Lower small header drain pipe joint structure for secondary superheater of garbage waste heat boiler

Abstract

The utility model discloses a drain pipe joint structure for a lower small header of a secondary superheater of a garbage waste heat boiler, and relates to the technical field of secondary superheaters of waste heat boilers. The secondary superheater lower small header solves the problems of inner wall abrasion and pipe explosion of an existing secondary superheater lower small header of a garbage waste heat boiler. A whistle pipe which is integrally formed and coaxially arranged is arranged on the inner side, close to a lower small header of a second-stage superheater, of a drain pipe joint body, a round end plate which is coaxially arranged is arranged at the end of the whistle pipe, and an inserting hole is formed in the side face of the lower small header of the second-stage superheater in the radial direction. The drain pipe joint body and the integrally-formed whistle pipe are inserted into the pipe joint insertion hole from outside to inside, the end of the whistle pipe extends into the second-stage superheater lower small header, and a plurality of water injection nozzles are formed in the side face of the whistle pipe and located on the inner side of the second-stage superheater lower small header. The multiple water injection nozzles are arranged in the axis direction of the second-stage superheater lower small header. The header is used for preventing the inner wall of the header from being scoured to cause pipe explosion.

Description

TECHNICAL FIELD

[0001] The utility model relates to waste heat boiler secondary superheater technical field, concretely relates to a kind of for waste heat boiler secondary superheater lower header drain pipe joint structure. BACKGROUND

[0002] Superheater is a kind of equipment, its function is to the saturated steam generated in the drum is heated again, thereby converting into superheated steam.Saturated steam, also known as wet steam, will be converted into dry steam after the heating of superheater.Superheater is mainly composed of inlet and outlet headers, numerous tube panels and drain system.According to its function and structure, superheater can be divided into primary, secondary and tertiary superheaters.In order to prevent the outlet temperature of steam from being too high, a primary water spray desuperheater is usually installed between primary and secondary superheaters, and a secondary water spray desuperheater is installed between secondary and tertiary superheaters.

[0003] As shown in Figure 1 , due to the uniqueness of superheater structure, we observed that the pressure of secondary superheater inlet header 1 is usually higher than that of secondary superheater outlet header 2 in the actual operation of boiler.When the primary water spray desuperheater sprays to the secondary superheater inlet header 1, the generated steam condensate will flow into the drain main 5 along the drain pipe I 3.If the valve of drain main 5 is in closed state, it is equivalent to short-circuiting the entire secondary superheater.In Figure 1 , the pressure of drain pipe II 4 on the outlet side is relatively low, therefore the steam condensate in drain main 5 will flow back to drain pipe II 4 and spray onto the upper inner wall of secondary superheater lower header 6 and the drain pipe joint 7 near it.This phenomenon will cause the upper inner wall of secondary superheater lower header 6 and the adjacent drain pipe joint 7 to be eroded by steam condensate, which may cause thermal fatigue after long-term operation, and further lead to pipe wall thinning or even pipe burst.The greater the water spray amount of water spray desuperheater, the more serious the erosion and pipe burst risk of the upper inner wall of secondary superheater lower header 6 and the adjacent drain pipe joint 7.

[0004] The existing secondary superheater lower header drain pipe joint structure is shown in Figure 2 , on the one hand, in the traditional design, the drain pipe joint 7 and the secondary superheater lower header 6 adopt full-penetration welding connection mode.On the other hand, during the operation of boiler, the drain pipe joint 7 will appear back-spraying phenomenon.Due to the small inner diameter of drain pipe joint 7 (the inner diameter of drain pipe joint 7 is 18mm), the resistance is large, and the steam condensate will be shot into the secondary superheater lower header 6 like a bullet, which not only will cause the inner wall of secondary superheater lower header 6 to be damaged or even burst, but also will cause the abrasion of the surrounding pipe wall, thereby causing safety problems during the operation of boiler.These problems may bring immeasurable loss to production. SUMMARY

[0005] The utility model discloses a kind of drain pipe joints for waste heat boiler secondary superheater lower small header, which comprises a drain pipe joint body 701, and a whistle pipe 702 integrally formed and coaxially arranged is provided on the inner side of the secondary superheater lower small header 6.

