WO2020062726A1

WO2020062726A1 - Membrane type water-cooled wall having anti-abrasion heated surface and preparation method therefor

Info

Publication number: WO2020062726A1
Application number: PCT/CN2019/071988
Authority: WO
Inventors: 曲作鹏; 陈威; 叶怀宇; 欧阳晓平; 刘宗德; 董长青; 陈大智; 李晓娅; 唐红雨
Original assignee: 华北电力大学; 江苏科环新材料有限公司
Priority date: 2018-09-29
Filing date: 2019-01-16
Publication date: 2020-04-02

Abstract

A membrane type water-cooled wall having an anti-abrasion heated surface and a preparation method therefor. According to the preparation method, an anti-abrasion tile (4) is fixed to a heated surface of a water-cooled wall pipe by clamping a silicon carbide particle reinforced adhesive between a heated surface of a fin tube (1) that forms the membrane type water-cooled wall and the anti-abrasion tile (4), thus forming an anti-abrasion layer, and preparing a membrane type water-cooled wall having an anti-abrasion heated surface; the fin tube (1) and the anti-abrasion tile (4) are tightly combined without a gap, so that the heated surface of the membrane type water-cooled wall is resistant to corrosion and abrasions, high heat exchange efficiency is achieved, and the service life of the membrane type water cooling wall may be prolonged.

Description

Anti-abrasion film-type water-cooled wall of heating surface and preparation method thereof

This application claims the priority of Chinese patent application CN201811150408.1 entitled "A film-type water-cooled wall with anti-abrasion on heated surface and its preparation method" filed on September 29, 2018, and filed on September 29, 2018 The priority of the Chinese patent application CN201821604638.6, entitled "A tube for water-cooled walls with abrasion-resistant heating surface", is incorporated herein by reference in its entirety.

Technical field

The invention belongs to the technical field of thermal pipeline protection, and relates to a film-type water-cooled wall with anti-abrasion on a heating surface and a preparation method thereof.

Background technique

In the actual operation of the thermal company equipment, boiler convection through the heat pipe water-cooled wall pipe is widely used. In the process of use, the water-cooled wall pipe is directly exposed, which is easy to be washed by the pulverized coal particles and corrosive gas in the boiler. After scouring and erosion, water-cooled wall tubes have been subject to wear and corrosion to varying degrees. In severe cases, the tube bursts, which not only affects the operation of the equipment, but also cannot guarantee safety. Frequent replacement of the water-wall tubes is required to ensure the normal operation of the equipment. For the operator, replacing the water-cooled wall pipe has a small space for replacement. The equipment needs to be stopped during the replacement and it must be cooled before it can work. This not only affects the normal operation of the equipment, but also partially interrupts the heat supply of the entire city.

To solve this problem, various methods have been used. One method is to hang anti-wear tiles (also called anti-wear hoods), anti-wear plates, anti-wear protective covers, anti-wear cover plates, anti-corrosion cover plates, boiler climbing pipes, anti-wear pressure plates, etc. on the heating surface of boiler pipes. These components are common accessories for the heating surface tubes of utility boilers, and are usually used in conjunction with snap rings. Compared with other water-cooled wall tube anti-abrasion laser cladding, surfacing wear-resistant anti-corrosion and thermal spray wear-resistant anti-corrosion coating methods, the method has low cost, convenient operation, good anti-abrasion effect, and disadvantages are low heat transfer efficiency.

Therefore, the current problem is the need to research and develop a water-cooled wall tube that can effectively reduce the corrosion and wear of water-cooled wall tubes while maintaining high thermal efficiency, low cost, and easy operation. method.

Summary of the Invention

The technical problem to be solved by the present invention is to provide a film-type water-cooled wall with anti-abrasion on the heating surface and a method for preparing the same in view of the shortcomings of the prior art. In this method, a silicon carbide particle reinforced adhesive is sandwiched between a heating surface of a finned tube constituting a film-type water-cooled wall and an anti-wearing tile to fix the anti-wearing tile on the heating surface of the water-cooled wall pipe, thereby forming an anti-abrasion layer, thereby being prepared. The abrasion-resistant film-type water-cooled wall of the heating surface has a tight connection between the finned tube and the wear-resistant tile without gaps, which makes the heating surface of the film-type water-wall not only resistant to corrosion and abrasion, but also has high heat exchange efficiency, extending the film The service life of the water-cooled wall improves the economic efficiency of the enterprise.

To this end, the first aspect of the present invention provides a film-type water-cooled wall with anti-abrasion on the heating surface, which includes at least two fin tubes with anti-abrasion on the heating surface. The fin tubes are welded in a row by fins, wherein The anti-abrasion fin tube on the heating surface includes a fin tube and an anti-abrasion layer covering the heating surface of the fin tube. The anti-abrasion layer includes an interlayer covering the heating surface of the fin tube and covering the interlayer. The wear-resistant tile on the outer surface and the wear-resistant tile snap ring provided on the outer surface of the wear-resistant tile, the wear-resistant tile and the heating surface of the finned tube are bonded by a sandwich, and tightly joined by the wear-resistant tile snap ring.

In the present invention, the interlayer is composed of a steel mesh filled with silicon carbide particles to reinforce a high-temperature-resistant composite adhesive.

In some preferred embodiments of the present invention, the silicon carbide particle reinforced high-temperature-resistant composite adhesive is prepared by using silicon carbide particles and high-temperature-resistant adhesive in a weight ratio of 3: 1.

In some specific preferred embodiments of the present invention, it is preferred that the high-temperature-resistant adhesive includes 1280 ° C high-temperature-resistant sealant and / or Den Braven Sealants 1200 ° C (Dutch swallow high transparent sealant, high-temperature resistance 1200 ° C).

In some embodiments of the present invention, the expanded metal is welded to the fins on the heating surface of the finned tube.

In some embodiments of the present invention, the thickness of the expanded metal mesh is 1-5 mm.

In some embodiments of the present invention, the steel mesh is a stainless steel mesh that is resistant to high temperature abrasion.

In the present invention, there is no gap between the heating surface of the finned tube and the wear-resistant tile.

