JPH0314621Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a butterfly valve used for controlling fluids that have high viscosity at room temperature, such as tar, pitch, and resin, and fluids that crystallize and solidify.
The outer peripheral surface of the valve body of the butterfly valve is covered with a jacket cover, and a heat medium such as steam, hot water, or dowsum is passed through the jacket cover to heat the valve body from the outside, thereby reducing the fluid inside the valve. This invention relates to a so-called jacket-type butterfly valve that lowers the viscosity of water and makes it easier to flow.

(Prior art) This type of conventional jacket type butterfly valve is
As shown in FIGS. 2a and 2b, due to the structure of the valve, the neck portion of the valve body 1, that is, the vicinity of the support portion 3a of the upper valve stem 3 1
a and the bottom portion, that is, the vicinity of the lower valve stem support portion 3b 1b
However, since this is extremely inconvenient when installing the jacket cover 4, the jacket cover 4 is separated into left and right halves in FIG. It had a structure in which it was divided into 4b parts and welded separately 4c. Therefore, the heat medium inlet and outlet are provided in pairs 5a, 6a and 5b, respectively, in the separate jacket covers 4a and 4b divided as described above.
6b, it had no choice but to be installed.

Therefore, during operation, a heating medium such as steam, hot water, or dowsam (hereinafter simply referred to as heating medium) introduced into the jacket cover 4 in order to heat the valve body 1 from the outside is connected to the left and right jacket covers. 4a, 4
From the introduction port 5a or 5b separately provided in b,
The liquid flows in the direction of the arrow in the left or right jacket cover 4a or 4b, respectively, and is discharged from separate outlets 6a or 6b.

(Problems to be solved by the invention) In the conventional jacket-type butterfly valve described above, the heat medium introduced into the jacket cover does not go around the valve body 1, but flows through each inlet and outlet. It will flow only between the holes and be discharged. Therefore, the heating efficiency of the neck portion 1a and the bottom portion 1b tended to decrease.

However, in the case of a fluid that solidifies at room temperature, the valve body will not operate smoothly unless the solidified fluid that has entered the area around the upper and lower valve stems, especially the gap between the valve stem and the bearing, is melted and fluidized by heating with a jacket and fluidized. There was a problem.

The technical problem of the present invention is to effectively exert the heating effect of the jacket on the neck and bottom of the valve body.

(Means for Solving the Problems) In order to solve the problems of the prior art described above, the present invention forms the valve body of a jacket type butterfly valve in a so-called wafer shape without flanges on both sides. A jacket cover is installed to cover the entire circumference of the valve body, including the neck and bottom.
The jacket cover is provided with one heat medium inlet on one side in a direction perpendicular to the flow direction across the valve stem axis, and one outlet on the other side in a direction facing the valve stem. , the heating medium is divided into two parts and flows through the neck and bottom of the valve body.

In addition, in actual practice, it is desirable to provide the heat medium inlet and outlet at substantially symmetrical positions with respect to the center of the valve body.

(Function) Since the present invention is constructed as described above, the heating medium is introduced in the direction facing the valve stem through the inlet provided on one side of the jacket cover across the valve stem axis, and a portion of the heat medium is introduced into the jacket cover in a direction facing the valve stem. The flow is divided into two directions, with the flow passing through the neck of the valve body and the rest passing through the bottom.
It flows out from an outlet provided on the other side across the valve stem axis in a direction facing the valve stem.

Therefore, the heat medium passes through the entire circumference of the wafer-shaped valve body without flanges, especially the neck and bottom, and flows as if circulating around the circumference of the valve body.
The heating effect is large, so the valve body operates smoothly.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

Figures 1a, b, and c are a front view, a side view, and a plan view showing a part (left half) of a jacket-type butterfly valve in cross section, showing an embodiment of the present invention. The same reference numerals as those shown in Figures 2a and b indicate the same or similar parts.

In the figure, 1 does not have a flange. A so-called wafer-shaped valve body includes a valve body 2 and a valve stem 3, and a jacket cover 14 is provided to cover the entire circumferential surface of the valve body 1, including the neck 1a and bottom 1b of the valve body 1. There is. That is, as shown in FIG. 1b, the jacket cover 14 is formed wider than the outer diameter of the valve stem support parts 3a and 3b, which correspond to the neck part 1a and the bottom part 1b of the wafer-shaped valve body, respectively. Welding 14b is performed between the circumferential surfaces of the rod supports 3a, 3b and both end surfaces of the jacket cover 14 to ensure a sufficient passage for the heat medium.