[0006] The technical scheme of the utility model is:

[0007] The utility model discloses a kind of drain pipe joints for waste heat boiler secondary superheater lower small header, which comprises a drain pipe joint body 701, and a whistle pipe 702 integrally formed and coaxially arranged is provided on the inner side of the secondary superheater lower small header 6, the whistle pipe 702 is circular tubular structure, the circular end plate 703 coaxially arranged is equipped in whistle pipe (702) end, whistle pipe (702) is inserted into secondary superheater lower small header (6) pipe joint insertion hole from outside to inside in secondary superheater lower small header (6) inner side along small header axial direction and is opened with insertion hole, whistle pipe 702 side is equipped with multiple water jet ports 704, and the multiple water jet ports 704 are located in secondary superheater lower small header 6 inner side.

[0008] Further, the multiple water jet ports 704 are arranged along the axis M-M direction of the secondary superheater lower small header 6.

[0009] Further, the number of water jet ports 704 is eight, and the eight water jet ports 704 are respectively located on both sides of the whistle pipe 702.

[0010] Further, the water jet port 704 is a circular through hole, and the inner diameter of the water jet port 704 is 8mm.

[0011] Further, the center distance between the two water jet ports 704 adjacent inside and outside is 11m.

[0012] Further, the inner diameter of the whistle pipe 702 is 18mm, and the whistle pipe 702 inner hole and the circular end plate 703 are gap fitted, and the circular end plate 703 and the whistle pipe 702 are connected by welding.

[0013] Further, the outer diameter of the whistle pipe 702 is 24mm, and the pipe joint insertion hole on the secondary superheater lower small header 6 and the whistle pipe 702 are gap fitted.

[0014] Further, the drain pipe joint body 701 comprises a first pipe segment, a second pipe segment and a third pipe segment integrally formed and coaxially arranged from top to bottom, the first pipe segment and the third pipe segment are both cylindrical pipe segments, the outer diameter of the first pipe segment is 36mm, the outer diameter of the third pipe segment is 28mm, and the second pipe segment is a conical pipe segment.

[0015] Further, the first pipe section of the hydrophobic pipe joint body 701 is connected with the secondary superheater lower header 6 by welding.

[0016] Further, the whistle pipe 702 is a 15CrMoG high-pressure alloy pipe.

[0017] The utility model discloses the following effects compared with prior art:

[0018] 1. The whistle pipe is inserted into the pipe joint socket of the secondary superheater lower header, which significantly prolongs the service life of the secondary superheater lower header. The utility model not only prolongs the service life of the equipment, but also simplifies the maintenance process. By reducing the frequent replacement due to the damage of the secondary superheater lower header, the maintenance cost and downtime are reduced, thereby improving the operation efficiency and reliability of the entire system.

[0019] 2. The utility model optimizes the hydrophobic structure of the secondary superheater, effectively reduces the cost under the premise of ensuring performance, and solves the problem of pipe explosion that has plagued waste power plants for many years. Through the carefully designed hydrophobic structure, the operation efficiency of the secondary superheater is significantly improved, and the heat energy loss caused by poor drainage is reduced. In addition, the optimized structure also has better corrosion resistance, further prolongs the service life of the equipment, and reduces the additional cost caused by frequent maintenance or replacement of parts. These improvements not only improve the economic benefit of the waste power plant, but also enhance the stability and safety of the entire power generation system.

[0020] 3. The utility model improves the reliability of the boiler by implementing reliable technical measures. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a structure schematic view of the secondary superheater system;

[0022] Figure 2 is a side view of the existing secondary superheater lower header hydrophobic pipe joint structure;

[0023] Figure 3 is a side view of the secondary superheater lower header hydrophobic pipe joint structure for the waste heat boiler of the utility model.