In some specific embodiments of the present invention, there are no gaps between the heating surface of the finned tube and the inner surface of the interlayer, between the outer surface of the interlayer and the inner surface of the wear-resistant tile, and within the interlayer.

In some embodiments of the present invention, ears are provided on one side of the wear-resistant tile, and the width of the ears is the same as the width of the fins of the fin tube. gap.

In the present invention, the radius of the inner surface of the wear-resistant tile is 1-5 mm larger than the radius of the outer surface of the finned tube.

In some embodiments of the present invention, the thickness of the anti-wear tile is 1-5 mm.

Preferably, the material of the anti-wear tile is a stainless steel plate resistant to high temperature abrasion.

In the present invention, the end of the wear-resistant slip ring is inserted into a notch on the wear-resistant slip ear, and is welded to the fin of the fin tube there.

In some embodiments of the present invention, the inner diameter of the anti-wear shoe ring is the same as the outer diameter of the anti-wear shoe, and the width is 30mm-50mm.

In other embodiments of the present invention, the thickness of the anti-wear slip ring is 3-5 mm.

Preferably, the material of the anti-wear Waco ring is a stainless steel plate resistant to high temperature abrasion.

A second aspect of the present invention provides a method for preparing a film-type water-cooled wall with abrasion resistance on a heated surface, which includes:

Step A, sandblasting and roughening the heating surface of the finned tube on the film-type water-cooled wall;

Step B: welding the steel mesh on the heating surface of the fin tube by welding on the fin of the fin tube;

Step C, filling a silicon carbide particle-reinforced high-temperature-resistant composite adhesive into a grid of a steel mesh welded on a heating surface of the finned tube;

Step D, buckle the wear-resistant tile on the steel mesh of the grid filled with silicon carbide particles reinforced high-temperature-resistant composite adhesive, press and move the wear-resistant tile up and down to eliminate the gap, and make the heat-resistant surface of the wear-resistant tile and the finned tube Stencil tightly bonded;

Step E, press the snap ring on the outer surface of the wear-resistant tile, insert its end into the notch on the wear-resistant tile ear, and weld the snap ring with the heating surface of the fin tube fin there, It is a film-type water-cooled wall with abrasion resistance on the heat-receiving surface, which is composed of finned tubes with heat-reduction on the heat-reduction surface.

According to some preferred embodiments of the present invention, in step C, a high-temperature-resistant composite adhesive reinforced with silicon carbide particles is filled into a mesh of a steel mesh welded on a heating surface of a finned tube and raised above the steel mesh. 1-2mm.

In some embodiments of the present invention, the steel mesh and the heating surface of the finned tube have the same size and shape.

Preferably, the steel plate is a stainless steel mesh that is resistant to high temperature abrasion.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are used to provide a further understanding of the present invention, and constitute a part of the description. Together with the embodiments of the present invention, the drawings are used to explain the present invention, and do not constitute a limitation on the present invention. In the drawings:

FIG. 1 is a schematic diagram of a finned tube with abrasion resistance on a heated surface in the present invention.

FIG. 2 is a schematic structural diagram of a wear-resistant tile in the present invention.

FIG. 3 is a schematic diagram of a finned tube covered with a high temperature abrasion resistant stainless steel mesh in a heating surface according to the present invention.

FIG. 4 is a schematic diagram of a wear-resistant slip ring in the present invention.

The meanings of the reference signs in the figure are as follows: 1 finned tube; 2 stainless steel mesh with high temperature abrasion resistance; 3 interlayers; 4 wear-resistant tiles; 5 snap rings; 11 fins; 41 ears on the wear-resistant tiles; 42 Notches on wear-resistant tile ears; 100 finned tubes with abrasion resistance on heated surfaces.

detailed description

In order to make the present invention easier to understand, the following describes the present invention in detail with reference to the accompanying drawings. However, before describing the invention in detail, it should be understood that the invention is not limited to the specific embodiments described. It should also be understood that terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

Unless otherwise defined, all terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, the preferred methods and materials are now described.

I. Terminology

The term "water-cooled wall" used in the present invention is also referred to as "water-cooled wall" or "water-cooled wall pipe". The steel pipe is usually laid vertically on the inner wall surface of the boiler furnace wall, which is mainly used to absorb the heat emitted by the flame and high temperature flue gas in the furnace.

The term “film-type water-cooled wall” (referred to as the film-type wall) used in the present invention refers to a water-cooled wall composed of flat steel (fins, fins, or butterflies) and an air-tight pipe panel welded side by side.

Abrasion refers to the destruction phenomenon caused by the combined effects of corrosion and abrasion of materials, and is also called erosion-corrosion. Abrasion is the result of mechanical action such as fluid motion. The flowing liquid or gas constantly erodes the surface of the material, not only directly abrading the material, but also destroying the protective film on the surface of the material, making the fresh material surface continuously contact with corrosive fluids, which accelerates corrosion effect. Abrasion is more severe when the fluid contains solid particles.

The term "fin" used in the present invention is also referred to as a fin or a butterfly, and is used to weld water-cooled wall tubes together to form a metal sheet of a fin-shaped tube.

The term "ear" as used in the present invention refers to a strip-shaped steel plate with the side edges of the wear-resistant tile in the longitudinal direction.

The term "finned tube" used in the present invention refers to a steel pipe with longitudinal fins used to prepare or constitute a membrane type water cooled wall, and here mainly refers to a single longitudinally finned steel pipe constituting a membrane type water cooled wall.

The term "inner surface" in the present invention refers to the side of the finned tube, wear-resistant tile, steel mesh or interlayer facing the axis.

The term "outer surface" in the present invention refers to the side of the finned tube, wear-resistant tile, steel mesh or interlayer facing away from the axis.

The terms "gap" and "gap" used in the present invention are used interchangeably.

The terms "welding" and "welding" used in the present invention can be used interchangeably.

The terms "wear-resistant slip ring" and "snap ring" used in the present invention can be used interchangeably.

The terms "join" and "join" used in the present invention are used interchangeably.

When explaining or describing elements of the invention, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "including", "containing", "including" and "having" are intended to be inclusive, meaning that there may be additional elements other than the listed elements.

