JPH07317953A - Valve rod cooling structure of valve - Google Patents

Abstract

PURPOSE:To prevent the heating of a bearing by preventing the both sides of a valve rod from making at a high temperature. CONSTITUTION:A valve rod 23 penetrating a valve body 24 is formed in a hollow shaft, and in a spline shaft. At the center of the valve rod 2 in the axial direction, a central wall 31 to divide the hollow 23a and the spline groove 23b into two parts is formed. A cooling fluid leading-in passage 32 is formed by covering the spline groove 23b of the valve rod 23 with a valve body 24 and a bearing 26, and the hollow 23a of the valve rod 23 is made into a cooling fluid exhaust passage 33. At the center of the valve rod 23, a connecting hole 34 to communicate the cooling fluid leading-in passage 32 and the cooling fluid exhaust passage 33 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve stem cooling structure for a valve used for controlling a high temperature fluid.

[0002]

2. Description of the Related Art A conventional valve stem cooling structure for a valve used for controlling a high temperature fluid is shown in FIG. In FIG. 4, a valve body 4 that rotates around the axis of the valve rod 3 is arranged inside the valve housing 2 of the butterfly valve 1, and the valve body 4 is a valve body boss 4 a for inserting the valve rod 3. And a valve plate 4b for opening and closing the flow path in the valve box.
A pair of left and right valve box bosses 5 provided on both sides of the valve box 2 rotatably support the valve rod 3 via bearings 6, respectively. The valve rod 3 forms a hollow shaft and the hollow portion 7 forms a cooling fluid. A flow path of (air or water) 8 is formed, one opening of the hollow portion 7 serves as an inlet 7a for the cooling fluid 8, and the other opening opens for the cooling fluid 8.
Of the discharge port 7b.

In this structure, the cooling fluid 8 flowing into the hollow portion 7 from the inlet 7a cools the valve rod 3 and then flows out of the system from the outlet 7b. As another valve rod cooling structure, as shown in FIGS. 5 to 6, the hollow portion 1 of the valve rod 3 is used.
1 is divided by a central wall portion 12 at an intermediate position in the axial direction, and the cooling fluid introducing pipe 1 is provided in each of the hollow portions 11.
3 is inserted and a plurality of ejection holes 14 are formed on the pipe wall surface of the cooling fluid introduction pipe 13.

In this structure, the cooling fluid 8 supplied through the cooling fluid introduction pipe 13 is blown out from the ejection holes 14 and the hollow portion 11 is formed.
After flowing out inward and cooling the valve rod 3, it flows out of the system from the discharge port 11a of the hollow portion 11.

[0005]

However, in the configuration shown in FIG. 4, the difference between the temperature of the cooling fluid 8 at the inlet 7a and the temperature of the cooling fluid 8 at the outlet 7b is extremely large, and It was not possible to give a uniform cooling effect. Further, since the temperature of the valve rod 3 on the side of the discharge port 7b becomes high and the corresponding bearing 6 is heated, there is a problem that the progress of wear of the bearing 6 is accelerated and the strength thereof is weakened to shorten the life. It was

Further, in the configuration shown in FIGS.
Although there is no difference in the temperature of the cooling fluid 8 at the outlets 11a on both sides of the hollow portion 11 and a uniform cooling effect can be provided on both sides of the valve rod 3, the outlets 11 on both sides of the hollow portion 11 are provided.
Since the temperature of the cooling air 8 in "a" is high, the temperatures on both sides of the valve rod 3 are high, and there is a problem that the bearing 6 is affected by heat and its life is shortened.

The present invention solves the above-mentioned problems.
An object of the present invention is to provide a valve stem cooling structure for a valve that can prevent the temperature of both sides of the valve stem from rising and prevent the bearing from being heated.

[0008]

In order to solve the above-mentioned problems, the valve stem cooling structure for a valve according to the present invention is such that a valve body axially supported by the valve stem is rotatable in the valve box around the axis of the valve stem. In a valve in which both sides of the valve rod are rotatably supported by a valve box boss via bearings, the valve rod penetrating the valve body is formed in the hollow shaft and the spline shaft, and A hollow part and a central wall part that divides the spline groove into two parts in the axial direction are formed in the center of the axial direction, and the spline groove of the valve rod is covered with a valve body and a bearing to form a cooling fluid introduction flow path. The cooling fluid discharge passage is formed in the portion, and a communication hole that connects the cooling fluid introduction passage and the cooling fluid discharge passage is provided in the central portion of the valve rod.

