KR950012432B1 - Bucket type strainer and the manufacturing process - Google Patents

Abstract

The steel strainer for filtering the foreign materials mixed in the liquid flow of the pipeline in the oil refinery or chemical plant, comprises the protrudent section(12a) for connecting the pipe connecting section(11) at the both curved sections of the strainer section(12); pipe connecting section(11) welded to the protrudent section; horizontal filtering net seat(14a) loading the filtering net(13) in the section(12) and vertical flow induction section(14b) for inducting the liquid from the seat(14a) to the upper side; cylindrical filtering net(13) having a lot of unit openings against the liquid inflow section.

Description

Bucket type strainer and its manufacturing method

1 is a front view of a conventional bucket type strainer.

2 is a cross-sectional view of a conventional bucket type strainer.

3 is a perspective view of a bucket type strainer of the present invention.

4 is a cross-sectional view of the bucket type strainer of the present invention.

5 is a cross-sectional view taken along the line A-A in FIG.

6A to G are manufacturing process drawings of the bucket type strainer of the present invention.

＊ Explanation of symbols for main parts of drawing

1: pipe connection part 2: filtration part

3: filter network 4: filter network sheet

11 pipe connection 12 filter part

12a: protrusion 12b: flange

12c: lower cover 13: filter network

14: filter network sheet and inflow guide 14a: filter network sheet

14b: inflow guide 15: support

15a: band 16: filter cover

20: small hole 21: mold

22: connecting rod 23: hydraulic cylinder (or pneumatic cylinder)

[Field of Invention]

The present invention relates to a strainer for filtering foreign substances mixed in a fluid flowing into a pump in order to protect pumps installed in various pipes and subsequent peripheral devices in a manufacturing process such as an oil refinery or a petrochemical plant. In particular, it relates to a bucket type strainer made of steel which is simple in manufacturing (especially welding) and has excellent filtration performance, and a method of manufacturing the same.

[Background of invention]

Strainers for filtering foreign substances in the fluid flowing through the pipe structure include bucket type strainers, y type strainers, and the casings are made of steel and manufactured by casting.

Bucket type or Y type is appropriately selected depending on the installation location and flow conditions. Among the bucket type strainers, the casing is manufactured by casting, and since most pipes are made of steel, mechanical characteristics such as strength do not coincide with the pipes, so there is a problem that the pressure limit should be taken into consideration when designing. In addition, there is a problem in that it is not more beautiful than steel and does not coincide with the appearance (surface roughness) of the pipe. Therefore, steel strainers are used more than strainers manufactured by casting.

In the conventional bucket type strainer made of steel, as shown in FIGS. 1 and 2, the left and right pipe joints 1 are welded to the cylindrical filtration unit 2, and the side valleys of the filtration unit 2 are shown. Since the end of the pipe connection part 1 is welded on the surface, it is very difficult to cut the pipe so that the side curved surface of the filter part 2 and the end of the pipe connection part 1 are closely connected to the welding line. Due to the line contact rather than contacting, there is a problem that the welding operation is very difficult, such as external welding and internal welding to increase the welding strength.

On the other hand, the performance of the strainer is determined by the opening ratio of the filtering net 3, which means the opening area of the filtering net 3 with respect to the cross-sectional area of the inlet (or outlet) of the pipe connection 1. If the opening area of the filtering net is smaller than the inlet cross-sectional area of the pipe connection 1, the fluid flow will be disturbed.

And if the opening ratio is 150%, if the hole of the filter network is blocked by 1/3, the fluid flow will be disturbed. Therefore, the filter net must be replaced or cleaned. Therefore, the higher the opening ratio, the better. By the way, the area of the unit opening of a filter net cannot be enlarged in order to raise an aperture ratio. This is because the area of the unit opening is predetermined according to the size of the foreign matter to be filtered. Therefore, in order to increase the opening ratio of the filtering network, the ratio of the number of unit openings to the cross-sectional area of the inlet (outlet) must be set.