The terms "about," "approximately," "substantially," and "mainly" described herein, when used in conjunction with a range of elements, concentrations, temperatures, or other physical or chemical properties or characteristics, cover what may be present in the attribute or characteristic. Changes in the upper and / or lower limits of the range include, for example, changes caused by rounding, measurement methods, or other statistical changes. As described herein, numerical values related to quantity, weight, etc., are defined as "about" which is the addition or subtraction of 10% of all values for each particular value. For example, the term "about 10%" should be understood as "9% to 11%".

II. Implementation Scheme

As mentioned earlier, in the existing anti-abrasion methods of boiler water-cooled wall tubes, anti-wear tiles are also called anti-wear covers, anti-wear plates, anti-wear protection tiles, anti-wear cover plates, anti-corrosion cover plates, boiler climbing pipes, Anti-wear pressure plate and other methods, compared with other water-cooled wall tube anti-wear laser cladding, surfacing wear-resistant anti-corrosion and thermal spray wear-resistant anti-corrosion coating methods, low cost, convenient operation, good anti-wear effect, but heat transfer efficiency Lower. In view of this, the present inventors have conducted a lot of researches on the technology for preventing abrasion of water-cooled wall tubes of boilers by using wear-resistant tiles.

The inventors have researched and found that, because the inner diameter of the wear-resistant tile is generally 1-5 mm larger than the outer diameter of the water-cooled wall pipe, the gap between the anti-wear tile and the pipe wall will seriously affect the heat exchange efficiency of the water-cooled wall pipe. Further research found that fixing the wear-resistant tile on the water-cooled wall pipe by the glue fixing method can eliminate the gap between the wear-resistant tile and the water-cooled wall pipe wall, which can significantly reduce the corrosion and wear of the water-cooled wall and prolong the service life of the water-cooled wall. Significantly improve the heat exchange efficiency of water-cooled walls with anti-wear tiles. The present invention has been made based on the above findings.

Therefore, the film-type water-cooled wall with anti-abrasion of the heating surface according to the first aspect of the present invention includes at least two fin tubes with anti-abrasion on the heating surface, and the fin tubes are welded in a row by fins. The finned tube with anti-abrasion on the heating surface is shown in FIG. 1. The finned tube 100 with anti-abrasion on the heating surface includes a finned tube 1 and an anti-abrasion layer covering the heating surface of the finned tube 1. The abrasive layer includes an interlayer 3 covering the heating surface of the finned tube 1, an anti-wear tile 4 covering the outer surface of the interlayer 3, and an anti-wear slip ring 5 provided on the outer surface of the anti-wear tile 4, the anti-wear tile 4 and the heating surface of the finned tube 1 are joined by the interlayer 3 and tightly joined by the wear-resistant slip ring 5.

In the present invention, the wear-resistant tile is fixed on the heating surface of the finned tube through a sandwich and the wear-resistant plate snap ring to tightly combine the two. In the present invention, such a connection is made between the wear-resistant tile and the heated surface of the finned tube. And the fixing method is called the sandwich fixing method.

There is no gap between the heating surface of the finned tube and the wear-resistant tile connected and fixed by the above-mentioned glue fixing method. Therefore, while improving the anti-abrasion strength of the heating surface of the finned tube, the heat exchange efficiency of the anti-abraded finned tube can be greatly improved.

It can be seen from the above that the interlayer in the present invention is a key factor for forming a film-type water-cooled wall with a high heat exchange efficiency and abrasion resistance on the heated surface provided by the present invention. The heating surface of the finned tube of the film-type water-cooled wall with anti-abrasion on the heating surface and the anti-wear tile are tightly connected through an interlayer and an anti-wear tile snap ring. In order to effectively reduce and eliminate the gap between the wear-resistant tile and the heating surface of the finned tube and improve heat exchange efficiency, the present invention uses silicon carbide particles reinforced high-temperature-resistant composite adhesive to fill the gap to form an interlayer. Silicon carbide is a wear-resistant material with good thermal conductivity and thermal stability. Its thermal conductivity is 83.6W / (m · K), while the thermal conductivity of ordinary carbon steel is about 45W / (m · K), and the thermal conductivity of stainless steel is only 16W / (m · K). In addition, the silicon carbide particle-reinforced high-temperature resistant material is used as an interlayer, which can play an anti-abrasion effect when the wear-resistant tile is worn through, prolong the service life of the membrane wall, and improve the economic efficiency of the power plant. At the same time, silicon carbide particles reinforced high temperature resistant materials are used as adhesives, which have low density, stable chemical properties, and microhardness of 2840-3320kg / mm ² , high hardness and abrasion resistance, specific gravity of 3.20-3.25, light weight, and resistance The degree of grinding is 6-7 times that of ordinary wear-resistant materials. The gap between the wear-resistant tile and the finned tube is filled with a high-temperature-resistant adhesive reinforced by silicon carbide particles, which tightly combines the wear-resistant tile and the heated surface of the finned tube with high heat exchange efficiency and long service life.

Those skilled in the art should understand that silicon carbide particle reinforced high temperature resistant adhesives that can meet the above requirements can be used in the present invention. In some embodiments, commercially available silicon carbide particle-reinforced high-temperature-resistant adhesives can be directly used, for example, KN1000 anti-resistant brand high-temperature abrasion-resistant adhesive (Beijing Naimo Co., whose temperature can reach 1200 ° C), TXG60181500 ° C high-temperature glue (Dongguan City) Yantai Chemical Technology Co., Ltd.), TXG-6019TXG60181500 ℃ high temperature glue (Dongguan Yantai Chemical Technology Co., Ltd.), 1730 ℃ ultra high temperature sealant and so on.

In some preferred embodiments of the present invention, the silicon carbide particle-reinforced high-temperature-resistant composite adhesive is prepared by using the silicon carbide particles and the high-temperature-resistant adhesive in a weight ratio of 3: 1, wherein the high-temperature-resistant adhesive includes, for example, 1280 ℃ high temperature resistant sealant, Den Braven Sealants 1200 ℃ (Dutch swallow high transparent sealant, high temperature resistance 1200 ℃) and so on.