[0024] In the figure: 1, secondary superheater inlet header; 2, secondary superheater outlet header; 3, hydrophobic pipe I; 4, hydrophobic pipe II; 5, hydrophobic main pipe; 6, secondary superheater lower header; 7, hydrophobic pipe joint; 701, hydrophobic pipe joint body; 702, whistle pipe; 703, round end plate; 704, water injection port. DETAILED DESCRIPTION

[0025] Specific implementation one: combined with Figure 3The embodiment is illustrated, and the embodiment is a structure of a drain pipe joint of a lower header of a secondary superheater of a waste heat boiler, which comprises a drain pipe joint body 701, and a whistle pipe 702 is integrally formed and coaxially arranged on the inner side of the lower header 6 of the secondary superheater close to the drain pipe joint body 701, the whistle pipe 702 is a circular tubular structure, a circular end plate 703 is coaxially arranged on the end of the whistle pipe 702, and a plug hole is formed in the inner side of the lower header 6 of the secondary superheater along the axial direction of the header, the drain pipe joint body 701 and the integrally formed whistle pipe 702 are inserted into the pipe joint plug hole of the lower header 6 of the secondary superheater from the outside to the inside, a plurality of water injection ports 704 are formed on the side of the whistle pipe 702, and the plurality of water injection ports 704 are located on the inner side of the lower header 6 of the secondary superheater.

[0026] The whistle pipe joint is arranged on the inner wall of the lower header of the secondary superheater, thereby effectively prolonging the service life of the header and reducing the maintenance cost.

[0027] The whistle pipe joint of the utility model is designed uniquely, the shape structure of the drain pipe joint is optimized, the service life of the equipment is effectively prolonged, and the operation safety of the system is improved.

[0028] Specific implementation method two: in combination with Figure 3 The embodiment is illustrated, and the plurality of water injection ports 704 of the embodiment are arranged along the axis M-M direction of the lower header 6 of the secondary superheater.

[0029] Specific implementation method three: in combination with Figure 3 The embodiment is illustrated, and the number of the water injection ports 704 of the embodiment is eight, the eight water injection ports 704 are respectively located on the two sides of the whistle pipe 702, and the four water injection ports 704 on each side of the whistle pipe 702 are sequentially and uniformly arranged from the outside to the inside along the length direction of the whistle pipe 702.

[0030] Specific implementation four: combination Figure 3 In this embodiment, the water injection port 704 is a circular hole, and the inner diameter of the water injection port 704 is 8 mm. In this way, eight water injection ports with a diameter of 8 mm are arranged along the axis direction of the whistle pipe of the lower header of the secondary superheater. When the drain valve is opened, these water injection ports help to drain; when the drain valve is closed, these water injection ports can prevent steam condensate from washing and corroding the inner wall of the header, which effectively solves the problem of wear of the lower header of the secondary superheater. The other components and connection relationships are the same as those of embodiment one, two or three.

[0031] Specific implementation five: combination Figure 3 In this embodiment, the center distance between the two water injection ports 704 adjacent inside and outside is 11 m. The other components and connection relationships are the same as those of embodiment one, two, three or four.

[0032] Specific implementation six: combination Figure 3 In this embodiment, the whistle pipe 702 has an inner diameter of 18 mm, the whistle pipe 702 is in clearance fit with the circular end plate 703, and the circular end plate 703 is connected with the whistle pipe 702 by welding. The other components and connection relationships are the same as those of embodiment one, two, three, four or five.

[0033] Specific implementation seven: combination Figure 3 In this embodiment, the whistle pipe 702 has an outer diameter of 24 mm, and the pipe joint socket on the lower header 6 of the secondary superheater is in clearance fit. The other components and connection relationships are the same as those of embodiment one, two, three, four, five or six.

[0034] Specific implementation eight: combination Figure 3 In this embodiment, the drain pipe joint body 701 includes a first pipe segment, a second pipe segment and a third pipe segment which are integrally formed and coaxially arranged from top to bottom, the first pipe segment and the third pipe segment are both cylindrical pipe segments, the outer diameter of the first pipe segment is 36 mm, the outer diameter of the third pipe segment is 28 mm, and the second pipe segment is a conical pipe segment. The other components and connection relationships are the same as those of embodiment one, two, three, four, five, six or seven.

