JPH0328237Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a disk-type steam trap that automatically eliminates condensate generated in a steam system.

A disc-type steam trap has a dual annular valve seat (inside and outside) formed on one plane of the valve casing body that forms the entrance and exit.The center opening of the inner ring seat serves as the entrance, and the annular groove between the inner and outer seats serves as the outlet. It has a structure in which a valve disk is placed on the inner and outer ring seats, and a lid is attached to the valve casing body to cover the valve disk. Therefore, the valve disk is displaceably housed in the space between the valve seat surface and the lid, that is, in the variable pressure chamber.

Function and operation will be explained. Fluid pressure from the central opening of the inner ring seat on the inlet side and fluid pressure from the annular groove on the outlet side act on the valve seat side surface of the valve disk (hereinafter referred to as the lower surface and the opposite side as the upper surface). , the fluid pressure trapped in the variable pressure chamber acts on the top surface.

When the valve is open, the static pressure between the valve disk and the valve seat changes according to Bernoulli's theorem, depending on the velocity of the fluid flowing there. Since there is a difference in flow resistance between gas and liquid, static pressure is low when vapor flows;
High when condensing water.

The disk type steam trap uses the above natural law to design the valve seat, valve disk, and variable pressure chamber so that the valve disk is seated when the discharged fluid changes from condensate to steam. When the valve is opened, a portion of the fluid flowing from the center opening of the inner ring seat toward the annular groove flows into the variable pressure chamber, so when the valve is closed, steam is trapped within the variable pressure chamber. The pressure of this steam is intermediate between the inlet and outlet sides, and the valve disk remains seated.

After the valve is closed, when condensate flows into the inlet and accumulates, the temperature of the steam trap decreases, and the pressure in the variable pressure chamber decreases as the steam inside condenses. The valve disk then separates from the valve seat when the fluid pressure acting on its upper surface becomes less than the fluid pressure acting on its lower surface. Since the flow rate of condensate is slow and the static pressure on the underside of the valve disc is high, the valve disc is separated from the valve seat while the condensate is being discharged, ie, until it is replaced by steam.

As mentioned above, the disc type steam trap is
When condensate accumulates at the inlet, the inlet side is sealed with water and the heat supply is cut off, and the heat dissipates from the valve casing to the atmosphere, causing the steam in the variable pressure chamber to condense and its pressure to drop, causing the valve to close. When the disc leaves the valve seat, the valve opens automatically.

However, when the ambient temperature is low, raindrops are falling, or the wind is blowing, heat dissipation is large, so the valve opens before sufficient condensate accumulates on the inlet side. This premature valve opening can also be caused by steam leaking in the variable pressure chamber due to imperfect sealing between the valve disk and the valve seat surface.

Conventional technology One way to solve this problem is to use the heat of the steam on the inlet side to heat the steam in the variable pressure chamber to suppress condensation, or to reevaporate the condensate in the variable pressure chamber to prevent steam leakage. It is to supplement. Jikko 46-
No. 30557 and Japanese Patent Publication No. 47-46131 propose a method of transmitting heat from the inlet side into the transformation chamber using a heat transfer tube.

This heat transfer tube is open at one end and closed at the other end. The open end opens to the inlet passage, and the closed end is located within the variable pressure chamber. Then, the fluid on the inlet side enters the heat transfer tube from the open end and heats the variable pressure chamber through the tube wall.

Problems to be Solved by the Present Invention In the above-mentioned conventional technology, when the steam on the inlet side enters the heat exchanger tube and heats the transformation chamber, the condensate generated at that time remains in the heat exchanger tube and It will block the heat pipe. Water is a poor conductor of heat, so this heat transfer tube can't actually transfer heat.

