Membrane type water cooling wall comprising bent flat steel and used for boiler

Abstract

The utility model provides a boiler membrane type water cooling wall containing bent flat steel, which is characterized in that the boiler membrane type water cooling wall is formed by alternately welding the bent flat steel and steel pipes, the bent flat steel comprises a left wing and a right wing, an included angle is arranged between the left wing and the right wing, and the left wing and the right wing have elasticity due to the included angle. When the bent flat steel is heated to expand, the left wing and the right wing are stretched towards the two sides, the angle of the included angle is increased, and then stretching stress generated during expansion is absorbed; when the bent flat steel is cooled and contracted, the left wing and the right wing are extruded towards the inner side, the angle of the included angle is reduced, then extrusion stress generated during contraction is absorbed, and the left wing and the right wing are integrally formed. Elastic compensation is added to existing plane flat steel, the problem that a boiler is damaged due to deformation of the membrane type water cooling wall is solved to a certain degree, the absorption area is increased, and the heat rate is increased.

Description

A membrane water-cooled wall for boilers comprising bent flat steel Technical Fields

[0001] This utility model relates to the field of boiler heat transfer technology, specifically to a membrane water-cooled wall for boilers comprising bent flat steel. Background Technology:

[0002] Membrane water-cooled walls are evaporative heating surfaces arranged around the boiler. The heat transfer coefficient of membrane water-cooled walls is generally between 95 and 160 W / (m2.℃). They mainly absorb the radiant heat from the high-temperature flames and flue gas in the furnace, and can quickly transfer heat to the working medium, improving the boiler's thermal efficiency. At the same time, they protect the structure of the furnace wall. It is one of the core components of modern boilers and is widely used in power plant boilers, industrial boilers, and waste heat boilers.

[0003] Objective drawbacks of existing technologies:

[0004] 1. The boiler membrane water-cooled wall is made by welding flat steel between steel pipes to form a continuous heating surface. During the welding process, the weld is long and the local heating welding stress is too high, which may also cause the membrane water-cooled wall to deform, affecting the accuracy and resulting in large errors during the later boiler installation.

[0005] 2. Due to the influence of the furnace structure, if the spacing between the fins of the membrane water-cooled wall is too large, the heat transfer effect will be reduced, the fins will overheat, and the water-cooled wall tubes will be torn.

[0006] 3. During normal operation of the boiler, the temperature inside the boiler furnace reaches 800℃~1200℃. The membrane water-cooled wall expands due to heat. When the boiler stops operating, the furnace temperature drops, and the membrane water-cooled wall contracts due to cold. Frequent thermal expansion and contraction may cause the weld between the steel pipe and the flat steel to tear, resulting in water leakage from the steel pipe or air and smoke leakage from the furnace. Invention content:

[0007] To address the problems of easy deformation during welding of existing boiler membrane water-cooled walls, excessively wide flat steel bars, and weld tearing caused by expansion and contraction stress between steel pipes and flat steel bars during normal operation, ultimately damaging the boiler, this utility model provides a boiler membrane water-cooled wall comprising bent flat steel bars. Its features include: alternating welding of bent flat steel bars and steel pipes; the bent flat steel bars include a left wing and a right wing; an angle is provided between the left wing and the right wing; this angle provides elasticity between the left wing and the right wing.

[0008] When the bent flat steel expands due to heat, the left and right wings are stretched to both sides, and the included angle increases, thereby absorbing the tensile stress during expansion.

[0009] When the bent flat steel is cooled and shrinks, the left and right wings are squeezed inward, and the included angle becomes smaller, thereby absorbing the compressive stress during shrinkage.

[0010] The left wing and the right wing are integrally formed.

[0011] At room temperature, the included angle is 60°-150°.

[0012] When it is necessary to widen the distance between two adjacent steel pipes, a left flat steel bar is welded to the left side of the left wing, and a right flat steel bar is welded to the right side of the right wing. Both the left flat steel bar and the right flat steel bar are welded to the adjacent steel pipes.

[0013] The two ends of the bent flat steel are welded to the center of the side of the steel pipe.

[0014] The left and right flat steel bars are both welded to the center of the adjacent sides of the steel pipe.

