JPS6093203A - Collision porous plate with projection and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a perforated impingement plate with protrusions for a moisture separating heater in a steam generator and a method for manufacturing the same.

The driving steam for steam turbines, etc. is required to be as dry as possible for various reasons, so it is necessary to remove moisture by subjecting the steam containing minute water droplets obtained from the steam generator to a moisture fractionator. However, in the first stage of the moisture/heater, an impingement perforated plate 1 having a protrusion 3 from which 20 steam passage holes protrude around 20 as shown in FIG. 1 is used. The protrusion is provided to prevent minute water droplets from accumulating on the surface of the perforated plate 1 and forming a water film from being sent downstream from the steam passage hole 2 again. As shown in FIG. 2, there is a conventional example in which the protrusion is formed into a conical protrusion 3a whose outer periphery increases in diameter as the distance from the perforated plate surface increases. In the plate 1, the initial steam flow 4a collides with the perforated plate together with the minute water droplets 4b contained therein, a part of which is a steam flow 4d directed into the passage hole, and the other part is a steam vi1 along the end surface of the protrusion. .4 e, and the other part is γ on the side surface of the protrusion.
After being divided into swirling steam flows 4f, water droplets are eventually removed and the steam 4c is sent out of the collision perforated plate 1 from the steam passage hole 2. The water film flow 5 that accumulates on the plate surface flows downward due to gravity and scatters as water droplets 6 from the lower part of the outer periphery of the end surface of the protrusion, and then enters the passage hole 2 through the water droplet scattering path 7. It is said that the ability to separate moisture is not necessarily high because it becomes scattered water droplets 8 and comes out of the board.

A detailed analysis and examination of the behavior of the steam flow 4a around the conical protrusion 3a reveals that the steam flow is divided into the steam flow 4d, the steam flow 4e, and the swirling steam flow 4f. The steam flow 4e along the end surface of the protrusion and the swirling steam flow 4f along the side surface of the protrusion form a combined steam flow, and the steam flow causes the scattered water droplets 6 that have left the tip of the protrusion to pass through the scattering path 7 and become one stage. It enters the lower passage hole 2 and gets mixed in, thereby reducing the moisture separation ability.

The present invention has been made in view of the current situation, and is achieved by cutting out at least the lower half of the periphery of the protruding end of the conical protrusion whose diameter increases as the distance from the plate surface of the collision perforated plate increases. It is an object of the present invention to provide a perforated impingement plate with protrusions for a moisture separating heater that eliminates structural defects and a manufacturing method.

Next, to explain an embodiment of the present invention with reference to the drawings, in FIG. Therefore, the diameter is increased, and a conical protrusion 3b with a circumferential notch 3c cut out from the periphery of the end of the protrusion is provided.

Therefore, according to the present invention, when the steam flow 4a containing minute water droplets 4b collides with the perforated plate 1 according to the present invention, the steam flow 4d enters the steam passage hole 2.

Steam flow 4g toward the periphery of the bottom end of the protrusion and the protrusion 411
The water film flow 5, which is divided into the air flow 4f and accumulates on the plate surface between each adjacent protrusion, is prevented by arranging a circumferential notch 3c on the periphery of the protrusion end of the protrusion. Since it is a set-up, it is not formed at the notch part, and is not formed on the circumferential side of the protrusion and the plate surface between the adjacent protrusion parts except for the above-mentioned part.
The scattered and dripping water droplets 9 in the portion of the water film flow close to the notch are the steam flow 4g and the swirling steam flow 4.
Since the merged steam flow of f flows vertically downward or toward the plate surface, it flows through the water droplet transfer path 10 and does not come out in front of the opening of the lower passage hole 2, which prevents the water droplet from flowing. Since the moisture does not enter the passage holes and hangs down at the lowest end of the perforated plate 1, the moisture separation ability is greatly improved. In addition, in Fig. 3, to is (!I the thickness of the perforated hole plate, 11 is the total height of the conical protrusion: 31), 1]
d indicates the height of the droplet 9 from the plate surface, and it is clear that hd is smaller than h as described above. Further, D indicates the diameter of the steam passage hole 2.

To explain the manufacturing method of integrally molding the perforated impact plate with protrusions according to the present invention described above from the perforated impact plate 1 as its substrate, first, as shown in FIG. 4(a), the thickness t. A passage hole 11 having a predetermined inner diameter and leaving a bottom portion 12 thick toward the center of the inner diameter is separately formed at a predetermined position on the substrate using a processing tool such as an end mill or a candle-shaped drill. Then, as shown in FIG. 4(b), a funnel-shaped through hole 13 of a predetermined size is bored from the back surface of the bottom part, and an angled top part 14 is formed at the corner of the plate surface. Then, as shown in FIG. 4(c), the bottom part 12 of the passage hole is made to protrude in a crater shape to form a protrusion 15 using a rotary tool whose tip is shaped like a cannonball and the tip is conical. As shown in FIG. 4(d), when the inner diameter of the raw hole 11 is finished to the same diameter over the entire length of the hole using the cylindrical part of the rotary tool or using a pipe expander or the like, A circumferential notch 3c is formed on the periphery of the end of the protrusion, and a conical raised part 3b is formed with the notched top part 14, and the total length of the passage hole 2 at this time is equal to the thickness of the substrate. t. The total height of the protrusions 11 is added to the total height of the protrusions, and the height I+d of the plate surface of the protrusion apex 14 becomes smaller than 11, so that the protrusion perforated plate according to the above-mentioned embodiment is manufactured.