In order to prevent the high-temperature-resistant adhesive reinforced by silicon carbide particles from falling off after the failure of the wear-resistant tile and improve the bonding strength of the anti-wear layer, in the present invention, a 1-5 mm thick stainless steel mesh is pressed into the same shape and size as the finned tube. Welded on the fins of the finned tube, the high temperature resistant adhesive reinforced by silicon carbide particles fills the pores of the expanded steel mesh with pressure, eliminating the gap between the wear-resistant tile and the heating surface of the finned tube, forming an interlayer, which can improve wear resistance The strength of the combination of the tile and the finned tube improves the anti-abrasion performance and service life of the finned tube. For example, in some embodiments of the present invention, the interlayer 3 is composed of a steel mesh 2 filled with silicon carbide particles to strengthen a high-temperature-resistant composite adhesive, and the steel mesh 2 is welded to the fins on the heating surface of the fin tube 1 11 on.

FIG. 2 is a schematic diagram of a finned tube covered with a high-temperature-resistant abrasion-resistant stainless steel mesh in the heating surface of the present invention. As shown in FIG. 2, the steel mesh 2 is welded to the fins 11 on the heated surface of the finned tube 1. In some embodiments, the thickness of the expanded metal mesh is 1-5 mm; preferably, the expanded metal mesh 2 is a high-temperature resistant stainless steel expanded metal, for example, a stainless steel expanded metal such as 1Gr25Ni20Si2 or Ni60A. In some examples, the thickness of the interlayer is 1-6 mm.

In the present invention, there is no gap between the heating surface of the finned tube 1 and the anti-wear pad 4. Specifically, there are no gaps between the heating surface of the finned tube 1 and the inner surface of the interlayer 3, between the outer surface of the interlayer 3 and the inner surface of the wear-resistant tile 4, and inside the interlayer 3.

Preferably, in order to further improve the bonding strength of the anti-abrasive layer, the present invention performs sandblasting and roughening on the heated surface of the finned tube 1 before welding the steel mesh, and then welds the steel plate on the heated surface of the sandblasted roughened surface. Net, and filled with adhesive, so as to better prevent the high temperature resistant adhesive reinforced by silicon carbide particles after the wear resistance of the wear-resistant tiles, which can further improve the bonding strength of the wear-resistant tiles and the finned tube, and improve the anti-abrasion performance of the finned tube And service life. Therefore, in the present invention, the heat-receiving surface of the finned tube has a certain surface roughness after being subjected to sandblasting and roughening treatment.

In the present invention, there is no particular limitation on the sandblasting and roughening treatment process. For example, the sandblasting and roughening treatment can be performed on the heating surface of the finned tube using a conventional sandblasting treatment process in the art. In some embodiments, the surface roughness of the heated surface of the finned tube subjected to sandblasting is 30-80 microns, preferably 40-75 microns.

In the present invention, the radius of the inner surface of the wear-resistant tile is 1-5 mm larger than the radius of the outer surface of the finned tube. The thickness of the anti-wear pad 4 is 1-5 mm. In order to prevent the abrasion failure of the membrane type wall fin, an ear is provided on one side of the anti-wear tile, and the ear is used to protect the membrane type wall fin.

FIG. 3 is a schematic structural diagram of a wear-resistant tile in the present invention. As shown in FIG. 3, one side of the wear-resistant tile 4 is provided with an ear 41, the width of the ear 41 is the same as the width of the fin 11 of the fin tube 1, and the wear-resistant tile is provided on the ear 41 Notch 42 of the snap ring.

In the present invention, the material of the anti-wear tile is a stainless steel plate with excellent high-temperature abrasion resistance. It is a rolled steel plate, which is used as a raw material of the anti-wear tile and other water-cooled materials such as micro-welding, laser cladding, CMT surfacing The coating prepared by the wall anti-abrasion method is denser, has fewer defects, has higher cohesive strength, and has a longer service life compared to the material. In some embodiments of the present invention, the material of the anti-wear pad 4 is a stainless steel plate resistant to high temperature abrasion, for example, a stainless steel plate resistant to high temperature abrasion such as model 1Gr25Ni20Si2 or Ni60A.

In the present invention, in order to further improve the bonding strength of the anti-abrasion layer, the high-temperature-resistant adhesive reinforced with silicon carbide particles is used, and even the high-temperature-resistant adhesive reinforced with silicon carbide particles filled in the steel mesh is used to combine and fix the anti-wear tile on the fins. After the heated surface of the finned tube, the wear-resistant tile is pressed by the wear-resistant slip ring, and the wear-resistant slip ring and the fin of the fin tube are welded and strengthened.

In some embodiments, after the high-temperature-resistant adhesive reinforced with silicon carbide particles, or even the high-temperature-resistant adhesive with silicon carbide particles filled into the expanded metal mesh are combined and fixed on the heating surface of the finned tube, The wear-resistant snap ring presses the wear-resistant slip in turn, and the wear-resistant slip ring and the fins of the fin tube are reinforced by welding.

FIG. 4 is a schematic diagram of a wear-resistant slip ring in the present invention. In the present invention, an end portion of the wear-resistant slip ring 5 is inserted into a notch 42 on the wear-resistant slip ear 41 and is welded to the fin 11 of the fin tube 1 at the end.

In some embodiments of the present invention, the inner diameter of the anti-wear tile snap ring 5 is the same as the outer diameter of the anti-wear shoe 3, with a width of 30mm-50mm and a thickness of 3-5mm. Preferably, the material of the anti-wear slip ring 5 is a stainless steel plate resistant to high temperature abrasion, for example, a stainless steel plate resistant to high temperature abrasion such as 1Gr25Ni20Si2 or Ni60A.

In the present invention, since the present invention can choose to prepare wear-resistant tiles of different materials and thicknesses according to actual needs, and also to select the thickness of the interlayer, the thickness of the wear-resistant layer of the wear-resistant finned tube of the present invention can be Arbitrarily adjusted according to user needs.

