Low-pressure pipeline combined flange structure capable of shortening maintenance time

Abstract

A low-pressure pipeline combined flange structure capable of shortening maintenance time belongs to the technical field of low-pressure pipeline maintenance parts and is used for shortening the time for cutting off a low-pressure closed-loop pipeline. According to the technical scheme, the combined flange comprises two sets of combined flange pieces, each set of combined flange pieces is composed of three or four fan-shaped flange pieces, one end of the upper plane of each fan-shaped flange piece and the other end of the lower plane of each fan-shaped flange piece are respectively provided with a downward plane groove, and the depth of each plane groove is half of the thickness of each fan-shaped flange piece. The plane groove parts of the upper plane and the lower plane of each fan-shaped flange piece are respectively an upper lapping part and a lower lapping part, the middle part is a central part, three or four fan-shaped flange pieces are sequentially connected to form a circular ring, the upper lapping parts and the lower lapping parts of two adjacent fan-shaped flange pieces are lapped with each other, and the upper lapping parts and the lower lapping parts of the two adjacent fan-shaped flange pieces are lapped with each other. And three or four fan-shaped flange sheets are overlapped to form a ring-shaped flange. The device is simple in structure and convenient to use, maintenance time can be shortened, maintenance reliability is improved, and stable operation of the pipeline is guaranteed.

Description

Technical Field

[0001] The utility model relates to a combined flange structure which can shorten the time of cutting off a low-pressure closed-loop pipeline and realize rapid flange addition during pipeline emergency repair or reconstruction, and belongs to the technical field of low-pressure pipeline maintenance components. Background Art

[0002] Flanges are common components in pipeline equipment. Flanges are used to connect pipelines. They are easy to maintain, easy to disassemble and assemble, and have a wide pressure range. Flanges are used in pairs. There are holes on the plates. Gaskets are set between the two flanges. Bolts are passed through the holes to tighten them and press the gaskets to achieve sealing. The materials of pipeline flanges include carbon steel, low alloy steel, stainless steel, etc. Flanges are divided into threaded flanges, welding flanges and clamping flanges. Threaded flanges can be used for low-pressure pipelines, and welding flanges can be used for pressures higher than 0.4Mpa. Welding flanges are more common in actual applications.

[0003] Plate-type flat-welded flanges are often used for industrial medium transportation. In the event of an accident in a medium pipeline or in the transformation of a pipeline that is difficult to completely stop the medium, the medium can be cut off by removing the flange and adding a blind plate. This is convenient for construction and saves time for preparation. In industrial production that focuses on time efficiency, its value is particularly prominent. At present, when adding a welding flange to a low-pressure pipeline, it is necessary to first stop the medium transportation, then cut off the pipeline, weld flanges at the opposite ends of the cut pipeline, place and install the maintenance structure, and finally connect the two flanges with bolts to resume the medium transportation. This method requires the pipeline to stop transporting the medium in advance before welding, and the welding work takes a long time, so the time to stop transporting the medium is long, which has a great impact on some production processes. How to shorten the maintenance time and reduce the time the medium stops is an urgent problem to be solved. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a low-pressure pipeline combined flange structure which shortens the maintenance time. The combined flange structure can first weld the combined flange pieces when the low-pressure pipeline is repaired or modified, and then stop the medium delivery and cut off the pipeline after welding, so as to shorten the maintenance time and reduce the impact of stopping the medium delivery on production.

[0005] The technical solution to solve the above technical problems is:

[0006] A low-pressure pipeline combined flange structure that shortens maintenance time. The combined flange consists of three or four fan-shaped flanges. Each of the three or four fan-shaped flanges has a downward plane groove at one end of the upper plane and the other end of the lower plane. The plane groove is open on both sides and end faces of the upper plane and the lower plane. The depth of the plane groove is half the thickness of the fan-shaped flange. The plane groove parts of the upper plane and the lower plane of each fan-shaped flange are respectively an upper overlapping part and a lower overlapping part, and the middle is a central part. The lengths of the upper overlapping part, the central part and the lower overlapping part are respectively 1 / 3 of the fan-shaped flange. The three or four fan-shaped flanges are sequentially connected to form a circular ring. The upper overlapping parts and the lower overlapping parts of two adjacent fan-shaped flanges are overlapped with each other. The three or four fan-shaped flanges are overlapped to form a circular ring flange.

[0007] The above-mentioned low-pressure pipeline combined flange structure that shortens maintenance time, the upper overlapping part, the central part and the center of the lower overlapping part of the fan-shaped flange piece respectively have one or two screw holes, the screw holes of the upper overlapping part and the lower overlapping part of adjacent fan-shaped flange pieces are opposite, and the connecting bolts fasten the overlapping parts of two adjacent fan-shaped flange pieces through the relative screw holes of the upper overlapping part and the lower overlapping part.

