Header structure capable of preventing header pipe base from cracking
By using a split design and a telescopic mechanism in the header structure, the problem of weld cracking caused by thermal expansion differences in the header tube seat was solved, stress dispersion and compensation were achieved, and the safety of the boiler was improved.
Patent Information
- Application Number
- CN202520689346.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-11
- Publication Date
- 2026-02-06
- Estimated Expiration
- 2035-04-11
AI Technical Summary
Thermal stress concentration caused by the difference in the coefficient of thermal expansion of the header pipe seat leads to weld cracking, which is more pronounced at both ends of long headers.
The header structure adopts a split design, with the main body and the auxiliary body of the header connected by a telescopic mechanism. Combined with the telescopic mechanism of the bellows and slide rod, it absorbs and disperses the stress generated by the difference in thermal expansion. The stress is dispersed by the annular groove and the chamfer, reducing stress concentration.
It effectively disperses and alleviates stress concentration caused by differences in thermal expansion, reduces the risk of cracking in the header tube seat weld, and improves the safety and reliability of the boiler.
Smart Images
Figure CN223882179U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the technical field of boiler header, especially relates to a header structure for preventing cracks of header pipe seat. BACKGROUND
[0002] At present, the problem of header pipe seat weld cracking has become a hidden danger affecting the safe operation of the boiler. The main reason is that there is a difference in the thermal expansion coefficients of the header and the pipe bundle arranged thereon. During the operation of the boiler, the header and the pipe bundle will expand or contract due to temperature changes. Due to the difference in thermal expansion coefficients, the deformation amounts of the two are inconsistent, thereby generating thermal stress at the pipe bundle and the header pipe seat. When the thermal stress exceeds the ultimate strength of the header pipe seat weld, the weld will crack. In particular, the longer the header, the more concentrated the stress generated at both ends due to the difference in thermal expansion, and the higher the risk of cracking. SUMMARY
[0003] The utility model discloses a kind of header structures for preventing cracks of header pipe seat, to solve the problem that the above-mentioned thermal stress concentrates on pipe seat weld and leads to weld cracking.
[0004] To achieve the above object, the utility model provides the following scheme:
[0005] A kind of header structure for preventing cracks of header pipe seat, comprising: header main body, the both ends of the header main body are provided with header auxiliary body respectively, the header auxiliary body is communicated with the header main body by telescopic mechanism;
[0006] Second water-cooled wall pipe is communicated on the header main body, first water-cooled wall pipe is communicated on the header auxiliary body, outlet structure is communicated on the header main body.
[0007] Preferably, the telescopic mechanism includes bellows, the both ends of the bellows are respectively fixedly connected with first flange, sliding member is slidably connected between two first flanges.
[0008] Preferably, the sliding member includes multiple slide rods, multiple slide rods are coaxially arranged with the bellows, multiple slide rods are circumferentially equidistantly arranged, and the end portion of the slide rod penetrates out of the first flange and is fixedly connected with limiting piece.
[0009] Preferably, second flange is fixedly connected on the header main body and the header auxiliary body, and the second flange is fixedly connected with the first flange.
[0010] Preferably, the first water-cooled wall pipe is communicated with the header auxiliary body through through-hole, and the through-hole is arranged on the header auxiliary body.
[0011] Preferably, an annular groove is coaxially arranged at the outer edge of the through hole and is formed on the header sub-body.
[0012] Preferably, an inner chamfer is formed at one end of the through hole and is located on the outer sidewall of the header sub-body, and an outer chamfer is formed at one end of the first water cooling wall pipe, and the inner chamfer is matched with the outer chamfer.
[0013] Preferably, an expansion compensation part is arranged on the first water cooling wall pipe.
[0014] Preferably, the expansion compensation part comprises an expansion elbow, and a water outlet end of the expansion elbow is communicated with the first water cooling wall pipe.