The second aspect of the present invention provides a method for preparing the film-type water-cooled wall with anti-abrasion of the heating surface. On the one hand, in view of improving the anti-abrasion performance of the film-type water-cooled wall's heating surface and prolonging the service life, the method can be understood as a film-type water-cooled wall Method for preventing abrasion of heating surface; On the other hand, from the perspective of improving the heat exchange efficiency of film-type water-cooled wall with anti-abrasion on the surface of heating, this method can be understood as the heating surface of finned tube of film-type water-wall with anti-abrasion on heating surface Method for fixing wear-resistant tile; the method includes:

Step A, sandblasting and roughening the heated surface of the finned tube 1 on the film-type water-cooled wall 100;

In step B, a steel mesh 2 having the same size and shape as the heating surface of the fin tube 1 is welded to the heating surface of the fin tube 1 by welding on the fin 11 of the fin tube 1, as shown in FIG. 2 Shown

Step C, filling the silicon carbide particle-reinforced high-temperature-resistant composite adhesive into the grid of the expanded metal mesh 2 welded to the heating surface of the finned tube 1 under manual pressure, and making it 1-2 mm higher than the expanded metal mesh;

Step D, buckle the wear-resistant tile 4 (as shown in FIG. 3) on the steel mesh 2 filled with silicon carbide particles reinforced high-temperature-resistant composite adhesive in the grid, press the wear-resistant tile 4 up and down to eliminate the gap, Tightly bonding the wear-resistant tile 4 with the expanded steel mesh 2 on the heating surface of the finned tube 1;

Step E, press the snap ring 5 (as shown in FIG. 4) on the outer surface of the wear-resistant tile 4, insert its end into the notch 42 on the ear 41 of the wear-resistant tile 4, and use the snap ring at this place 5 is welded to the heating surface of the fin tube 1 and the fin 11 to form a film-type water-cooled wall with a heating surface and abrasion resistance formed by connecting the fin tubes 100 (shown in FIG. 1) with abrasion resistance on the heating surface.

In step A, there is no particular limitation on the sandblasting roughening process. For example, a conventional sandblasting process in the art may be used to sandblast the roughened surface of the finned tube. In some embodiments, the surface roughness of the heated surface of the finned tube subjected to sandblasting is 30-80 microns, preferably 40-75 microns.

In some embodiments, the thickness of the expanded metal mesh is 1-5 mm; preferably, the expanded metal mesh 2 is a high-temperature resistant stainless steel expanded metal, for example, a stainless steel expanded metal such as 1Gr25Ni20Si2 or Ni60A.

In some embodiments, the thickness of the interlayer is 3-6 mm.

An ear 41 is provided on one side of the wear-resistant tile 4 (as shown in FIG. 3), and the width of the ear 41 is the same as the width of the fin 11 of the fin tube 1. The gap 42 of the Waka ring.

In some embodiments of the present invention, the radius of the inner surface of the wear-resistant tile 4 is larger than the radius of the outer surface of the finned tube 1 by 1-5 mm. The thickness of the anti-wear pad 4 is 1-5 mm. Preferably, the material of the anti-wear pad 4 is a stainless steel plate resistant to high temperature abrasion, for example, a stainless steel plate resistant to high temperature abrasion such as 1Gr25Ni20Si2 or Ni60A.

The end of the wear-resistant slip ring 5 (as shown in FIG. 4) is inserted into a notch 42 on the ear 41 of the wear-resistant slip 4 and is welded to the fin 11 of the fin tube 1 there.

In some embodiments of the present invention, the inner diameter of the anti-wear tile snap ring 5 is the same as the outer diameter of the anti-wear shoe 3, and the width is 30mm-50mm.

In other embodiments of the present invention, the thickness of the anti-wear slip ring 5 is 3-5 mm. Preferably, the material of the anti-wear slip ring 5 is a stainless steel plate resistant to high temperature abrasion, for example, a stainless steel plate resistant to high temperature abrasion such as 1Gr25Ni20Si2 or Ni60A.

The film-type water-cooled wall with anti-abrasion on the heated surface prepared by the above method has high heat transfer efficiency, good anti-abrasion performance and long service life. The service life of the film-type water-cooled wall with anti-abrasion on the heating surface can be adjusted by adjusting the thickness of the interlayer and the anti-wear tile according to the requirements of the user.

III. Detection methods

The porosity of the adhesive coating (interlayer) in the present invention is monitored according to GB / T 17721-1999 (metal porosity test of the coating, corresponding to the international standard ISO 10309: 1994).

The heat exchange efficiency of the water-cooled wall tube in the present invention is monitored according to GB / T 27698.1-2011 (test method for performance of heat exchangers and heat transfer elements, corresponding to the international standard ISO 15547-1: 2005).

In the present invention, the surface roughness of the heating surface of the finned tube is measured using an anchor texture meter (PCWI 0918, PCWI, Australia).

In the present invention, the anti-abrasion performance of the water-cooled wall tube heating surface is directly detected by using the actual consumption rate in production.

IV, beneficial effects

(1) The quality of the metal anti-wear layer is good: the raw material of the anti-wear tile is rolled steel plate, and the coating prepared by other water-cooled wall anti-abrasion methods such as micro-welding, laser cladding, CMT overlay welding is denser, less defective, and less High polymer strength and long service life.

(2) High material utilization, environmental protection and energy saving: Micro-fusion welding consists of three processes, which are both environmental pollution and power consumption, including sand blasting, thermal spraying and remelting. The thermal spray deposition rate is about 70%. The anti-wear tile is formed by the press without pollution, and the scrap can be pressed into an anti-wear tile snap ring. The material utilization rate is over 98%, the power consumption is small, and the environment protection and energy saving.

(3) Low cost and good economic benefits: The thickness and material of the wear-resistant tile can be arbitrarily adjusted according to user needs. Compared with micro-fusion welding and other processes, if the same anti-abrasive material and the same coating thickness are selected, because the process of the present invention is simple, the equipment investment is small, and the efficiency is high, the cost of anti-abrasion using the technology of the present invention is much lower than that of micro-welding. Welding, CMT, laser cladding and other processes.

