JP2012149664A - Float type steam trap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a float type steam trap quickly discharging a large quantity of air.SOLUTION: A valve seat 9 in which a valve hole 7 and an orifice 8 are arranged is coupled to a lid 2 of a sidewall in the lower side of a valve chamber 3. The valve hole 7 is opened directed obliquely downward. A valve chamber side opening comes closer to the valve chamber side opening of the valve hole 7 and is opened above the valve chamber side opening of the valve hole 7 in the orifice 8. A float 11 opening and closing the valve hole 7 is arranged in the valve chamber 3. A bimetal 13 having a substantial U-shape cross-section as a temperature responding member is arranged in the valve chamber 3. The bimetal 13 deforms such that the U-shape is narrowed, does not interfere with the float 11, reduces the opening area of the orifice 8, at high temperature, and deforms such that the U-shape is widened, increases the opening area of the orifice 8, lifts the float 11, and opens the valve hole 7, at low temperature. The opening area of the orifice 8 at the high temperature is formed in a size so as not to be able to discharge condensed water generated during usual operation where steam is sent to a steam piping system.

Description

The present invention relates to a steam trap that automatically discharges condensate generated in a steam piping system, and more particularly to a float steam trap that opens and closes a valve hole directly or through a valve member or the like with a closed float. It relates to the one that does not close the hole. Float steam traps automatically discharge only condensate without discharging steam using the difference in specific gravity between steam and condensate, but when non-condensed gas air flows into the valve chamber, As with steam, the valve hole is closed, causing air binding.

Therefore, conventionally, a technique as shown in Patent Document 1 has been used. This is because the casing forms an inlet, a valve chamber, and an outlet. A valve hole that connects the valve chamber and the outlet is opened obliquely downward on the lower side wall of the valve chamber, and a float that opens and closes the valve hole is placed in the valve chamber. In addition, the temperature responsive member disposed in the valve chamber prevents the float from closing the valve hole at a low temperature so as not to interfere with the float at a high temperature.

Japanese Utility Model Publication No. 48-8742

The conventional float-type steam trap is a temperature responsive member arranged in the valve chamber, which prevents the float from closing the valve hole at low temperatures, thereby discharging air from the valve hole and preventing air binding. Since only air is discharged from the valve hole, there is a problem that it takes time especially when a large amount of air has to be discharged as in the initial startup of the piping system.

Therefore, the problem to be solved by the present invention is to provide a float type steam trap capable of quickly discharging a large amount of air.

In order to solve the above problems, the steam trap of the present invention has an inlet, a valve chamber, and an outlet formed in a casing, and a valve hole that communicates the valve chamber and the outlet is opened obliquely downward on the lower side wall of the valve chamber. In the valve chamber side, a float that opens and closes the valve hole is disposed in the valve chamber, and the temperature-responsive member disposed in the valve chamber prevents the float from closing the valve hole at low temperatures and does not interfere with the float at high temperatures. An orifice is formed in which the opening is close to the valve chamber side opening of the valve hole and higher than the valve chamber side opening of the valve hole, and the opening area of the orifice is increased at a low temperature and reduced at a high temperature by the temperature-responsive member. The opening area of the orifice at a high temperature is formed so as not to be able to discharge the condensate generated during normal operation in which steam is sent to the steam piping system.

According to the present invention, the valve chamber side opening is formed close to the valve chamber side opening of the valve hole and is opened higher than the valve chamber side opening of the valve hole, and the opening area of the orifice is increased by the temperature-responsive member. The opening area of the orifice at high temperature is made large at low temperatures and small at high temperatures so that the condensate generated during normal operation when steam is fed to the steam piping system cannot be discharged. Therefore, when the temperature is low, air can be discharged from the orifice having a large valve hole and opening area, and an excellent effect that a large amount of air can be discharged quickly is achieved. In addition, since the float receives a force that draws the float in the direction of the orifice due to the flow of air or condensate discharged from the orifice, the float can easily open the valve hole. It has an excellent effect of increasing the discharge flow rate.

