CN219624018U

CN219624018U - Boiler overheat screen system structure

Info

Publication number: CN219624018U
Application number: CN202320332218.1U
Authority: CN
Inventors: 胡志洁
Original assignee: Wuxi Huaguang Environment and Energy Group Co Ltd
Current assignee: Wuxi Huaguang Environment and Energy Group Co Ltd
Priority date: 2023-02-28
Filing date: 2023-02-28
Publication date: 2023-09-01
Anticipated expiration: 2033-02-28

Abstract

The utility model relates to the technical field of tube panels, in particular to a boiler overheat panel system structure which can effectively solve the problem of deformation of a screen-passing type superheater and ensure the normal operation of a power plant.

Description

Boiler overheat screen system structure

Technical Field

The utility model relates to the technical field of tube panels, in particular to a boiler overheat panel system structure.

Background

The deformation of the circulating fluidized bed screen-passing superheater (superheater screen) is a long-standing problem which directly affects the long-term stable operation of the boiler. The conventional superheated screen system is designed as shown in fig. 1, after steam enters the superheated screen inlet header 1, enters the superheater outlet header 3 through the superheated screen 2, then enters the superheated screen outlet header 6 through the superheated screen connecting pipeline 5, and finally enters the main steam pipeline 7 through the main pipe, wherein the metal expansion joint 4 is designed at the position of the screen outlet and the water-cooled wall through pipe. Because the boiler combustion temperature is higher, in long-time high temperature operation process, the overheated screen can expand the restriction often, and the influence of factors such as in-screen steam flow drift makes overheated screen produce different degree crooked and distortion, and more serious the case can lead to overheated screen tube explosion blowing out, directly influences the normal operating of power plant.

Disclosure of Invention

The utility model provides a boiler overheat screen system structure which can effectively solve the problem of deformation of a screen-passing type superheater and ensure normal operation of a power plant.

The technical scheme is as follows: the utility model provides a boiler heat screen system structure, its includes water-cooling wall and heat screen, the upper and lower both ends of heat screen all pass the water-cooling wall and connect heat screen outlet header and overheated screen import header respectively, its characterized in that, the upper end of overheated screen with the pipe department of passing of water-cooling wall is provided with nonmetal expansion joint, every overheated screen outlet header passes through the outlet pipe connection main steam pipeline of independent area elbow.

The device is further characterized in that the opening size of the header pipe joint at the lower part of the overheat screen inlet header is smaller than that of the other header pipe joints;

two sides of the pipe penetrating position of the overheat screen and the water-cooled wall are respectively provided with two letting pipes, and the pipe penetrating position is provided with an aluminum silicate fiber board for sealing;

the inner diameter of the outlet pipeline is smaller than that of the overheat screen outlet header;

the outlet duct is constituted by a horizontal L-shaped tube and a vertical L-shaped tube.

After the utility model is adopted, the non-metal expansion joint is arranged at the positions of the overheat screen and the through pipe of the water cooling wall, the free expansion of the overheat screen is not inhibited, the outlet header of the overheat screen is connected with the main steam pipeline through the independent outlet pipeline, the collecting header is not arranged, the size of the connecting pipe is reduced, the length of the connecting pipe is increased, the expansion amount can be absorbed through the elbow and the deflection of the outlet pipeline when the overheat screen expands upwards, the problem of deformation of the overheat screen is effectively solved, and the normal operation of a power plant is ensured.

Drawings

FIG. 1 is a schematic diagram of a prior art structure;

FIG. 2 is a schematic diagram of the structure of the present utility model;

FIG. 3 is a schematic view of the direction A in FIG. 2;

FIG. 4 is a schematic diagram of the outlet header of the overheat screen;

FIG. 5 is a schematic view of a tube passing through the upper end of the heat shield and the water wall;

FIG. 6 is a schematic diagram of the sealing between the upper end of the heat shield and the water wall pipe.

