Processing technology of boiler water wall tube

Abstract

The invention relates to the technical field of cold wall tubes, in particular to a boiler water wall tube machining process which comprises the following steps: detecting the surface of a boiler water wall, then cleaning dirt and dust on the surface, mounting the boiler water wall on laser cladding equipment or automatic arc surfacing equipment, then carrying out cladding surfacing bottoming, and detecting the surface of the boiler water wall tube again after bottoming is completed. Uniform bottoming of the surface of the boiler water wall tube is ensured; silicon carbide plastic cement is prepared, and finally the plastic cement is smeared; by means of the operation, the pipes do not need to be replaced frequently during later maintenance and replacement, the maintenance cost of the boiler is reduced, the service life of the water wall pipe of the boiler is prolonged by two years to ten years, and the use cost is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of cold wall tubes, and in particular to a processing technology for boiler water-cooled wall tubes. Background Art

[0002] The boiler water-cooled wall tube is the main heat-receiving part of the boiler, which is composed of several rows of steel pipes distributed around the boiler furnace. Water or steam flows inside the water-cooled wall tube, and the outside receives the flame heat from the boiler furnace; the water-cooled wall tube is usually made of seamless steel pipes with a diameter of φ=51-60mm, the material is 20# steel, and the wall thickness is 3-5mm. The most widely used in small and medium-sized boilers is the bare tube water-cooled wall, which is generally close to the four walls of the furnace, arranged vertically and parallel to each other, connected to the boiler drum or upper header at the top, and connected to the lower header at the bottom. In large-capacity boilers, membrane water-cooled walls are more commonly used, which are welded from bare tubes and fins;

[0003] The water-cooled wall tubes have the functions of cooling and protecting the furnace wall. Through radiation heat transfer, the working fluid in the water-cooled wall absorbs heat and gradually changes from water to a steam-water mixture, completing the evaporation of the working fluid. By absorbing a large amount of heat from high-temperature flue gas, the flue gas temperature near the furnace wall and at the furnace outlet is reduced to below the softening temperature of the ash, preventing slagging on the furnace wall and the heating surface, improving the safety and reliability of boiler operation, and simplifying the furnace wall structure to create conditions for the use of light furnace walls and save metal.

[0004] Most of the existing boiler water-cooled wall tubes do not have the properties of corrosion resistance and wear resistance. As a result, after long-term use, the surface of the boiler water-cooled wall tubes will be damaged, and frequent maintenance is required, which is not only time-consuming and labor-intensive, but also greatly increases the maintenance cost.

[0005] Therefore, those skilled in the art provide a boiler water-cooled wall tube to solve the problems raised in the above background technology. Summary of the invention

[0006] In order to solve the above technical problems, based on the experience accumulated from many years of repair of various boiler water-cooled wall tubes, the present invention provides a boiler water-cooled wall tube processing technology to reduce the maintenance cost of boiler water-cooled wall tubes and improve production efficiency. The specific operation steps are as follows;

[0007] S1. Check the surface of boiler water-cooling tubes: Place the boiler water-cooling wall tubes to be used on the workbench, and then use the detection device to detect whether there are defects on the surface of the boiler water-cooling wall tubes, as well as whether there is dust and other dirt, to determine the thickness of the tube wall and necessary parameters, so as to proceed to the next step;

[0008] S2. Clean the dust on the surface of boiler water-cooled wall tubes and keep the boiler water-cooled wall tubes clean and tidy;

[0009] S3. Equipment installation: Install laser cladding equipment or automatic arc cladding equipment;

[0010] S4. Actual operation: perform cladding and welding primer;

[0011] S5. Re-check: After the fusion welding is completed, check to ensure that the surface of the fusion welding layer must be uniform and flat;

[0012] S6, configure silicon carbide plastic;

[0013] S7, brush the surface with plastic glue.

[0014] Preferably, in step S3: a clamping mechanism is installed on the workbench, the clamping mechanism is arranged at both ends of the boiler water-cooled wall tube; and a motor 1 is provided on the clamping mechanism; a laser cladding equipment or an automatic arc cladding equipment is installed on the upper side of the workbench; and the laser cladding equipment or the automatic arc cladding equipment is located above the boiler water-cooled wall tube; a screw is provided at the bottom of the laser cladding equipment or the automatic arc cladding equipment, and a motor 2 is provided on the screw, and the laser cladding equipment or the automatic arc cladding equipment is debugged after installation.

