Flexible expansion joint for desulfurization flue system and on-site installation method

Abstract

The present invention relates to a high temperature resistant and corrosion resistant flexible expansion joint for a desulfurization flue system and an on-site installation method, which replaces the original skin expansion joint. The flange sealing surface of the flexible expansion joint adopts a double sealing structure of adhesive bonding and compression sealing strip. During on-site installation, the flange surface of the flue expansion joint is cleaned and polished to make the surface free of dirt and rust, and then the adhesive is applied, the polymer flexible plate is installed, and the compression strip is installed and fastened with bolts. Advantages: The manufactured desulfurization flue expansion joint has a reliable sealing structure, simple installation and operation, flexible and maneuverable, and low price. It not only has excellent chemical medium resistance, anti-aging performance, and effective resistance and absorption of stress or displacement caused by mechanical vibration, and the service life meets the design specification requirements, but also can be used for the configuration of newly built desulfurization flue system devices, and is more suitable for the rapid maintenance or replacement of old expansion joints.

Description

Technical Field

[0001] The invention relates to a high temperature resistant and corrosion resistant flexible expansion joint arranged at the connection between a flue and a desulfurization tower, which replaces the original skin expansion joint and belongs to the field of expansion joint manufacturing. Background Art

[0002] Environmental protection requires that the industrial waste gas emission system must purify the flue gas (desulfurization) before it can be discharged into the atmosphere, as follows Figure 4 As shown. The system consists of five parts: boiler flue gas → original flue (flue from boiler to desulfurization tower) → desulfurization in desulfurization tower → clean flue (flue from the top of desulfurization tower to chimney) → chimney discharge. Therefore, when designing the desulfurization system, one or more expansion joints must be installed between the original flue and the desulfurization tower, and between the desulfurization tower and the clean flue, respectively, to adjust and absorb the displacement or vibration caused by thermal expansion and contraction or other movements between the flue and the desulfurization tower, and the flue gas cannot leak out of the flue. Figure 1 The positions A and B in the figure are the schematic diagrams of the positions of the two expansion joints. The expansion joints currently used are mostly made of glass fiber fabric coated with corrosion-resistant coatings, commonly known as skins. The main disadvantages are: the skins have insufficient aging resistance and sealing performance, poor elasticity and fatigue performance, resulting in smoke leakage, and failure of the expected sealing and anti-corrosion functions. Moreover, the expansion joint must be equipped with flanges of the same size as the flue, and the structural accessories are also relatively large. When replacing, production must be stopped, and the operation is relatively troublesome, which brings inconvenience and economic losses to the user's normal production. It cannot meet the requirements of design and user use. Summary of the invention

[0003] Design purpose: To avoid the shortcomings of the background technology, a high temperature resistant and corrosion resistant flexible expansion joint and on-site installation method for the desulfurization flue system is designed at the connection between the flue and the desulfurization tower to replace the original skin expansion joint.

[0004] Design scheme: In order to achieve the above design objectives. 1. The present invention adopts a flexible polymer composite material that can withstand high temperature and corrosion for a long time, improves the elasticity and fatigue performance of the original material, and provides a large displacement space in the structure, ensuring that the flue has sufficient thermal expansion and contraction positions and vibrations that may be generated by other movements, thereby extending the service life of the expansion joint. 2. The flange sealing surface adopts a double sealing structure of adhesive bonding and an external compression sealing strip to ensure that the flue sealing surface does not leak smoke, the sealing is safe and reliable, and the operation is simple and convenient. 3. The L-shaped support liner is adopted to eliminate the drain pipe at the bottom of the original expansion joint of the flue, reduce leakage points and unnecessary ancillary facilities, and simplify the anti-corrosion system.

[0005] The flange surface compression seal strip is rectangular, with a total length equal to the circumference of the flue expansion joint flange surface, a width equal to the width of the flange, and a thickness of 5-8 mm, depending on the strength of the material (such as aluminum alloy or polymer material strips). The higher the strength, the thinner the thickness. The lower the strength, the thicker the thickness. In short, the thickness should be sufficient to ensure that the strip does not deform during use and exerts a lasting and uniform pressure on the flange sealing surface. The strip should have bolt holes corresponding to the flange surface for bolting during installation.

[0006] Technical Solution 1: A flexible expansion joint for a desulfurization flue system, the flange sealing surface of the flexible expansion joint adopts a double sealing structure of an adhesive and a compression sealing strip.

[0007] Technical Solution 2: An on-site installation method for a flexible expansion joint for a desulfurization flue system, wherein the flange surface of the flue expansion joint is cleaned and polished to remove dirt and rust from the surface, and then adhesive is applied, a polymer flexible plate is installed, and a clamping strip is added and fastened with bolts.

[0008] Compared with the background technology, the desulfurization flue expansion joint manufactured by the present invention has a reliable sealing structure, simple installation and operation, flexibility and low price. It not only has excellent chemical medium resistance, anti-aging performance and effective resistance and absorption of stress or displacement caused by mechanical vibration, and its service life meets the requirements of design specifications, but also can be used for the configuration of newly built desulfurization flue system devices, and is more suitable for the rapid maintenance or replacement of old expansion joints. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Schematic diagram of a flexible expansion joint.

[0010] Figure 2 Schematic diagram of compression sealing strip.