[0035] Specific implementation nine: combination Figure 3In this embodiment, the first pipe section of the hydrophobic pipe joint body 701 is connected to the lower small header 6 of the secondary superheater by welding. In this way, the whistle pipe 702 of the hydrophobic pipe joint 7 is inserted into the interior of the lower small header 6 of the secondary superheater, and the hydrophobic pipe joint body 701 of the hydrophobic pipe joint 7 is in full penetration structure with the lower small header 6 of the secondary superheater. This technology has been applied to many modified boilers, and the anti-wear effect is very significant. The other components and connection relationships are the same as those of embodiments one, two, three, four, five, six, seven, or eight.

[0036] Embodiment ten: Figure 3 In this embodiment, the whistle pipe 702 is a 15CrMoG high-pressure alloy pipe. In this way, the hydrophobic pipe joint 7 has good heat conduction performance, can effectively reduce thermal stress, and prolong the service life of the equipment. In actual application, this structure design not only improves the stability of the system, but also reduces the maintenance cost. The other components and connection relationships are the same as those of embodiments one, two, three, four, five, six, seven, eight, or nine.

[0037] The above embodiments are only used to illustrate the technical solutions of the present application, but not to limit it. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to some technical features. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A structure of a drain pipe joint for a lower header of a secondary superheater of a waste heat boiler, comprising a drain pipe joint body (701), characterized in that: The hydrophobic pipe joint body (701) is provided with an integrally formed and coaxially arranged whistle pipe (702) on the inner side of the secondary superheater lower header (6), the whistle pipe (702) is a circular tubular structure, the end of the whistle pipe (702) is provided with a coaxially arranged circular end plate (703), the whistle pipe (702) is provided with a insertion hole on the inner side of the secondary superheater lower header (6) along the axis of the header, the hydrophobic pipe joint body (701) and the integrally formed whistle pipe (702) are inserted into the pipe joint insertion hole of the secondary superheater lower header (6) from the outside to the inside, and the end of the whistle pipe (702) extends to the inside of the secondary superheater lower header (6), a plurality of water injection ports (704) are arranged on the side of the whistle pipe (702), and the plurality of water injection ports (704) are located on the inner side of the secondary superheater lower header (6).

2. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 1, characterized in that: The plurality of water injection ports (704) are arranged along the axis (M-M) direction of the secondary superheater lower header (6).

3. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 2, characterized in that: The number of the water injection ports (704) is eight, and the eight water injection ports (704) are respectively located on both sides of the whistle pipe (702), and the four water injection ports (704) on each side of the whistle pipe (702) are arranged in sequence from the outside to the inside along the length direction of the whistle pipe (702).

4. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 3, characterized in that: The water injection port (704) is a circular through hole, and the inner diameter of the water injection port (704) is 8mm.

5. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 4, characterized in that: The center distance between the two adjacent water injection ports (704) is 11m.

6. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 5, characterized in that: The inner diameter of the whistle pipe (702) is 18mm, the whistle pipe (702) inner hole and the circular end plate (703) are gap fitted, and the circular end plate (703) and the whistle pipe (702) are connected by welding.

7. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 6, characterized in that: The outer diameter of the whistle pipe (702) is 24mm, and the pipe joint insertion hole on the secondary superheater lower header (6) is gap fitted.

8. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 7, characterized in that: The hydrophobic pipe joint body (701) comprises a first pipe segment, a second pipe segment and a third pipe segment which are integrally formed and coaxially arranged from top to bottom, the first pipe segment and the third pipe segment are both cylindrical pipe segments, the outer diameter of the first pipe segment is 36mm, the outer diameter of the third pipe segment is 28mm, and the second pipe segment is a conical pipe segment.

9. The structure of the drain pipe joint of the lower collecting header of the secondary superheater of the waste heat boiler according to claim 8, characterized in that: The first pipe segment of the hydrophobic pipe joint body (701) and the secondary superheater lower header (6) are connected by welding.

10. A structure of a drain pipe joint of a lower collecting header of a secondary superheater of a waste heat boiler according to claim 1, 3, 6 or 7, characterized in that: The whistle pipe (702) is a 15CrMoG high-pressure alloy pipe.

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