Next, the embodiments of the 4-protrusion/IiI-protrusion plate/hole plate according to the present invention will be described.
In o), the steam J- in the steam passage hole 2 of the collision perforated plate l
On the flow side plate surface, around the passage hole and away from the plate surface/
A crescent-shaped notch 3d is formed by cutting out the lower half of the protruding end, and a conical protrusion 3g is protruded from the crescent-shaped notch. It goes without saying that the effect is the same as in the previous embodiment, and the manufacturing method is as follows: : It is best to turn it in a January shape as shown in Figure 5 (b).

Still another embodiment of the collision perforated plate according to the present invention shown in FIG. Therefore, when the outer diameter is expanded in a rasp-like shape, a rasp-like protrusion 3f is protruded, and the height hd of the protrusion to the plate surface side is greater than the entire protrusion A h. By forming the protrusion into a small size, the effect is similar to that of the two embodiments described above, and this is conventionally achieved by thinning the protrusion and then expanding the diameter into a desired rabbet shape.

Although each of the above embodiments has been described using a moisture splitting heater of a steam generator having a perforated plate impinging on the protrusions (d), it can also be applied to a tube plate of a heat exchanger having heat exchange tubes. In the conventional structure, as shown in FIG. 7(A), a protrusion 3 is formed around a passage hole 2 formed in a perforated plate 1, and a heat exchange tube 15 is inserted and fitted into the passage hole. After that, the end face of the protrusion and the outer periphery of the heat exchange tube are brazed or welded to form part 16.
However, since the thickness of the protrusion is generally larger than the thickness of the tube, there is a significant difference in heat capacity, and the clearance 16a in the gap between the heat exchange tube and the protrusion is It has the disadvantage of generating defective parts. However, if the protrusion structure according to the present invention is applied, the circumferential notch 3C is formed at the tip of the conical protrusion 3b.
Since the tip wall thickness can be reduced in accordance with the pipe wall thickness, the solder ring is formed in the main part so that the solder ring 161 between the pipe and the protrusion is formed in the main part. Heating during processing can be made the same. Note that even when welding is used, it is not true that the weld penetration becomes deeper and the adhesiveness improves.

As described above, the present invention has great industrial utility because it can eliminate the drawbacks of the prior art with an extremely simple and easy-to-clean structure and manufacturing method.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional side view of the main part of a conventional perforated impingement plate for a moisture fractionator of a steam generator, and Fig. 2 is an enlarged longitudinal cross-sectional view of the main part of a conventional perforated perforated impingement plate equipped with a circular external protrusion. Side view, Figure 3]2.
A vertical cross-sectional view of main parts showing an embodiment of this invention, FIG. 4(A),
(b), (c), and (d) are enlarged longitudinal sectional side views of the pleasant part showing the method for manufacturing the notched conical protrusion according to the present invention, and FIG. FIG. 5 (b) is a longitudinal sectional side view of the main part showing the embodiment. -1, also a plan view of the main part, FIG. 6 is a longitudinal sectional side view of the main part showing still another embodiment of the present invention, and FIG. 7 (a) shows a conventional heat exchange tube inserted into a perforated plate. FIG. 7(b) is a vertical sectional side view of the main part showing the retaining part of the tube and plate in the heat exchanger which has been used in the present invention. FIG. 1... Collision perforated plate, 2... Steam passage hole, 3b... Notch conical protrusion, 3C... Circumferential notch, 3d... Crescent-shaped notch, 3f... Radha-shaped protrusion , 3g...Crescent-shaped notch, number of conical protrusions, 11...Path hole, 1
2. Bottom, 13. Funnel-shaped through hole, 14. Shaped top 15. Protrusion. Figure 1 Figure 2 Figure 4-Figure

Claims (1)

[Claims] (1) A conical protrusion whose diameter increases as the distance from the plate surface increases around the passage hole is provided protrudingly on the upstream side plate surface of the air passage hole of the multi-projection plate hole, and the protrusion end of the protrusion A collision perforated plate with protrusions for a moisture splitter heating device, characterized in that a notch is provided in at least the lower half of the periphery. A collision perforated plate with protrusions for a moisture/heater, characterized in that the outer diameter increases in the shape of a ridge as it is separated from the other, and has a ridge-like protrusion projecting thereon. 3) A funnel in which a passage hole is separately provided while leaving a thick bottom part formed toward the center of the board, and then a 2-shaped top part is formed from the back of the bottom part to the corner of the plate surface. After drilling a through hole in the shape of a shape, the bottom of the hole is made to protrude in the shape of a crater, and the inner diameter of the hole is rounded to the same diameter over the entire length of the hole. A method for producing a collision perforated plate with protrusions for a moisture-separating heating device.