[0015] Preferably, the outlet structure comprises an outlet connecting pipe, one end of the outlet connecting pipe is communicated with the header main body, and the other end of the outlet connecting pipe is connected with a steam-water separator.
[0016] Compared with the prior art, the utility model has the advantages and technical effects as follows:
[0017] In the utility model, the header is divided into a header main body and a header sub-body, stress concentration caused by thermal expansion difference at two ends of the header can be adjusted by the split type design, a certain thermal expansion displacement between the header main body and the header sub-body can be adjusted by the telescopic mechanism, the stress concentration caused by thermal expansion difference at two ends of the header can be dispersed and relieved by the telescopic mechanism, after absorbing heat, the steam-water mixture in the first water cooling wall pipe and the second water cooling wall pipe can enter the header main body and the header sub-body respectively, the steam-water mixture mixed in the header main body and the header sub-body can be transported to the outside by the outlet structure communicated with the header main body. BRIEF DESCRIPTION OF DRAWINGS
[0018] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiments will be briefly introduced as follows, and obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained by those skilled in the art without creative labor under the premise of the drawings:
[0019] Figure 1 It is a structural schematic view of the utility model;
[0020] Figure 2 It is Figure 1 It is a local enlarged view of A in the middle;
[0021] Figure 3 It is Figure 1 It is a local enlarged view of B in the middle;
[0022] Wherein, 1, header main body; 2, header auxiliary body; 3, outlet connecting pipe; 41, bellows; 42, first flange; 43, second flange; 44, sliding rod; 5, first water wall pipe; 6, expansion bend; 7, second water wall pipe; 8, annular groove. DETAILED DESCRIPTION
[0023] The technical solutions in the embodiments of the utility model will be apparently and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.
[0024] In order to make the above-mentioned purposes, features and advantages of the utility model more apparent, obvious and easy to understand, the utility model will be further described in detail below with reference to the drawings and specific embodiments.
[0025] Reference Figures 1 to 3 The utility model discloses a kind of header structure for preventing crack of header pipe seat, comprising: header main body 1, the both ends of header main body 1 are provided with header auxiliary body 2, header auxiliary body 2 is communicated with header main body 1 by telescopic mechanism;
[0026] Header main body 1 is communicated with several second water wall pipes 7, header auxiliary body 2 is communicated with several first water wall pipes 5, and header main body 1 is communicated with outlet structure.
[0027] Header is divided into header main body 1 and header auxiliary body 2, to adjust the stress concentration generated by thermal expansion difference of two ends of header with split design, certain thermal expansion displacement exists between header main body 1 and header auxiliary body 2 by telescopic mechanism connection, stress concentration generated by thermal expansion difference of two ends of header can be dispersed and relieved by telescopic mechanism, after absorbing heat, the internal steam-water mixture of first water wall pipe 5 and second water wall pipe 7 can enter header main body 1 and header auxiliary body 2 respectively.
[0028] Further optimization scheme, telescopic mechanism includes bellows 41, the both ends of bellows 41 are fixedly connected with first flange 42, and sliding member is slidably connected between two first flanges 42.
[0029] Further optimization scheme, sliding member includes multiple sliding rods 44, multiple sliding rods 44 are coaxially arranged with bellows 41, multiple sliding rods 44 are circumferentially equidistantly arranged, and the end portion of sliding rod 44 penetrates out of first flange 42 and is fixedly connected with limiting piece.
[0030] Further optimization scheme, second flange 43 is fixedly connected on header main body 1 and header auxiliary body 2, and second flange 43 is fixedly connected with first flange 42.
[0031] The header main body 1 and the header auxiliary body 2 can expand in all directions, and the expansion and contraction mechanism can expand and contract like a spring through the cooperation of the bellows 41 and the slide rod 44. The elasticity and the expansion and contraction of the expansion and contraction mechanism can absorb and compensate the thermal expansion displacement between the header main body 1 and the header auxiliary body 2.