Detailed Description

As shown in fig. 2 to 6, a boiler overheat screen system structure comprises a water-cooling wall 8 and an overheat screen 2, wherein the upper end and the lower end of the overheat screen 2 pass through the water-cooling wall 8 and are respectively connected with an overheat screen outlet header 3 and an overheat screen inlet header 1, a nonmetal expansion joint 11 is arranged at the positions of the upper end of the overheat screen 2 and a through pipe of the water-cooling wall 8, and each overheat screen outlet header 3 is connected with a main steam pipeline 7 through an independent outlet pipeline 10 with an elbow. The conventional boiler design is that the outlet of the overheat screen adopts metal expansion joints, but the expansion stress of the metal expansion joints is large, the metal expansion joints are similar to springs, the larger the expansion amount is, the larger the recovery force of the metal expansion joints is, the expansion of the overheat screen can be blocked in the upward expansion process of the overheat screen, and the overheat screen is deformed, so that the non-metal expansion joints 11 are adopted, have no expansion stress, do not inhibit the free expansion of the overheat screen 2, and can solve the deformation problem of the overheat screen 2.

The size of the opening of the header pipe joint at the lower part of the inlet header 1 of the overheat screen is smaller than that of the other header pipe joints, namely the size of the opening of the header pipe joint at the part of the slope line is phi 24 in the drawing, and the other is phi 30, and by adopting a throttling measure, the flow area is reduced, the resistance is increased, the flow is reduced, the flow of each pipe in the whole overheat screen is just more uniform, the flow of the pipe of the overheat screen close to the center side of the hearth is not larger than that of the pipes at other parts, and the problem of overheat screen deformation caused by large temperature deviation due to the steam flow is solved.

In conventional boiler design, overheated screen poling department, the water-cooling wall lets the pipe let two pipes only, but in the installation, thereby can lead to overheated screen and water-cooling wall to be close to influence overheated screen inflation, lead to the screen to warp, and conventional design screen is crossed poling department and is adopted the castable to seal simultaneously, beats screen and water-cooling wall with the castable to die easily when beating the castable, influences the screen to cross the inflation, leads to the screen to cross the deformation. In the utility model, two yielding pipes are respectively arranged at two sides of the pipe penetrating positions of the overheat screen 2 and the water-cooled wall 8, so that four pipes are realized, the pipe penetrating space is enlarged, and the sealing aluminum silicate fiber board 9 is arranged at the pipe penetrating position, so that the screen overstretching is not influenced, and the problem of the screen overstretching is solved.

In conventional boiler designs, each superheating screen outlet header passes through a connecting pipe and then enters the superheating screen outlet header, and then enters a main steam pipeline through a main pipe. The arrangement mode is large in rigidity due to the fact that the overheat screen outlet collecting box is large in actual operation, expansion of the overheat screen outlet collecting box is blocked when the screen outlet collecting box expands upwards, so that screen bending is caused, and meanwhile, the main steam main pipe has a reverse thrust to the screen outlet collecting box, so that the overheat screen is bent. Therefore, in the utility model, the inner diameter of the outlet pipeline 5 is smaller than that of the overheat screen outlet header 3, the outlet pipeline 10 is formed by a horizontal L-shaped pipe and a vertical L-shaped pipe, a collecting header is not arranged, and steam from each screen directly enters the main steam pipeline through a necking to a small pipeline.

According to the utility model, by adopting the measures of shielding through inlet header throttling, arranging an independent flexible nonmetal expansion joint at the outlet of the overheating shielding, enlarging the fit clearance between the shielding through outlet and the furnace top water-cooled wall, shielding through outlet pipeline L-shaped arrangement and the like, through practical engineering verification, the structure can well solve the deformation problem of the fluidized bed boiler shielding type superheater.

Claims

1. The utility model provides a boiler heat screen system structure, its includes water-cooling wall and heat screen, the upper and lower both ends of heat screen all pass the water-cooling wall and connect heat screen outlet header and overheated screen import header respectively, its characterized in that, the upper end of overheated screen with the pipe department of passing of water-cooling wall is provided with nonmetal expansion joint, every overheated screen outlet header passes through the outlet pipe connection main steam pipeline of independent area elbow.

2. A boiler superheat screen system structure as claimed in claim 1, wherein the header pipe fitting opening size in the lower portion of the superheat screen inlet header is smaller than the remaining header pipe fitting opening sizes.

3. The boiler overheat screen system structure of claim 1, wherein two passing pipes are respectively arranged on two sides of the overheat screen and the passing pipe of the water-cooled wall, and sealing aluminum silicate fiber boards are arranged on the passing pipe.

4. A boiler superheat screen system structure as claimed in claim 1, wherein the inner diameter of the outlet conduit is smaller than the inner diameter of the superheat screen outlet header.

5. A boiler heat shield system structure according to claim 1 wherein said outlet duct is comprised of a horizontal L-shaped tube and a vertical L-shaped tube.