It is sectional drawing of the free float type steam trap concerning embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to FIG. The casing of the free float type steam trap is formed by a main body 1 and a lid 2 fastened to the main body 1 with a bolt, and has a valve chamber 3 inside. The main body 1 has an inlet 4, an outlet passage 5 and an outlet 6, and the inlet 4 communicates with the upper portion of the valve chamber 3. A valve seat 9 having a valve hole 7 and an orifice 8 is screwed to the lid 2 on the lower side wall of the valve chamber 3. The valve hole 7 opens obliquely downward. In the orifice 8, the valve chamber side opening is close to the valve chamber side opening of the valve hole 7 and opens higher than the valve chamber side opening of the valve hole 7, and the outlet side merges in the middle of the valve hole 7. The lid 2 has an outlet passage 10, and the lower portion of the valve chamber 3 communicates with the outlet 6 from the valve hole 7 and the orifice 8 through the outlet passages 10 and 5. A hollow spherical float 11 for opening and closing the valve hole 7 is disposed in the valve chamber 3 in a free state. Two float seats 12 with which the float 11 abuts at a position where the valve hole 7 is closed are provided below the float 11 and on the side facing the front side of the drawing.

A bimetal 13 as a temperature responsive member is disposed in the valve chamber 3. The bimetal 13 has a substantially U-shaped cross section and is fixed to the valve chamber 3 with a screw 14 at one end. The bimetal 13 is deformed so that the U-shape is narrowed at high temperatures and does not interfere with the float 11, and the opening area of the orifice 8 is reduced on the other end side, and is deformed so that the U-shape is widened at low temperatures. The area is increased and the float 11 is lifted to open the valve hole 7. The opening area of the orifice 8 that is reduced by the bimetal 13 at a high temperature is formed to a size that cannot discharge the condensate that is generated during normal operation in which steam is fed to the steam piping system.

The operation of the free float steam trap of the above embodiment is as follows. When a large amount of low-temperature air and condensate flows into the valve chamber 3 as in the initial startup of the steam piping system, the bimetal 13 is deformed so that the U-shape expands, and the opening area of the orifice 8 is increased. At the same time, the float 11 is lifted to open the valve hole 7, and a large amount of low-temperature air and condensate are quickly discharged from the valve hole 7 and the orifice 8 having a large opening area to the outlet 6. When the temperature of the condensate flowing into the valve chamber 3 increases due to the discharge of the low-temperature air and the condensate, the bimetal 13 is deformed so that the U-shape is narrowed so that it does not interfere with the float 11 and the orifice 8 on the other end side. The opening area is reduced, and the condensate is discharged from the orifice 8 having a reduced opening area to the outlet 6. Condensate that cannot be discharged from the orifice 8 is discharged to the outlet 6 from the valve hole 7 that is opened and closed by the float 11 that rises and falls according to the amount of condensate in the valve chamber 3. When air flows into the valve chamber 3 and the temperature in the valve chamber 3 falls below a predetermined value, the bimetal 13 is deformed so that the U-shape expands, increasing the opening area of the orifice 8 and lifting the float 11. The valve hole 7 is opened, and air is quickly discharged to the outlet 6 from the valve hole 7 and the orifice 8 having a large opening area.

In the above embodiment, the present invention is applied to the free float type steam trap, but can also be applied to a lever float type steam trap.

INDUSTRIAL APPLICABILITY The present invention can be used for a steam trap that automatically discharges condensate generated in a steam piping system such as a steam transport pipe or a steam using device.

1 Body 2 Lid 3 Valve Chamber 4 Inlet 6 Outlet 7 Valve Hole 8 Orifice 9 Valve Seat 11 Float 13 Bimetal

Claims (1)

The casing forms an inlet, a valve chamber, and an outlet. A valve hole that communicates the valve chamber and the outlet is opened obliquely downward on the lower side wall of the valve chamber, and a float that opens and closes the valve hole is disposed in the valve chamber. A temperature responsive member placed in the room that prevents the float from closing the valve hole at low temperatures so that it does not interfere with the float at high temperatures. The valve chamber side opening is close to the valve chamber side opening of the valve hole. An orifice that opens above the valve chamber side opening is formed, and the temperature-responsive member increases the orifice opening area at low temperatures and decreases it at high temperatures, and steam is supplied to the steam piping system at the orifice opening area at high temperatures. Float type steam trap, which is formed to a size that cannot discharge the condensate generated during normal operation.

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