(4) High heat exchange efficiency of boiler. Long service life: Existing water-cooled wall pipe anti-wear tile protection technology. There is a gap between the anti-wear tile and water-cooled wall pipe, and the boiler heat exchange efficiency is low. A significant advantage of the present invention is that the gaps are filled with high temperature resistant adhesive reinforced with silicon carbide particles. Silicon carbide is a wear-resistant material with good thermal conductivity and thermal stability. Its thermal conductivity is 83.6W / (m · K), while the thermal conductivity of ordinary carbon steel is about 45W / (m · K), and the thermal conductivity of stainless steel is only 16W / (m · K). As a boiler heat exchanger, the combustible consumption is reduced by 20W / (m · K)%, the fuel is saved by 35%, and the productivity is increased by 20-30%. In addition, when the wear-resistant tile is worn through as an interlayer, it can play an anti-abrasion effect, prolong the service life of the membrane wall, and improve the economic efficiency of the power plant. High temperature resistant adhesive reinforced with silicon carbide particles has low density, light weight, stable chemical properties, microhardness of 2840-3320kg / mm ² , high hardness and wear resistance, specific gravity of 3.20-3.25, light weight, and wear resistance is ordinary. 6-7 times the material. The gap between the wear-resistant tile and the water-cooled wall tube is filled with high-temperature-resistant adhesive reinforced by silicon carbide particles, which is compacted by the wear-resistant slip ring, tightly combined, with high heat exchange efficiency and long service life.

(5) High bonding strength of the anti-wear layer: In order to prevent the high-temperature-resistant adhesive reinforced by silicon carbide particles from falling off after the wear of the anti-wear tile, the heating surface of the water-cooled wall pipe is grit-blasted before gluing, and a stainless steel plate with a thickness of 3-5 mm is used. The mesh is pressed into a wear-resistant tile shape and welded to the membrane-type wall fins. The high temperature resistant adhesive reinforced by silicon carbide particles is used to pressure-fill the pores of the steel mesh. The wear-resistant tile is fixed in addition to the high-temperature-resistant adhesive reinforced by silicon carbide particles and is bonded to the membrane wall. After the wear-resistant tile is pressed by the wear-resistant tile snap ring, the wear-resistant tile snap ring is welded and strengthened with the membrane wall fins.

(6) Simple process and high productivity: anti-wear tile, expanded wire mesh, and clamp forming can all be mechanized and mass-produced at high speed. The steel mesh is pressed into the shape of a wear-resistant tile, which can be pressed in a large area at one time, and can be welded to the fins in a large area at one time. Applying silicon carbide particle-reinforced composite material adhesive and welding the wear-resistant tile snap ring between the wear-resistant tile and the membrane wall is simple, mature, and fast. The membrane wall is not deformed during the construction process, and subsequent shaping is not required, and hundreds of square meters can be completed every day. Compared with the existing technologies such as micro-welding, the daily output is about several times more.

(7) High-temperature adhesives for coke oven maintenance have good high-temperature performance: the product is non-toxic, odorless, and has strong thermal adaptability; high mechanical strength: it can be used at a high temperature of 1100 ° C. Combined with silicon carbide, it has high strength, abrasion resistance, earthquake resistance, spalling resistance, and durability. It is convenient for construction on site: construction is not affected by seasonal climate and temperature, and it is fast and convenient. It has a long service life. Its life is 7-10 times that of the traditional high-temperature resistant rubber currently used in China; fire resistance: 1790 ° C; moisture-soluble amount: 2300-2600Kg / m ³ ; bulk density: 3.22g / cm ³ ; load softening temperature: 1420 ° C; Thermal stability times ≥20: (800-950 ° C); apparent porosity 19%: compressive strength MPa: 80.2 (500 ° C x 2h) 42.3 (1000 ° C x 2h) 38.3 (1400 ° C x 2h); bonding time : 35 seconds; bond strength: 0.3 MPa (900 ° C x 24h) 0.2 MPa (1100 ° C x 3h); maximum linear expansion rate: ± 0.26%. The adhesive is characterized by good high temperature resistance and can withstand high temperatures of 1100 ° C.

Compared with the existing water-cooled wall pipe hanging anti-wear protection technology, the present invention takes advantage of its simple structure and convenient construction. The high-temperature resistance is enhanced by coating silicon carbide particles between the anti-wear and the heating surface of the membrane wall Adhesive overcomes the disadvantages of low heat transfer efficiency of traditional anti-wear shoes. Significantly increase the strength and service life of the wear-resistant tile and water-cooled wall pipe, reduce the frequency and cost of maintenance, and improve the economic efficiency of the enterprise.

Examples

In order to make the present invention easier to understand, the present invention will be further described in detail with reference to the accompanying drawings and embodiments. These embodiments serve only for illustrative purposes and are not limited to the scope of application of the present invention. The raw materials or components used in the present invention can be obtained through commercial means or conventional methods unless otherwise specified.

Example 1:

The wear-resistant tile is joined to the heating surface of the finned tube of the film-type water-cooled wall to manufacture a film-type water-cooled wall whose heating surface is anti-abrasion.

(1) Sandblasting the heating surface of the fin tube 1 on the film-type water-cooled wall, so that the surface roughness of the heating surface of the fin tube is 40 microns (PCWI 0918 anchor pattern instrument, PCWI, Australia);

(2) Welded a steel mesh 2 (material: 1Gr25Ni20Si2 or Ni60A, thickness: 1mm) having the same size and shape as the heating surface of the fin tube 1 by welding on the fin 11 of the fin tube 1 to the fin. The heating surface of the sheet tube 1 is shown in FIG. 2;

(3) The KN1000 anti-brand high-temperature wear-resistant adhesive or silicon carbide particles are mixed with the 1280 ° C high-temperature sealant at a ratio of 3: 1, and the high-temperature-resistant composite adhesive reinforced with silicon carbide particles is pressed and welded in a mechanically applied manner. The mesh of the expanded metal mesh 2 on the heating surface of the finned tube 1 is 1 mm higher than the expanded metal mesh;

(4) The wear-resistant tile 4 (made of 1Gr25Ni20Si2 or Ni60A) is buckled on the steel mesh 2 filled with silicon carbide particles reinforced high-temperature-resistant composite adhesive in the grid, and the wear-resistant tile 4 is shifted up and down to eliminate the gap. Tightly bonding the wear-resistant tile 4 with the expanded steel mesh 2 on the heating surface of the finned tube 1;

The radius of the inner surface of the wear-resistant tile 4 is larger than the radius of the outer surface of the finned tube 1 by 1 mm, and the thickness of the wear-resistant tile 4 is 1 mm.