[0011] Figure 3 Schematic diagram of the support plate.

[0012] Figure 4 Schematic diagram of the desulfurization flue system. DETAILED DESCRIPTION

[0013] Embodiment 1: refer to the attached Figure 1-3 A flexible expansion joint for a flue gas desulfurization system, the flange sealing surface of the flexible expansion joint adopts a double sealing structure of an adhesive 1 and a compression seal strip 2. The compression seal strip is rectangular, with a total length equal to the circumference of the flue gas expansion joint flange surface, a width equal to the width of the flange, and a thickness of 5-8 mm. The pressure strip is provided with bolt holes 3 corresponding to the flange surface for bolt tightening during installation. The flange surface compression seal strip in the flexible expansion joint adopts a polymer flexible plate.

[0014] Embodiment 2: Based on Embodiment 1, the flexible expansion joint is provided with a support plate 4. The support plate is an L-shaped support plate with a thickness of 3-5 mm. The short side of the L-shaped support plate, i.e., the flange sealing surface, is provided with bolt holes 3 corresponding to the flue flange surface, and the width thereof is equal to the width of the connected flange surface. The long side width of the L-shaped support plate is 200 mm. The diameter of the bolt hole on the L-shaped support plate is 3 mm larger than the bolt hole on the flue flange surface, so as to adjust the overlap and installation of the support plate.

[0015] Example 3: Based on the above example, an on-site installation method for a flexible expansion joint for a desulfurization flue system is provided. The flange surface of the flue expansion joint is cleaned and polished to remove dirt and rust from the surface. Then, adhesive is applied, a polymer flexible plate is installed, and a compression strip is added and fastened with bolts.

[0016] Example 4: Based on Example 3, the flange surface of the flue expansion joint is cleaned and polished to remove dirt and rust from the surface, and then the adhesive is applied, the polymer flexible plate and the support plate are installed, and the clamping strip is installed and fastened with bolts.

[0017] Example 5 Clean flue directly sticks the polymer composite board to the inner surface of the flue expansion joint. The method is: clean and polish the surface to be bonded to make it free of dirt and rust, then apply adhesive and stick the polymer composite board. The width of the bonding surface is 100 to 200 mm.

[0018] For the convenience of management and quality control, the standardized production and transportation of support plates and compression strips are an important link, and their length is uniformly set to 1 meter. The desulfurization flue expansion joint made by this technical solution has a reliable sealing structure, simple installation and operation, flexible and low price, and has excellent chemical medium resistance, anti-aging performance, and effective resistance and absorption of stress or displacement caused by mechanical vibration. The service life meets the requirements of the design specifications. It can be used for the configuration of new desulfurization flue system devices, and is more suitable for the rapid repair or replacement of old expansion joints.

[0019] It should be understood that although the above embodiments provide a relatively detailed textual description of the design ideas of the present invention, these textual descriptions are only simple textual descriptions of the design ideas of the present invention, rather than limitations on the design ideas of the present invention. Any combination, addition or modification that does not exceed the design ideas of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for on-site installation of a flexible expansion joint for a desulfurization flue system, characterized by: The flange surface compression seal strip in the flexible expansion joint adopts a polymer flexible plate. The flange sealing surface of the flexible expansion joint adopts a double sealing structure of an adhesive (1) and a compression seal strip (2). The flange surface compression seal strip is rectangular, and its total length is equal to the circumference of the flange surface of the flexible expansion joint, its width is equal to the width of the flange, and its thickness is 5-8 mm, which varies depending on the strength of the material, and is sufficient to ensure that the compression seal strip does not deform during use and exerts a lasting and uniform pressure on the flange sealing surface. The flexible expansion joint is provided with a support plate (4), and the support plate is an L-shaped support plate with a thickness of 3-5 mm. The short side of the L-shaped support plate is provided with bolt holes (3) corresponding to the flue flange surface, and the width of the bolt holes is equal to the width of the connected flange surface; the clean flue directly adheres the polymer composite plate to the inner surface of the flexible expansion joint, and the installation method is: the surface to be bonded is cleaned and polished to make the surface free of dirt and rust, and then the adhesive is applied, and the polymer composite plate is bonded, the width of the bonding surface is 100-200 mm, and a compression sealing strip is installed and fastened with bolts. The compression sealing strip is rectangular, and its total length is equal to the circumference of the flexible expansion joint flange surface, the width is equal to the width of the flange, and the thickness is 5-8 mm. The compression sealing strip is provided with bolt holes (3) corresponding to the flange surface, so that the bolts can be fastened during installation.

2. The on-site installation method of the flexible expansion joint for the desulfurization flue system according to claim 1 is characterized by: The long side width of the L-shaped support plate is 200mm.

3. The on-site installation method of the flexible expansion joint for the desulfurization flue system according to claim 1 is characterized by: The diameter of the bolt holes on the L-shaped support plate is 3mm larger than the bolt holes on the flue flange surface to facilitate the adjustment of the overlap and installation of the support plate.

4. The on-site installation method of the flexible expansion joint for the desulfurization flue system according to claim 1 is characterized by: Clean and polish the flange surface of the flexible expansion joint to make it free of dirt and rust, then apply adhesive, install the polymer flexible plate and support bracket, add the compression sealing strip and tighten it with bolts.

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