And on the circumferential surface of the jacket cover 14,
An inlet 15 and an outlet 16 for the heat medium are provided in the diametrical direction of the valve body 1, that is, in symmetrical positions with respect to the center. In addition, in the figure, 17 indicates a drain outlet.

With the above structure, during operation, the heat medium introduced from the inlet 15 in the direction of arrow a flows clockwise along the inside of the jacket cover 14, that is, the outer periphery of the valve body 1, as shown by arrow b. Then, the water flows counterclockwise as shown by arrow c, and flows into two, rejoining at the outlet 16 provided at a position substantially symmetrical to the inlet 15 with respect to the center, and flowing out to the outside. During this time, the heat medium heats the valve body 1 evenly, especially including the neck portion 1a and the bottom portion 1b, from the outer periphery.

Therefore, according to this embodiment, the fluid that has entered between the valve stem 3 and its bearing portion is also melted and fluidized by heating, so that the valve body 2 can operate smoothly.

Further, since only one piping is required for introducing and discharging the heat medium on each side, the cost of piping the valves to the actual device is reduced, and the piping work for installation and removal is also facilitated.

Further, since the valve body is formed in a so-called wafer shape without a flange, the valve body can be extremely lightweight and compact even if the outer periphery of the valve body is covered with a jacket cover.

In the above-described embodiments, the heat medium inlet 15 and outlet 16 are usually of the tapered female thread type for pipes, but depending on the piping, they may be of the tapered male thread type or the flange type.

Further, although a structure has been described in which the heat medium inlet and outlet are provided at diametrically symmetrical positions with respect to the center of the valve body, the positions of these two ports do not necessarily have to be symmetrical. In this case, the respective flow rates of the heating medium introduced from the inlet and then divided into the flow paths on both sides are not equal because they flow in inverse proportion to the fluid resistance (mainly fluid friction) of the respective flow paths.

(Effects of the invention) As explained above, according to the invention, the jacket cover of the jacket type butterfly valve is provided so as to cover the entire circumferential surface of the valve body including the neck and bottom, and the jacket cover In addition, by providing one heating medium inlet and one exhaust port on both sides of the valve stem in the direction opposite to the valve stem, the heating medium is distributed around the entire circumference of the valve body, especially in the upper and lower valves. It passes through the neck and bottom parts, which are equipped with a shaft support part, in two directions, and flows smoothly around the circumference of the valve body, so the valve body can be evenly heated from the outside. The thermal efficiency of the entire valve can be increased. In addition, the fluid that has entered between the valve stem and the bearing section is also fluidized by heating, so that the valve body can operate smoothly.

Further, since only one piping is required for introducing and discharging the heat medium on each side, the valve piping cost is reduced and the piping work for installation and removal becomes easy.

Further, since the valve body is formed into a wafer shape without a flange, the valve body can be extremely lightweight and compact even if the outer periphery of the valve body is covered with a jacket cover.

[Brief explanation of drawings]

Figures 1 a, b, and c are a partially sectional front view, side view, and plan view showing one embodiment of the present invention, and Figures 2 a and b are a partially sectional front view and side view showing a conventional example. . 1... Valve body, 1a... Neck, 1b... Bottom,
2... Valve body, 3... Valve stem, 14... Jacket cover, 15... Inlet, 16... Outlet.

Claims (1)

[Claims for Utility Model Registration] 1. Covering the outer peripheral surface of the valve body of a butterfly valve used for controlling fluids with high viscosity and fluids that crystallize and solidify at room temperature with a jacket cover,
In a jacket-type butterfly valve, which heats the valve body from the outside by passing a heat medium through the jacket cover to lower the viscosity of the fluid inside the valve and make it easier to flow, the valve body has a wafer shape without a flange. The jacket cover is provided to cover the entire circumferential surface of the valve body including the neck and bottom, and the jacket cover includes:
One heating medium inlet is provided on one side of the valve stem axis, and one outlet is provided on the other side in a direction facing the valve stem, so that the heating medium passes through the neck and bottom of the valve body. A jacket-type butterfly valve characterized by having a flow divided into two parts. 2. The jacket type butterfly valve according to claim 1, wherein the heat medium inlet and outlet are provided at substantially symmetrical positions with respect to the center of the valve body.