(5) Press the snap ring 5 (made of 1Gr25Ni20Si2 or Ni60A) on the outer surface of the wear-resistant tile 4 and insert its end into the notch 42 on the ear 41 of the wear-resistant tile 4 and use the retaining ring 5 is welded to the heating surface of the fin tube 1 and the fin 11 to form a film-type water-cooled wall with a heating surface and abrasion resistance formed by connecting the fin tubes 100 (shown in FIG. 1) with abrasion resistance on the heating surface.

The inner diameter of the anti-wear tile retaining ring 5 is the same as the outer diameter of the anti-wear tile 3, with a width of 30 mm and a thickness of 3 mm.

The prepared film-type water-cooled wall with anti-abrasion on the heating surface includes at least two fin tubes with anti-abrasion on the heating surface, and each fin tube is welded in a row by fins. The finned tube with anti-abrasion on the heating surface is shown in FIG. 1. The finned tube 100 with anti-abrasion on the heating surface includes a finned tube 1 and an anti-abrasion layer covering the heating surface of the finned tube 1. The abrasive layer includes an interlayer 3 covering the heating surface of the finned tube 1, an anti-wear tile 4 covering the outer surface of the interlayer 3, and an anti-wear slip ring 5 provided on the outer surface of the anti-wear tile 4, the anti-wear tile 4 and the heating surface of the finned tube 1 are joined by the interlayer 3 and tightly joined by the wear-resistant slip ring 5.

According to GB / T 17721-1999 (Metal Cover Porosity Test), the porosity of the adhesive coating (interlayer) in this example was tested, and the results showed that the interlayer's porosity was small and could be basically ignored.

According to GB / T 27698.1-2011 (Test method for performance of heat exchangers and heat transfer elements), the heat exchange efficiency of the film-type water-cooled wall or finned tube with anti-abrasion on the heating surface in this embodiment is tested, and the results show that in this embodiment, The heat transfer efficiency of the film-type water-cooled wall or finned tube with anti-abrasion on the heating surface is 4 times that of the film-type water-cooled wall with the original anti-wear tile.

The actual consumption rate in production is used to directly detect the abrasion resistance of the film-type water-cooled wall on the heated surface in this embodiment, and the results show that the film-type water-cooled wall in this embodiment has a good abrasion resistance.

Example 2:

(1) Sandblasting the heated surface of the finned tube 1 on the film-type water-cooled wall, so that the surface roughness of the heated surface of the finned tube is 75 micrometers (PCWI 0918 anchor pattern meter, Australian PCWI company);

(2) Welded a steel mesh 2 (material: 1Gr25Ni20Si2 or Ni60A, thickness: 5mm) with the same size and shape as the heating surface of the fin tube 1 by welding on the fin 11 of the fin tube 1 The heating surface of the sheet tube 1 is shown in FIG. 2;

(3) press the silicon carbide particle reinforced high-temperature-resistant composite adhesive into the grid of the expanded metal mesh 2 welded to the heating surface of the finned tube 1 by mechanically applying pressure, and make it 2 mm higher than the expanded metal mesh;

The radius of the inner surface of the wear-resistant tile 4 is larger than the radius of the outer surface of the finned tube 1 by 5 mm, and the thickness of the wear-resistant tile 4 is 5 mm.

The inner diameter of the anti-wear tile retaining ring 5 is the same as the outer diameter of the anti-wear tile 3, with a width of 50 mm and a thickness of 5 mm.

According to GB / T 17721-1999 (Metal Cover Porosity Test), the porosity of the adhesive coating (interlayer) in this example is tested, and the results show that the interlayer's porosity is small and can be basically ignored.

It should be noted that what has been described above are only preferred embodiments of the present invention, and the above specific embodiments are not a limitation on the present invention. There are many adhesive formulations and bonding processes. Any person skilled in the art can use any The finishing, modification, or equivalent replacement made by connecting the water-cooled wall pipe and the anti-wear tile with an adhesive formula and the anti-wear tile connection technology all belong to the protection scope of the present invention.