[0008] The above-mentioned low-pressure pipeline combined flange structure that shortens the maintenance time comprises two groups of combined flanges, which are overlapped to form flanges. The inner holes of the two flanges are respectively welded to the outer peripheries of both ends of the pipeline maintenance part, and the screw holes in the central parts of the multiple fan-shaped flanges of the two groups of combined flanges welded on the pipeline are respectively connected to the maintenance parts through bolts.

[0009] The beneficial effects of the utility model are:

[0010] The combined flange structure of the utility model is composed of a plurality of fan-shaped flange pieces, which can be mounted on the outside of a pipeline and welded to the pipeline without cutting off the pipeline, thereby reducing the maintenance time of welding after cutting off the pipeline; the two ends of the plurality of fan-shaped flange pieces respectively have an upper overlap portion and a lower overlap portion, and the upper overlap portions and the lower overlap portions of adjacent fan-shaped flange pieces are relatively overlapped, so that the adjacent fan-shaped flange pieces can be firmly connected; after the two groups of combined flange pieces are welded to the pipeline and then the pipeline is cut off, replacement pipelines, blind plates, valves and other components can be placed and installed between the two groups of combined flange pieces, which is convenient for disassembly and assembly, and greatly saves maintenance time.

[0011] The utility model has a simple structure and is easy to use, and can realize the addition of a flange structure to the existing closed-loop pipeline without cutting off the pipeline, thereby adding a faster, more flexible and safer option for the reliable shutdown and delivery of non-toxic, non-flammable and non-high-temperature media, thereby shortening the maintenance time and increasing the maintenance reliability to ensure the stable operation of industrial enterprises, which is of great promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a top view of the three fan-shaped flange assembly after disassembly;

[0013] Figure 2 yes Figure 1 A side view of a fan-shaped flange;

[0014] Figure 3 yes Figure 1 A top view of the three fan-shaped flanges after being assembled;

[0015] Figure 4 This is a top view of the assembly of four fan-shaped flanges after disassembly;

[0016] Figure 5 yes Figure 4 Side view of a sector flange.

[0017] The markings in the figure are as follows: fan-shaped flange 1, upper overlapping part 2, central part 3, lower overlapping part 4, screw hole 5. DETAILED DESCRIPTION

[0018] The utility model is composed of a sector-shaped flange piece 1. A plurality of sector-shaped flange pieces 1 form two groups of combined flange pieces. Each group of combined flange pieces is composed of three or four sector-shaped flange pieces 1.

[0019] As shown in the figure, each of the three or four fan-shaped flanges 1 has a downward plane groove at one end of the upper plane and the other end of the lower plane, and the plane groove is open on both sides and end faces of the upper plane and the lower plane. The depth of the plane groove is half of the thickness of the fan-shaped flange 1. The plane groove parts of the upper plane and the lower plane of each fan-shaped flange 1 are an upper overlapping part 2 and a lower overlapping part 4, respectively, with a central part 3 in the middle. The lengths of the upper overlapping part 2, the central part 3 and the lower overlapping part 4 are respectively 1 / 3 of the fan-shaped flange 1.

[0020] As shown in the figure, there are one or two screw holes in the center of the upper overlapping part 2, the central part 3 and the lower overlapping part 4 of the fan-shaped flange 1 respectively, and the screw holes of the upper overlapping part 2 and the lower overlapping part 4 of adjacent fan-shaped flanges 1 are opposite to each other. The connecting bolts fasten the overlapping parts of two adjacent fan-shaped flanges 1 through the opposite screw holes of the upper overlapping part 2 and the lower overlapping part 4.

[0021] Figure 1 , 2 3 shows that three fan-shaped flanges 1 are sequentially connected to form a circular ring, and the upper overlap portion 2 and the lower overlap portion 4 of two adjacent fan-shaped flanges 1 overlap each other. The circular ring formed by overlapping the three fan-shaped flanges 1 is the same as the standard flange. The overall length of the arc of each fan-shaped flange 1 is the same as half of the flange formed, wherein half of the area of ​​the upper overlap portion 2 and the lower overlap portion 4 overlaps with the lower overlap portion 4 and the upper overlap portion 2 of another fan-shaped flange 1.

[0022] Figure 1 , 2 3 shows that there is a screw hole 5 in the center of the upper overlapping part 2, the central part 3 and the lower overlapping part 4 of the three fan-shaped flange pieces 1 respectively, and the connecting bolts fasten the overlapping parts of two adjacent fan-shaped flange pieces 1 through the relative screw holes 5 of the upper overlapping part 2 and the lower overlapping part 4.

[0023] Figure 4 , 5 It is shown that four fan-shaped flanges 1 are sequentially connected to form a circular ring, and the upper overlap part 2 and the lower overlap part 4 of two adjacent fan-shaped flanges 1 overlap each other. The circular ring formed by overlapping the four fan-shaped flanges 1 is the same as the standard flange. The overall length of the arc of each fan-shaped flange 1 is 3 / 8 of the flange formed, wherein half of the area of ​​the upper overlap part 2 and the lower overlap part 4 overlaps with the lower overlap part 4 and the upper overlap part 2 of another fan-shaped flange 1.