[0009]

With the above structure, the introduced cooling fluid flowing into the cooling fluid introduction passage from the openings of the spline grooves at both ends of the valve rod directly cools the valve body and the bearing, and
While cooling the valve rod from the outer surface side, it flows through the cooling fluid introduction flow path toward the central portion of the valve rod. The introduced cooling fluid that reaches the deep end of the cooling fluid introduction channel flows from the communication hole into the inside of the valve rod, that is, the cooling fluid discharge channel, becomes the discharged cooling fluid, and passes through the cooling fluid discharge channel to the outside of the system. Flow out. Therefore, the hottest part of the valve rod and the bearing can be directly and efficiently cooled by the low-temperature introduced cooling fluid, and the temperature distribution in the valve rod and each part is made uniform, thereby locally reducing the strength. And thermal stress can be relaxed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 3, a valve body 24 that rotates around the axis of a valve rod 23 is arranged inside a valve box 22 of a butterfly valve 21, and the valve body 24 is for inserting the valve rod 23. A valve body boss 24a and a valve body plate 24b for opening and closing the flow path in the valve box are provided.

The valve rod 23 penetrates the valve body boss 24a, and a pair of left and right valve box bosses 25 provided on both sides of the valve box 22.
Respectively rotatably support the valve rod 23 via bearings 26. A bearing 26 is provided in the valve box boss 25 and a valve body boss 24 is provided.
A disc spring 27 is arranged to press in the axial direction of the valve rod 23 toward a, and a gland packing 28 is interposed between the bearing 26 and the valve body boss 24a. The opening of the valve box boss 25 is covered with a valve box lid 29, and the valve box lid 29 presses the shaft-sealing gland packing 30 wound around the valve rod 23 in the axial direction of the valve rod 23.

The valve rod 23 that penetrates the valve body boss 24a is a hollow shaft and is formed as a spline shaft. The hollow portion 23a and the spline groove 2 are formed in the center of the valve rod 23 in the axial direction.
A central wall portion 31 that divides 3b in the axial direction is formed. Each member of the valve body boss 24a, the bearing 26, and the shaft-sealing gland packing 30 existing around the valve rod 23 covers the spline groove 23b, so that the spline groove 23b forms the cooling fluid introduction flow path 32 and the hollow of the valve rod 23. The portion 23a forms the cooling fluid discharge flow path 33. In the central portion of the valve rod 23, a plurality of communication holes 34 that communicate the cooling fluid introduction passage 32 and the cooling fluid discharge passage 33 are provided for each spline groove 23b.

The operation of the above configuration will be described below. The introduced cooling fluid IF that has flowed into the cooling fluid introduction passage 32 from the openings of the spline grooves 23b at both ends of the valve rod 23.
Directly cools the valve body 24 and the bearing 26, and circulates through the cooling fluid introduction flow path 32 toward the central portion of the valve rod while cooling the valve rod 23 from the outer surface side.

The introduced cooling fluid IF that has reached the deep end of the cooling fluid introduction passage 32 flows into the inside of the valve rod 23, that is, the cooling fluid discharge passage 33 from the communication hole 34, and becomes the discharged cooling fluid OF and becomes the cooling fluid. It flows out of the system through the discharge flow path 33.

Therefore, the highest temperature portion of the valve rod 23 and the bearing 26 can be directly and efficiently cooled by the low temperature introduced cooling fluid IF, and the temperature distribution in the valve rod 23 and each component can be made uniform. As a result, it is possible to reduce local strength reduction and thermal stress.

[0016]

As described above, according to the present invention, since the cooling fluid introducing passage for circulating the introducing cooling fluid is formed on the outer peripheral surface of the valve rod, the outer periphery of the valve rod where the temperature is the highest. The heat transfer to the heat receiving surface of the valve can be suppressed, the valve rod can be directly cooled from the outer surface side, the bearing and the valve body can be directly cooled from the inner surface side, and the life of the bearing can be extended. In addition, by homogenizing the temperature distribution in each component, it is possible to mitigate the local decrease in strength and thermal stress.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a valve stem cooling structure of a valve according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a portion A in FIG.

3 is a cross-sectional view taken along the line CC in FIG.

FIG. 4 is a sectional view showing a valve stem cooling structure of a conventional valve.

FIG. 5 is a cross-sectional view showing a valve stem cooling structure of a conventional valve.

6 is an enlarged cross-sectional view of a B part in FIG.

[Explanation of symbols]

 22 valve box 23 valve rod 23a hollow part 23b spline groove 24 valve body 26 bearing 31 central wall part 32 cooling fluid introduction flow path 33 cooling fluid discharge flow path 34 communication hole

Claims (1)

[Claims] 1. A valve body axially supported by a valve rod is rotatably arranged in the valve box around an axis of the valve rod, and both sides of the valve rod are rotatably supported by a valve box boss via bearings. In the valve, the valve rod that penetrates the valve body is formed on the hollow shaft and the spline shaft, and the hollow portion and the central wall portion that bisects the spline groove in the axial direction are formed in the axial center of the valve rod. , The spline groove of the valve rod is covered with a valve element and a bearing to form a cooling fluid introduction flow passage, the hollow portion of the valve rod serves as a cooling fluid discharge flow passage, and the cooling fluid introduction flow passage is cooled at the center of the valve rod. A valve stem cooling structure for a valve, wherein a communication hole communicating with a fluid discharge channel is provided.