JPH0322490Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a steam control valve for steam turbines, particularly for large-capacity thermal power or nuclear power plants.

2. Description of the Related Art A conventional example of a steam control valve for a steam turbine for large-capacity thermal power or nuclear power is shown in FIG. This steam control valve has a muffler 2 with a notch hole 10 for flow rate adjustment and a staggered hole 11 inserted into a valve body casing 1 from the top, and is fixed with a mounting bolt 6. Valve stem guide 9
The valve stem 4 is inserted into the valve stem guide so as to be slidable up and down. Next, a plug 3 having a side wall 12 that slides on the inner periphery of the muffler 2 is attached to the tip of the valve stem by a universal joint device 19. The plug 3 slides on the inner periphery of the muffler 2 in response to the vertical movement of the valve stem 4, thereby opening and closing the notched holes 10 and the staggered holes 11 to a desired area to adjust the amount of steam. , a seal ring 5 is provided in the groove 13 of the side wall 12 of the plug.
is fitted to maintain airtightness between the inner peripheral surfaces of the muffler 2.

Problems to be Solved by the Invention In the above-mentioned conventional steam control valve, high temperature Under high pressure conditions, vibrations and noise may occur, which has the disadvantage that the plug 3 undergoes a rotational movement that wears out the seal ring groove 13 cut into the side wall of the plug.

Means for Solving the Problem This invention was made to solve this problem, and consists of a muffler installed inside the valve body casing and a valve stem inserted into a valve stem guide inserted through the center of the upper part of the muffler. A steam control valve for a steam turbine, in which one end of a plug is attached to the tip of the valve stem, and the plug is brought into sliding contact with the inner periphery of the muffler, wherein the other end of the plug is provided with an adjustment ring groove. The steam control valve is characterized in that an adjusting ring is disposed in the adjusting ring groove and comes into contact with the guide member with a spring action to prevent vibration of the plug.

Therefore, according to the configuration of this invention, the gap between the plug and the muffler is made uniform around the circumference by the adjustment wheel, eliminating eccentricity, and moreover, the springing force of the adjustment wheel is controlled by the rotational movement of the plug. to stop.

Embodiment The first embodiment of the steam control valve of this invention is shown in the first embodiment.
Shown in Figures 2 and 3. A muffler 2 is fixed in a valve body casing 1 of the steam control valve with muffler mounting bolts 6. This muffler 2 mainly consists of an upper closing part attached to the valve body casing and a cylindrical part extending downward from this part. A notch hole 10 for flow rate adjustment and a staggered hole 11 are bored in the cylindrical portion. A valve stem guide 9 is provided through the center of the upper closed portion of the muffler 2. Therefore, the valve stem 4 slidably inserted into the valve stem guide 9 extends along the center of the cylindrical portion, and the plug 3 is attached to the tip of the valve stem via the universal coupling device 19. The plug 3 has a cylindrical side wall 12 that slides on the inner peripheral wall of the cylindrical portion of the muffler 2. Therefore, the cylindrical portion of the muffler 2 serves as a guide member for the plug 3. Two seal ring grooves 13 are cut into the upper part of the side wall of the plug 3. Seal rings 5 are fitted into these seal ring grooves 13 to maintain airtightness when the muffler cylindrical portion of the plug slides. These seal ring grooves 1
Further above 3, that is, at the top end of the side wall, an adjustment ring groove 14 is carved, and within this adjustment ring groove 14 is a chrysanthemum-shaped adjustment ring 7 formed from a thin plate with a spring action (Fig. 3). ) is inset. The outer periphery of this adjustment wheel contacts the inner periphery of the cylindrical portion of the muffler 2. A stopper ring 8 is fixed to the top surface of the side wall with a ring attachment bolt 15 to prevent the adjustment wheel 7 from coming off. This installation situation is shown in detail in FIG.

Next, a second embodiment of this invention will be explained with reference to FIGS. 4, 5 and 6. Components that are the same as those in the previous embodiment are given the same reference numerals, and detailed explanation thereof will be omitted. In this embodiment, the side wall 1 of the plug 3
An adjustment wheel holding ring 16 having an adjustment ring groove 14' cut inside is fixedly fixed to the top surface of the holding ring 2 with a holding ring mounting bolt 17. A chrysanthemum-shaped adjustment ring 7' (FIG. 6) formed by a thin plate with a spring action is inserted into the adjustment ring groove 14', and the inner circumference of the adjustment ring is connected to the cylindrical valve stem guide 9. It is in contact with the outer peripheral surface. This valve stem guide 9 serves as a guide member for the plug 3. A stopper ring 8' is fixed to the top surface of the retaining ring with a ring mounting bolt 18 to prevent the adjustment ring from coming off.

Effects of the invention According to the configuration of this invention, the gap between the plug and the muffler is made uniform around the circumference by the adjustment wheel, eliminating eccentricity which is a cause of vibration, thereby reducing the steam excitation force. In addition to preventing the occurrence of vibration, the springing force of the adjustment wheel stops the rotational movement of the plug, and as a result, wear of the seal ring groove can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view showing a first embodiment of this invention, FIG. 2 is an enlarged longitudinal sectional side view of the main part showing the engagement and arrangement of the adjustment wheel according to this invention, and FIG.
The figure is a plan view of the adjustment wheel, FIG. 4 is a longitudinal side view showing the second embodiment of this invention, and FIG.
Similarly, FIG. 6 is an enlarged vertical sectional side view of the main part showing the engagement and arrangement state of the adjusting wheel according to this invention, FIG. 6 is a plan view of the adjusting wheel, and FIG. It is a diagram. DESCRIPTION OF SYMBOLS 1...Valve body casing, 2...Muffler, 3...Plug, 4...Valve stem, 7, 7'...Adjustment ring, 9...Valve stem guide, 14, 14'...Adjustment ring groove, 19...Universal joint device.

Claims (1)

[Claims for Utility Model Registration] 1. Includes a muffler provided in a valve body casing and a valve stem inserted into a valve stem guide inserted through the center of the upper part of the muffler, with one end of a plug at the tip of the valve stem. In a steam control valve for a steam turbine, the plug is installed in a sliding contact with the inner periphery of the muffler, an adjusting ring groove is provided at the other end of the plug, and a guide member is attached to the adjusting ring groove with a spring action. A steam control valve characterized in that an adjustment ring is provided in contact with the plug to prevent vibration of the plug. 2. The steam control valve according to claim 1, wherein the guide member is a cylindrical portion of the muffler. 3. The steam control valve according to claim 1, wherein the guide member is the valve stem guide.