[0024] Figure 4 , 5 It is shown that there are two screw holes 5 in the center of the upper overlapping part 2, the central part 3 and the lower overlapping part 4 of the four fan-shaped flange pieces 1, and the connecting bolts fasten the overlapping parts of two adjacent fan-shaped flange pieces 1 through the relative screw holes 5 of the upper overlapping part 2 and the lower overlapping part 4.

[0025] The two groups of combined flanges of the utility model are overlapped to form flanges, the inner holes of the two flanges are respectively welded to the outer peripheries of the two ends of the pipeline maintenance part, and the screw holes of the central parts 3 of the multiple fan-shaped flanges 1 of the two groups of combined flanges welded on the pipeline are respectively connected to the maintenance parts through bolts.

[0026] The use process of the utility model is as follows: (taking the replacement of a leaking pipeline as an example)

[0027] The first step is to prepare two sets of fan-shaped flanges 1 that match the pipeline to be constructed, and clean the surface of the leaking pipeline;

[0028] The second step is to select the intact positions of the upstream and downstream pipelines of the leakage site and weld the fan-shaped flanges 1 respectively. After completing the welding of one fan-shaped flange 1, fix the screw holes 5 of the overlapping part with bolts and then weld the other fan-shaped flange 1 to ensure that the fan-shaped flanges 1 are tightly combined;

[0029] The third step is to prepare a prefabricated pipe section for welding, and connect the two ends of the prefabricated pipe section to weld a standard movable flange that matches the fan-shaped flange piece 1;

[0030] Step 4: After all prefabrication and preparation are completed, the valves are closed to stop water flow to the pipeline, and water is discharged after the valve to reduce pressure;

[0031] Step 5: Cut the damaged pipe between the two sets of fan-shaped flanges 1 after the pressure is reduced, and grind the joint with the fan-shaped flanges to make it smooth;

[0032] Step 6: Install the prefabricated pipe section, add the sealing gasket, adjust the screw holes of the movable flange, and tighten the bolts;

[0033] Step 7. Slowly restore water supply.

[0034] The water outage time in the above implementation process is nearly 2 / 3 shorter than the normal emergency repair time. The water outage in this application is about 2 hours in total, and the prefabricated pipe joints are fixed by bolts, which can be operated with water, with fewer operation restrictions and wider applicability. Compared with the pressure plugging operation, the utility model has low use cost, more reliable thorough repair effect, and greater application value under specific conditions.

[0035] An embodiment of the present utility model is as follows:

[0036] Four sector-shaped flanges 1 are used, each of which has an arc angle of 67.5 degrees, wherein the arc angles of the upper portion 2, the central portion 3 and the lower portion 4 are 22.5 degrees respectively;

[0037] The dimensions of the complete flange after overlapping are:

[0038] Outer diameter 560mm, screw hole distance 515mm, number of screw holes 16, weight approximately 45kg, thickness 60mm.

Claims

1. A low-pressure pipeline combined flange structure that shortens maintenance time, characterized in that: The combined flange is composed of three or four fan-shaped flanges (1). Each of the three or four fan-shaped flanges (1) has a downwardly directed plane groove at one end of the upper plane and the other end of the lower plane. The plane groove is open on both sides and end faces of the upper plane and the lower plane. The depth of the plane groove is half the thickness of the fan-shaped flange (1). The plane grooves of the upper plane and the lower plane of each fan-shaped flange (1) are respectively an upper overlap part (2) and a lower overlap part (4), with a central part (3) in the middle. The lengths of the upper overlap part (2), the central part (3) and the lower overlap part (4) are respectively 1 / 3 of the fan-shaped flange (1). The three or four fan-shaped flanges (1) are sequentially connected to form a circular ring. The upper overlap parts (2) and the lower overlap parts (4) of two adjacent fan-shaped flanges (1) are overlapped with each other. The three or four fan-shaped flanges (1) are overlapped to form a circular ring flange.

2. The low-pressure pipeline combined flange structure for shortening maintenance time according to claim 1 is characterized in that: The upper overlapping portion (2), the central portion (3) and the lower overlapping portion (4) of the fan-shaped flange (1) are respectively provided with one or two screw holes (5) in the center. The screw holes (5) of the upper overlapping portion (2) and the lower overlapping portion (4) of adjacent fan-shaped flanges (1) are opposite to each other. The connecting bolts fasten the overlapping portions of the two adjacent fan-shaped flanges (1) through the opposite screw holes (5) of the upper overlapping portion (2) and the lower overlapping portion (4).

3. The low-pressure pipeline combined flange structure for shortening maintenance time according to claim 2 is characterized in that: The combined flanges are in two groups, and the two groups of combined flanges are overlapped to form flanges. The inner holes of the two flanges are respectively welded to the outer peripheries of both ends of the pipeline maintenance part, and the screw holes (5) of the central parts (3) of the multiple fan-shaped flanges (1) of the two groups of combined flanges welded on the pipeline are respectively connected to the maintenance parts by bolts.

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