However, in the conventional bucket type strainer, as shown in FIG. 2, the filter net sheet 4 is inclined, and the filter net 3 is not a cylindrical shape but a part of the upper part of the inlet side is cut. Therefore, the conventional filter net 3 has a smaller number of unit openings corresponding to the cut area than the case of a completely cylindrical shape, and the opening ratio is also low. Therefore, the conventional bucket type strainer has a problem in that the filter net 3 must be replaced or cleaned frequently.

In addition, the conventional bucket type strainer also has a problem that the filtration performance is lowered because the filter net sheet 4 is inclined so that the airtightness between the filter net 3 and the filter net sheet 4 is not completely maintained.

[Purpose of invention]

The present invention has been made in order to solve the problems of the conventional bucket type strainer described above, it is easy to weld the pipe connection portion and the filter portion, the opening ratio is high, and the airtightness between the filter net and the filter sheet is improved bucket type strainer improved filtration performance And it aims at providing the manufacturing method.

[Summary of invention]

In order to achieve the above object, the present invention provides a projection unit integrally formed on both sides of the filtration section by a special method so that the pipe connection section can be easily welded, and the pipe connection section is welded to the projection section of the filtration section. The unit of the filtering network with respect to the fluid inflow cross-sectional area, since the filtering network sheet having a horizontal filter net sheet to be installed and a vertical inflow guide unit for introducing the introduced fluid to the upper part and the inflow guide unit are formed inside and the filter network is completely cylindrical. It is characterized by a bucket type strainer having a large numerical aperture and improved airtightness between the filter net and the filter net sheet, and a method of manufacturing the same.

[Description of Specific Embodiment of the Invention]

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Bucket type strainer of the present invention, as shown in Figures 3 to 5, the projection portion 12a is formed integrally so that the pipe connection portion 11 can be easily welded to both side surfaces of the filter portion 12 The pipe connection part 11 is welded to the projection part 12a of the said filtration part 12, and the horizontal filtration net sheet | seat 14a and the fluid which flowed in which the filtration net 13 is installed in the filtration part 12 are installed. Is composed of a filter net sheet and an inlet guide portion 14 composed of a vertical inlet guide portion 14b for directing the upper portion thereof. The support 15 is not fixed to the filtration part 12, but the band 15a is comprised in the upper part, and is connected to the filtration part 12 by a bolt and a nut.

Bucket type strainer of the present invention as described above is manufactured by the following procedure.

1) In order to form the filtration part 12 with the projection part 12a, the part of the steel pipe in which the projection part 12a is to be formed is partially heated, and then the small hole 20 is drilled and it is shown in FIG. 6 (a). As described above, the mold 21 having the same outer diameter as the inner diameter of the protrusion 12a is positioned inside the steel pipe, and the connecting rod 22 connected to the mold 21 passes through the small hole 20 so that the hydraulic pressure is applied to the connecting rod 22. Connecting the cylinder (or pneumatic cylinder) 23, and moving the mold 21 to the outside of the steel pipe by the hydraulic cylinder 23 to form the projection as shown by the dashed line, 2) FIG. 6 (b) ), The process of forming the projection in the opposite position in the same manner as the process 1), 3) in the process 1), 2), as shown in Figure 6 (c) Cutting the ends of the formed projections on both sides to complete the projections 12a, 4) as shown in FIG. As shown in Fig. 6 (e), the process of welding the pipe joints 11 to the both side projections 12 as shown in FIG. Process of welding the filtering net sheet and the inflow guide 14 of the induction part 14b, 6) As shown in FIG. 6 (f), the flange part 12b is welded to the upper part of the steel pipe, and the lower part to the lower part. Process of welding the lid 12c, 7) As shown in FIGS. 4 and 6 (g), tighten the bolts and nuts by inserting the filtration part 12 into the band 15a of the support 15. By connecting the filtration unit 12 and the supporter 15, and installing the filtration net 13 in the filtration net sheet 14a, and then assembling the filtration unit cover 16 on the filtration unit 12 by bolts. .