[0032] In a further optimization scheme, the first water cooling wall pipe 5 is in communication with the header auxiliary body 2 through a through hole, and the through hole is arranged on the header auxiliary body 2.
[0033] The first water cooling wall pipe 5 is welded on the header auxiliary body 2 and in communication with the through hole.
[0034] In a further optimization scheme, a ring groove 8 is coaxially arranged at the outer edge of the through hole, and the ring groove 8 is arranged on the header auxiliary body 2.
[0035] The ring groove 8 provides a certain deformation allowance for the welding area, and the expansion and contraction will not directly act on the welding point. At the same time, when the welding area is subjected to thermal stress, the stress can be dispersed along the circumferential direction of the ring groove, rather than concentrated on the welding point itself.
[0036] In a further optimization scheme, one end of the through hole is provided with an inner chamfer, and the inner chamfer is located on the outer side wall of the header auxiliary body 2. One end of the first water cooling wall pipe 5 is provided with an outer chamfer, and the inner chamfer is matched with the outer chamfer.
[0037] The matching of the inner chamfer and the outer chamfer can disperse the stress to a larger area, reduce the accumulation of stress in a local position, and thus reduce the stress concentration coefficient.
[0038] In a further optimization scheme, the first water cooling wall pipe 5 is provided with an expansion compensation part.
[0039] In a further optimization scheme, the expansion compensation part includes an expansion elbow 6, and the water outlet end of the expansion elbow 6 is communicated with the first water cooling wall pipe 5.
[0040] In a further optimization scheme, the outlet structure includes an outlet connecting pipe 3, and the other end of the outlet connecting pipe 3 is connected with the steam-water separator.
[0041] The working process of the embodiment is as follows:
[0042] The lower end of the first water cooling wall pipe 5 and the lower end of the second water cooling wall pipe 7 are used to absorb the heat radiation of the industrial boiler, the water in the pipe is evaporated to form a steam-water mixture after being heated, the steam-water mixture flows upward after the density is reduced after being heated, the steam-water mixture output by the first water cooling wall pipe 5 and the second water cooling wall pipe 7 is collected by the header main body 1 and the header auxiliary body 2, and the steam-water mixture is transported to the steam-water separator through the outlet connecting pipe 3 on the header main body 1; the steam-water mixture can enter the header main body 1 through the second water cooling wall pipe 7; the steam-water mixture can also enter the header auxiliary body 2 through the expansion elbow pipe 6 and then through the first water cooling wall pipe 5, and the pipe body of the expansion elbow pipe 6 is bent to provide elastic compensation in the axial and transverse directions, and can absorb the linear expansion amount in the header auxiliary body 2 due to temperature changes; the header auxiliary body 2 is provided with a through hole, the first water cooling wall pipe 5 is welded on the header auxiliary body 2 and communicates with the through hole, the annular groove 8 on the header auxiliary body 2 is concentrically arranged with the through hole and located at the outer circle of the welding area, the annular groove 8 provides a certain deformation allowance for the welding area, and the expansion and contraction will not directly act on the welding point, and at the same time, when the welding area is subjected to thermal stress, the stress can be dispersed along the circumferential direction of the annular groove instead of being concentrated on the welding point itself; meanwhile, the first water cooling wall pipe 5 and the through hole are respectively provided with inner and outer chamfers, and the inner and outer chamfers are matched to disperse the stress to a larger area, reduce the accumulation of stress in a local position, and thus reduce the stress concentration coefficient; the steam-water mixture enters the header main body 1 and the header auxiliary body 2, and since the conventional long header is arranged in a split type, the concentrated stress generated due to the difference in thermal expansion at both ends can be reduced; the header main body 1 and the header auxiliary body 2 will expand in all directions during operation, and the expansion and contraction mechanism can stretch and contract like a spring through the cooperation of the bellows 41 and the sliding rod 44, and the elasticity and stretchability of the expansion and contraction mechanism can absorb and compensate the thermal expansion displacement between the header main body 1 and the header auxiliary body 2.