[0015] The advantages of this utility model are as follows:

[0016] 1. This type of membrane water-cooled wall structure is relatively simple and will not increase the economic burden too much;

[0017] 2. The addition of elastic compensation has solved the problem of boiler damage caused by deformation of the membrane water-cooled wall to a certain extent;

[0018] 3. Membrane water-cooled walls increase the absorption area and improve the heat efficiency;

[0019] 4. It facilitates the reduction of furnace wall weight and significantly improves the sealing of local areas such as furnace doors. Figure description:

[0020] Figure 1 is a schematic diagram of the structure of this utility model;

[0021] Figure 2 is a schematic diagram of the structure of the present invention after the steel pipe spacing is widened.

[0022] Attached image labels:

[0023] 1. Bending flat steel 2. Steel pipe 11. Left wing 12. Right wing 13. Angle

[0024] 14. Left-side flat steel bar 15. Right-side flat steel bar Detailed implementation method:

[0025] As shown in the figure, this utility model provides a membrane water-cooled wall for boilers containing bent flat steel, characterized in that: it is composed of bent flat steel 1 and steel pipe 2 welded alternately, the bent flat steel 1 includes a left wing 11 and a right wing 12, and an included angle 13 is provided between the left wing 11 and the right wing 12, the included angle 13 makes the left wing 11 and the right wing 12 elastic.

[0026] When the bent flat steel 1 is heated and expands, the left wing 11 and the right wing 12 are stretched to both sides, and the included angle 13 becomes larger, thereby absorbing the tensile stress during expansion.

[0027] When the bent flat steel 1 is cooled and shrinks, the left wing 11 and the right wing 12 are squeezed inward, and the included angle 13 becomes smaller, thereby absorbing the compressive stress during shrinkage.

[0028] The left wing 11 and the right wing 12 are integrally formed.

[0029] At room temperature, the included angle 13 is 60°-150°.

[0030] When it is necessary to widen the distance between two adjacent steel pipes 2, a left flat steel bar 14 is welded to the left side of the left wing 11, and a right flat steel bar 15 is welded to the right side of the right wing 12. The left flat steel bar 14 and the right flat steel bar 15 are both welded to the adjacent steel pipes 2.

[0031] The two ends of the bent flat steel 1 are welded to the center position of the side of the steel pipe 2.

[0032] The left flat steel 14 and the right flat steel 15 are both welded to the center of the adjacent sides of the steel pipe 2.

[0033] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A membrane water-cooled wall for boilers comprising bent flat steel, characterized in that: It is composed of alternating welded bent flat steel (1) and steel pipe (2). The bent flat steel (1) includes a left wing (11) and a right wing (12). An included angle (13) is provided between the left wing (11) and the right wing (12). The included angle (13) makes the left wing (11) and the right wing (12) elastic. When the bent flat steel (1) is heated and expands, the left wing (11) and the right wing (12) are stretched to both sides, and the angle (13) becomes larger, thereby absorbing the tensile stress during expansion. When the bent flat steel (1) is cooled and contracts, the left wing (11) and the right wing (12) are squeezed inward, and the angle (13) becomes smaller, thereby absorbing the compressive stress during contraction. The left wing (11) and the right wing (12) are integrally formed.

2. The boiler membrane water-cooled wall comprising bent flat steel according to claim 1, characterized in that: At room temperature, the included angle (13) is 60°-150°.

3. The boiler membrane water-cooled wall comprising bent flat steel according to claim 1, characterized in that: When it is necessary to widen the distance between two adjacent steel pipes (2), a left flat steel bar (14) is welded to the left side of the left wing (11), and a right flat steel bar (15) is welded to the right side of the right wing (12). The left flat steel bar (14) and the right flat steel bar (15) are both welded to the adjacent steel pipes (2).

4. The membrane water-cooled wall for boilers comprising bent flat steel according to claim 1, characterized in that: The two ends of the bent flat steel (1) are welded to the center of the side of the steel pipe (2).

5. The boiler membrane water-cooled wall comprising bent flat steel according to claim 3, characterized in that: The left flat steel (14) and the right flat steel (15) are both welded to the center of the adjacent sides of the steel pipe (2).

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