Means and action for solving the problem A variable pressure chamber is formed inside the main body and the lid, a central opening is provided at the center of the main body on the variable pressure chamber side to communicate the inlet with the variable pressure chamber, and a An annular groove is provided, an inner ring seat is formed between the central opening and the annular groove, an outer ring seat is formed around the outer periphery of the annular groove, and the annular groove and the outlet are communicated with each other, and the valve seat surface consisting of the inner ring seat and the outer ring seat is A heat valve disk in which a valve disk that is seated and taken off is placed in a variable pressure chamber, with one end facing the inlet passage between the inlet and the center opening of the inner ring seat, and the other end facing the variable pressure chamber. It is equipped with a pipe.

A heat pipe has a tube wall made of a good heat conductor, a porous pipe on the inner wall, and an evaporative heat medium sealed inside. When the endothermic end is heated, the heat medium evaporates, becomes a gas, flies to the heat radiating end at the other end, condenses there, penetrates the heat absorbing end, and returns to the endothermic end, thereby efficiently transmitting heat. be.

Therefore, when there is steam in the inlet passage, the heat of the steam is transferred to the variable pressure chamber through the heat pipe.
If condensate accumulates in the inlet passage, heat transfer will cease.

Unique effects of this invention The heat of the steam on the inlet side is transferred into the variable pressure chamber through the heat pipe, which heats the steam in the variable pressure chamber and suppresses condensation, or re-evaporates condensate in the variable pressure chamber and prevents steam leakage. Since it is possible to supplement
The disc-type steam trap according to this invention has
Premature opening of the valve will not occur even at low ambient temperatures, raindrops, wind, or even a small amount of steam leaking between the valve disc and the valve seat surface.

Embodiment An embodiment illustrating a specific example of the above technical means will be described (see FIG. 1).

A valve casing is constructed by attaching a lid 12 to the main body 10 with bolts (not shown) or the like. An inlet 22 and an outlet 24 are coaxially formed in the main body 10.

An inner and outer ring seat 28 and an outer ring seat 30 are formed on the upper end surface of the main body 10 in a double-layered manner. Both valve seat surfaces are coplanar. Center opening 26 of inner ring seat 28
communicates with the inlet 22, and an annular groove 32 between the inner ring seat 28 and the outer ring seat 30 communicates with the outlet 24.

The valve disk 14 is placed on the valve seats 28, 30. The lid 12 covers the valve seat and the valve disk, and forms a variable pressure chamber 34 between the lid 12 and the main body 10. The valve disk 14 is freely movable within the variable pressure chamber 34.

A cylindrical screen 16 is attached and arranged with a plug 18 at the bottom of the main body 10 in the drawing.
Inlet 22 is provided through central opening 26 through screen 16.
communicate with.

The heat pipe 20 bent into an L shape is connected to the inlet 2.
2 to the central opening 26 of the inner ring seat 28, with the other end facing the inside of the variable pressure chamber 34,
It is arranged to penetrate the main body 10 in an airtight manner.

To improve heat transfer efficiency, you can widen the heat transfer area by attaching fins to the heat absorption and heat radiation ends of the heat pipe, or you can bend the ends to lengthen the part facing the inlet passage or transformation chamber. good.

The operation of the disk-type steam trap described above is the same as the conventional one and is well known, so a description thereof will be omitted.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the present invention. 14...Valve disk, 20...Heat pipe,
22...Entrance, 24...Exit, 28...Inner ring seat,
30... Outer ring seat, 34... Transformation room.

Claims (1)

[Scope of utility model registration request] The main body and the lid form a transformer chamber inside, a central opening is provided at the center of the main body on the transformer chamber side to communicate the inlet and the transformer chamber, an annular groove is provided around the outer periphery of the central opening, and an annular groove is provided around the outer circumference of the central opening. An inner ring seat is formed between the grooves, an outer ring seat is formed around the outer periphery of the annular groove, and the annular groove and the outlet are communicated, and a valve disk that seats and separates from the valve seat surface consisting of the inner ring seat and the outer ring seat is installed in the transformation chamber. A disc-type steam trap equipped with a heat pipe, with one end facing the inlet passage between the inlet and the center opening of the inner ring seat, and the other end facing the transformation chamber.