Since the procedures of the above processes can be partially changed, it can be known to those skilled in the art, and thus the description of the modified examples will be omitted.

Hereinafter, the operation and effect of the bucket type strainer of the present invention manufactured by the above procedure will be described.

The fluid flows into the filtration unit 12 through the inlet 11 and flows upward through the filtration network sheet 14a by the induction guide 14b, and then through the opening of the filtration network sheet 14a. (13) After entering the inside, it passes through the filtering net 13 and flows outside the filtering net 13. The fluid outside the filtering net 13 flows out through the conduit 11 on the outlet side.

Bucket type strainer of the present invention is to cut the side surface of the filter portion 12 as in the prior art in order to weld the pipe connection portion 11 and the filter portion 12, and the end of the pipe connection portion 11, the filter portion 12 Rather than the tricky procedure of cutting to fit the cut surface of), the protrusion 12a protruding from the side curved surface of the filtering portion 12 is formed so that the junction of the filtering portion 12 and the pipe connection portion 11 is coplanar. Because it is in phase, welding is very easy and the welding surface is completely close, so even if it is welded only from the outside, a large welding strength can be obtained.

In addition, the present invention can make the filter net sheet 13 and the inlet and inlet portion 14 of the filter net 13 in the shape of a completely cylindrical, so as to increase the opening area of the filter net 13 compared to the inlet and outlet cross-sectional area of the pipe connection (11). Can be. Therefore, the present invention is excellent in filtration performance because the opening ratio (total opening area of the filtering net with respect to the inlet cross-sectional area) of the filtering net 13 is large. That is, even if foreign matters are somewhat accumulated in the filtration net 13 by the filtration action, the filtration action can be performed for a long time without affecting the flow of the fluid. In addition, since the filtering net sheet 14a is horizontal, the airtightness is improved between the filtering net 13 and the filtering net sheet 14a, so that the fluid always passes through the filtering net 13. That is, the filtration performance is improved.

On the other hand, in the present invention, since the filtration unit 12 and the support 15 are not fixed, the height of the pipe connection part 11 can be appropriately adjusted according to the pipe height when assembling the pipe. In other words, by loosening the bolts and nuts for fastening the band (15a) to adjust the height of the pipe connection (11) and then refasten it can be easily installed in a variety of installation conditions.

Claims (3)

In the bucket-type strainer made of steel for filtering foreign matter mixed in the fluid in the piping structure, the projections 12a are integrally formed so as to easily weld the pipe connecting portion 11 to both curved surfaces of the filtering portion 12. It is formed, and the pipe connecting portion 11 is welded to the projection (12a) of the filtration unit 12, and the filtration network sheet 14a is introduced into the filtration unit 12 and the horizontal filtration network sheet 14a is installed The filter net sheet and hydraulic induction part 14 which consist of the vertical inflow guide part 14b which guides a fluid to the upper part are comprised, and the filter net 13 is a completely cylindrical shape, and the unit opening of the filter net 13 with respect to a fluid inflow cross-sectional area is shown. Bucket type strainer characterized by the large number. The bucket type strainer according to claim 1, wherein a band (15a) is formed on the upper portion, and a support (15) connected to the filtration part (12) by a bolt and a nut is further configured. In the method of manufacturing a bucket-type strainer, which includes a pipe connection part 11 and a filter part 12, which is installed in a pipe structure and filters foreign substances mixed in the fluid, the pipe connection part 11 and the filter part 12 are welded. In order to partially heat the portion of the steel pipe in which the protrusions 12a are to be formed, drill a small hole 20, and place a mold 21 having an outer diameter equal to the inner diameter of the protrusion 12a in the steel pipe. To connect the hydraulic cylinder (or pneumatic cylinder) 23 to the connecting rod 22 so that the connecting rod connected to the small hole 20 penetrates, and moves the mold 21 out of the steel pipe by the hydraulic cylinder 23. And a step of forming a protrusion, and a step of cutting the end of the protrusion formed in the process to complete the protrusion (12a).