[0043] By arranging the axial and transverse elastic compensation of the expansion elbow pipe 6, the linear expansion amount in the header auxiliary body 2 due to temperature changes can be reduced; by arranging the annular groove 8 outside the welding area of the first water cooling wall pipe 5 and the header auxiliary body 2, a certain deformation allowance is provided, and the stress can be dispersed along the circumferential direction of the annular groove; the outer chamfer of the first water cooling wall pipe 5 is matched with the inner chamfer of the through hole of the header auxiliary body 2 to reduce the accumulation of stress in a local position; the split type header main body 1 and the header auxiliary body 2 are connected through the expansion and contraction mechanism, the concentrated stress generated due to the difference in thermal expansion at both ends can be reduced, and the thermal expansion displacement between the header main body 1 and the header auxiliary body 2 can be absorbed and compensated.
[0044] In the description of the utility model, need understanding is, the term "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and so on indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawing, just for the convenience of describing the utility model, and it is not indicated or implied that the indicated device or element must have a particular orientation, a particular orientation and operation, so it can not be understood as a limitation on the utility model.
[0045] The above-described embodiments are merely preferred modes of the utility model, and do not limit the scope of the utility model, and various modifications and improvements to the technical solutions of the utility model made by those skilled in the art without departing from the design spirit of the utility model shall fall within the protection scope of the utility model claimed.
Claims
1. A header structure for preventing cracks in header pipe seats, characterized in that, The utility model relates to a kind of water wall pipe connecting structure of boiler, including: Header main body (1), two ends of the header main body (1) are provided with header vice body (2) respectively, and the header vice body (2) is communicated with the header main body (1) by telescopic mechanism; Second water cooling wall pipe (7) is communicated on the header main body (1), and first water cooling wall pipe (5) is communicated on the header vice body (2), and outlet structure is communicated on the header main body (1).
2. The header structure according to claim 1, wherein: The telescopic mechanism includes bellows (41), and the both ends of the bellows (41) are fixedly connected with first flange (42) respectively, and sliding member is slidably connected between two first flanges (42).
3. The header structure according to claim 2, wherein: The sliding member includes a plurality of slide rods (44), and the plurality of slide rods (44) are coaxially arranged with the bellows (41), and the plurality of slide rods (44) are circumferentially equidistantly arranged, and the end of the slide rod (44) penetrates the first flange (42) and is fixedly connected with limiting piece.
4. The header structure according to claim 2, wherein: Second flange (43) is fixedly connected on the header main body (1) and the header vice body (2), and the second flange (43) is fixedly connected with the first flange (42).
5. The header structure according to claim 1, wherein: The first water cooling wall pipe (5) is communicated with the header vice body (2) by through hole, and the through hole is formed on the header vice body (2).
6. The header structure according to claim 5, wherein: Annular groove (8) is coaxially arranged at the outer edge of the through hole, and the annular groove (8) is formed on the header vice body (2).
7. The header structure according to claim 5, wherein: One end of the through hole is provided with inner chamfer, and the inner chamfer is located on the outer side wall of the header vice body (2), and one end of the first water cooling wall pipe (5) is provided with outer chamfer, and the inner chamfer is matched with the outer chamfer.
8. The header structure according to claim 1, wherein: Expansion compensation part is arranged on the first water cooling wall pipe (5).
9. The header structure according to claim 8, wherein: The expansion compensation part includes expansion elbow (6), and the water outlet end of the expansion elbow (6) is communicated on the first water cooling wall pipe (5).
10. The header structure for preventing cracks in the pipe seat of the header according to claim 1, wherein: The outlet structure includes outlet connecting pipe (3), one end of the outlet connecting pipe (3) is communicated with the header main body (1), and the other end of the outlet connecting pipe (3) is connected with steam-water separator.