even if the heat of the steam is consumed by heating and becomes condensate, since the heating hole is formed upward from the inlet passage, the condensate will fall downward and replace the steam in the inlet passage, and the condensate will flow into the heating hole. Passage steam is supplied. Therefore, when the valve is closed, the outer ring seat is heated by the steam in the heating hole, so the thin layer of water remaining between the valve disk and the outer ring seat is heated and dried, and the valve disk is heated inside and out. You can sit on the ring valve seat,
No leakage occurs.

The illustrated embodiment will be described in detail below.

In FIG. 1, 10 is a main body, 11 and 12 are an inlet passage and an outlet passage formed in the main body 1, respectively.
13 is a bolt and nut 1 through a gasket 14.
The lid body 5 is attached to the main body 10, and the inner lid 17 is attached to the main body 1 with bolts 18, and 16 is a valve seat member. 19 is a gasket interposed between the valve seat member 16 and the inner lid 17; 20 is the valve seat member 16 and the main body 10;
There is a gasket in between. 21 is an outer chamber communicating with the inlet passage 11, and 22 is a cylindrical filter. Reference numerals 23 and 24 denote an inner ring seat and an outer ring seat, respectively, and the seating surfaces are polished to be completely flush with each other.
A valve disk 25 is seated on the inner and outer ring seats 23 and 24, the lower seating surface of which is polished to a completely flat surface, and is placed freely within the variable pressure chamber 26. 2
Reference numeral 7 designates an injection hole that communicates with the inlet passage 11 and opens into the inner ring seat 23, and 28 represents a discharge hole that communicates with the outlet passage 12 from an annular groove 29 between the inner and outer ring seats 23 and 24.
30 is a bimetal ring, and 31 is a retaining ring.

FIG. 2 shows the appearance of the valve seat member 16, and FIG. 3 shows a cross section taken along the line AA.

As can be seen from Figures 1 and 3, the outer ring seat 24
A plurality of heating holes 32 are provided that reach close to. The heating hole 32 communicates with the inlet passage 11 .

With the above configuration, when the valve is closed, that is, when there is no condensate in the inlet passage 11, or when the valve disc 25 is seated with a small amount of condensate, the outer ring seat 24 is heated by steam through the heating hole 32, and the valve The thin layer of water that forms between the disc 25 is dried. Therefore, the valve disk 25 is completely directly seated on the inner and outer ring seats 23, 24, and leakage and accompanying erosion of the inner ring seat 23 and the valve disk 25 are prevented.

As described above, according to the present invention, by the heating space located near the outer ring seat and communicating with the inlet passage,
In particular, it is possible to prevent leakage when the valve is closed and corrosion of the valve seat and valve disk, which tend to occur with high-pressure traps.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a disk-type steam trap according to an embodiment of the present invention, FIG. 2 is a partial external view of a valve seat member, FIG. 3 is an enlarged sectional view taken along line A-A in FIG. The figure is an explanatory view partially exaggerating a conventional state in which the valve disk is seated on the valve seat. 11 is an inlet passage, 16 is a valve seat member, 23 is an inner ring seat, 24 is an outer ring seat, 25 is a valve disk, 26 is a variable pressure chamber, 27 is an injection hole, 28 is a discharge hole, 29 is an annular groove, and 32 is a heating space. It is a heating hole that forms a

Claims (1)

[Claims] 1 In a valve disk that is seated and separated from a valve seat surface consisting of an inner ring seat and an outer ring seat, the valve is opened and closed by self-control by pressure changes in a variable pressure chamber formed behind the disk, and the inlet passage A disc-type steam trap with multiple heating holes all around the outer ring seat that extend upward from the outer ring seat to the bottom of the outer ring seat.