Claims

A film-type water-cooled wall with anti-abrasion on a heating surface includes at least two fin tubes with anti-abrasion on a heating surface, and each fin tube is welded in a row by fins, wherein the abrasion-proof fins on the heating surface The tube includes a finned tube and an anti-abrasion layer covering the heating surface of the finned tube. The anti-abrasion layer includes an interlayer covered on the heating surface of the finned tube, an anti-wear tile covering the outer surface of the interlayer, and An anti-wear shoe snap ring on the outer surface of the shoe, the anti-skid shoe and the heating surface of the finned tube are bonded by a sandwich, and tightly joined by the anti-skid shoe ring.
The film-type water-cooled wall according to claim 1, wherein the interlayer is composed of a steel mesh filled with silicon carbide particles to strengthen a high-temperature-resistant composite adhesive; preferably, the silicon carbide particles are reinforced to a high-temperature-resistant composite The adhesive is prepared by using silicon carbide particles and a high-temperature-resistant adhesive in a weight ratio of 3: 1; the high-temperature-resistant adhesive includes 1280 ° C high-temperature sealant and / or Den Braven Sealants 1200 ° C.
The film-type water-cooled wall according to claim 2, characterized in that the expanded metal mesh is welded to the fins on the heating surface of the finned tube, preferably the expanded metal mesh has a thickness of 1-5 mm; further preferably, the expanded metal mesh is resistant to high temperature abrasion. Stainless steel expanded metal.
The film-type water-cooled wall according to claim 1, wherein there is no gap between the heating surface of the fin tube and the wear-resistant tile; preferably, there is a sandwich between the heating surface of the fin tube and the inner surface of the interlayer. There are no gaps between the outer surface and the inner surface of the wear-resistant tile, as well as inside the sandwich.
The film-type water-cooled wall according to claim 2, wherein there is no gap between the heating surface of the fin tube and the wear-resistant tile; preferably, there is an interlayer between the heating surface of the fin tube and the inner surface of the interlayer. There are no gaps between the outer surface and the inner surface of the wear-resistant tile, as well as inside the sandwich.
The film-type water-cooled wall according to claim 3, wherein there is no gap between the heating surface of the fin tube and the wear-resistant tile; preferably, there is an interlayer between the heating surface of the fin tube and the inner surface of the interlayer. There are no gaps between the outer surface and the inner surface of the wear-resistant tile, as well as inside the sandwich.
The membrane-type water-cooled wall according to any one of claims 1-6, wherein one side of the wear-resistant tile is provided with an ear, and the width of the ear is the same as the width of the fin of the fin tube, And the ear is provided with a gap for installing a wear-resistant slip ring.
The membrane-type water-cooled wall according to any one of claims 1-6, wherein a radius of an inner surface of the wear-resistant tile is 1-5 mm larger than a radius of an outer surface of the finned tube, The thickness is 1-5 mm; preferably, the material of the anti-wear tile is a stainless steel plate resistant to high temperature abrasion.
The membrane-type water-cooled wall according to claim 7, wherein the radius of the inner surface of the wear-resistant tile is larger than the radius of the outer surface of the finned tube by 1-5 mm, and the thickness of the wear-resistant tile is 1-5 mm; Preferably, the material of the anti-wear tile is a stainless steel plate resistant to high temperature abrasion.
The membrane-type water-cooled wall according to any one of claims 1-6, wherein an end of the wear-resistant slip ring is inserted into a notch on the wear-resistant ear, and is connected with the fin there. The fins of the tubes are welded together; preferably, the inner diameter of the anti-wear slip ring is the same as the outer diameter of the anti-wear slip, the width is 30-50mm, and the thickness of the anti-wear slip ring is 3-5mm; further preferably, The material of the anti-abrasion slip ring is a stainless steel plate resistant to high temperature abrasion.
The membrane-type water-cooled wall according to claim 7, wherein an end of the wear-resistant slip ring is inserted into a notch on the wear-resistant ear and welded to the fin of the finned tube there. ; Preferably, the inner diameter of the wear-resistant slip ring is the same as the outer diameter of the wear-resistant slip, the width is 30-50mm, and the thickness of the wear-resistant slip ring is 3-5mm; further preferably, the wear-resistant slip is The material of the ring is a stainless steel plate resistant to high temperature abrasion.
The membrane-type water-cooled wall according to claim 8, characterized in that an end of the wear-resistant slip ring is inserted into a gap on the wear-resistant ear and welded to the fin of the finned tube there. ; Preferably, the inner diameter of the wear-resistant slip ring is the same as the outer diameter of the wear-resistant slip, the width is 30-50mm, and the thickness of the wear-resistant slip ring is 3-5mm; further preferably, the wear-resistant slip is The material of the ring is a stainless steel plate resistant to high temperature abrasion.
The membrane-type water-cooled wall according to claim 9, wherein the end of the wear-resistant slip ring is inserted into a notch on the wear-resistant ear and welded to the fin of the finned tube there. ; Preferably, the inner diameter of the wear-resistant slip ring is the same as the outer diameter of the wear-resistant slip, the width is 30-50mm, and the thickness of the wear-resistant slip ring is 3-5mm; further preferably, the wear-resistant slip is The material of the ring is a stainless steel plate resistant to high temperature abrasion.
A method for preparing a film-type water-cooled wall with anti-abrasion on a heated surface includes:

Step A, sandblasting and roughening the heating surface of the finned tube on the film-type water-cooled wall;

Step B, welding a steel mesh having the same size and shape as the membrane wall on the heating surface of the fin tube by welding on the fins of the fin tube;

Step C, filling a silicon carbide particle-reinforced high-temperature-resistant composite adhesive into a grid of a steel mesh welded on a heating surface of the finned tube;

Step D, buckle the wear-resistant tile on the steel mesh of the grid filled with silicon carbide particles reinforced high-temperature-resistant composite adhesive, press and move the wear-resistant tile up and down to eliminate the gap, and make the heat-resistant surface of the wear-resistant tile and the finned tube Stencil tightly bonded;

Step E, press the snap ring on the outer surface of the anti-wear tile, insert the end into the notch on the anti-wear tile ear, and weld the snap ring to the heated surface of the fin tube fin at the end to make it heated The film-type water-cooled wall with anti-abrasion on the heating surface is formed by the surface anti-abrasion fin tubes connected to each other.
The method according to claim 14, characterized in that the expanded metal mesh and the heating surface of the finned tube have the same size and shape; preferably, the thickness of the expanded metal mesh is 1-5 mm; The material of said expanded metal is high temperature resistant stainless steel.
The method according to any one of claims 14, wherein ears are provided on one side of the wear-resistant tile, and the width of the ears is the same as the width of the fins of the fin tube, and the ears are provided on the ears. There are gaps; preferably, the material of the wear-resistant tile is a stainless steel plate resistant to high temperature abrasion; further preferably, the radius of the inner surface of the wear-resistant tile is 1-5 mm larger than the radius of the outer surface of the finned tube, The thickness of the abrasive tile is 1-5mm.
The method according to any one of claims 15 to 15, wherein ears are provided on one side of the wear-resistant tile, and the width of the ears is the same as the width of the fins of the fin tube, and the ears are provided on the ears. There are gaps; preferably, the material of the wear-resistant tile is a stainless steel plate resistant to high temperature abrasion; further preferably, the radius of the inner surface of the wear-resistant tile is 1-5 mm larger than the radius of the outer surface of the finned tube, The thickness of the abrasive tile is 1-5mm.
The method according to any one of claims 14 to 17, characterized in that the end of the wear-resistant slip ring is inserted into a notch on the wear-resistant ear and is connected with the fin of the finned tube there. Sheet-phase welding; preferably, the material of the anti-wear slip ring is a stainless steel plate resistant to high temperature abrasion; further preferably, the inner diameter of the anti-wear slip ring is the same as the outer diameter of the anti-wear slip, and the width is 30-50mm The thickness of the wear-resistant slip ring is 3-5mm.
The method according to any one of claims 14 to 17, characterized in that, in step C, a high-temperature-resistant composite adhesive reinforced with silicon carbide particles is filled into a grid of a steel mesh welded to the heating surface of the finned tube. Inside and make it 1-2mm higher than the expanded metal.
The preparation method according to claim 18, wherein in step C, a high-temperature-resistant composite adhesive reinforced with silicon carbide particles is filled into a mesh of a steel mesh welded on a heating surface of a finned tube, and the 1-2mm above the expanded metal mesh.