[0015] Preferably, in step S4: the boiler water-cooled wall tube is clamped and stabilized by a clamping mechanism, and then motor one is started to drive the entire boiler water-cooled wall tube to rotate, and then motor two is started to drive the screw at the bottom of the laser cladding equipment or the arc automatic cladding equipment to move, and then the laser cladding equipment or the arc automatic cladding equipment is driven to move left and right, and then the laser cladding equipment or the arc automatic cladding equipment is started to perform cladding and cladding welding on the boiler water-cooled wall tube at different positions; the boiler water-cooled wall tube rotates during fusion welding to ensure uniform fusion welding; then a layer of nickel-based alloy material with a thickness of 0.5 mm to 2.5 mm is clad on the surface of the boiler water-cooled wall tube by a machine; in corners that the machine cannot cover, manual two-protection fusion welding operation is adopted.

[0016] Preferably, in step S6: the silicon carbide plastic is composed of 2000 mesh silicon carbide powder (15%-35%) + sodium fluorosilicate (1.5%-3%) + binder water glass (62%-83.5%).

[0017] Preferably, in step S7: when brushing the plastic glue on the surface, start motor 1 to drive the boiler water-cooled wall tube to rotate, and use a brush to evenly apply the glue on the surface of the boiler water-cooled wall tube during rotation, and the thickness of the glue is 0.2mm-1mm.

[0018] Preferably, when brushing the plastic glue, the glue can be applied by manually controlling the brush or by using a machine-controlled brush, that is, manually brushing the glue or machine brushing the glue.

[0019] Technical effects and advantages of the present invention:

[0020] 1. The present invention provides a boiler water-cooled wall tube, which has the function of anti-corrosion and anti-wear, and directly clads a layer of 0.5mm to 2.5mm thick wear-resistant wire on the outside of the tube with a laser; or manually welds a layer of 0.5mm to 2.5mm thick wear-resistant wire, and then coats a layer of 0.2 to 50mm thick silicon carbide plastic, so there is no need to frequently replace the tube, reduce the cost of boiler maintenance, and extend the service life of the boiler water-cooled wall tube by two to ten years.

[0021] 2. The present invention uses a clamping mechanism on a workbench to clamp the boiler water-cooled wall tubes, thereby preventing the boiler water-cooled wall tubes from moving later; it is also convenient to clamp water-cooled wall tubes of different sizes.

[0022] 3. The present invention starts motor 2 to drive the screw at the bottom of the laser cladding equipment or the automatic arc cladding equipment to move, thereby driving the laser cladding equipment or the automatic arc cladding equipment to move left and right, and then starts the laser cladding equipment or the automatic arc cladding equipment to perform cladding and cladding welding on the boiler water-cooled wall tubes at different positions; the boiler water-cooled wall tubes rotate during fusion welding to ensure uniform fusion welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a process flow chart of a boiler water-cooled wall tube processing provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0025] Example

[0026] See also Figure 1 In this embodiment, a processing technology for a boiler water-cooled wall tube is provided, comprising the following steps:

[0027] 1. Place the boiler water-cooled wall tubes to be used on the workbench, and then use the detection device to detect whether there are defects on the surface of the boiler water-cooled wall tubes, as well as whether there is dust and other dirt, to determine the thickness of the tube wall and other necessary parameters, so as to proceed to the next step;

[0028] 2. There is dust on the surface of the boiler water-cooled wall tube. Please use a brush to remove the dirt on the surface of the boiler water-cooled wall tube. After cleaning, keep the boiler water-cooled wall tube clean and tidy;

[0029] 3. Install the equipment. Install a clamping mechanism on the workbench. The clamping mechanism is located at both ends of the boiler water-cooled wall tube. It is used to clamp the boiler water-cooled wall tube to prevent the boiler water-cooled wall tube from moving later. A motor 1 is provided on the clamping mechanism. Then a laser cladding device or an arc automatic cladding device is installed on the upper side of the workbench. The laser cladding device or the arc automatic cladding device is located above the boiler water-cooled wall tube. After installation, the laser cladding device or the arc automatic cladding device is debugged to facilitate the cladding and cladding of the boiler water-cooled wall tube in the later stage. A screw is provided at the bottom of the laser cladding device or the arc automatic cladding device, and a motor 2 is provided on the screw.

[0030] 4. Actual operation: Clamp and stabilize the boiler water-cooled wall tube through the clamping mechanism, then start motor 1 to drive the entire boiler water-cooled wall tube to rotate, then start motor 2 to drive the screw at the bottom of the laser cladding equipment or the arc automatic cladding equipment to move left and right, and then start the laser cladding equipment or the arc automatic cladding equipment to perform cladding and cladding on the boiler water-cooled wall tube at different positions; the boiler water-cooled wall tube rotates during fusion welding to ensure uniform fusion welding; then use the machine to clad the surface of the boiler water-cooled wall tube with a layer of nickel-based alloy material with a thickness of 0.5mm to 2.5mm; in corners that the machine cannot cover, use manual fusion welding operation;

[0031] 5. Check again. After the fusion welding is completed, inspect the water-cooled wall tubes after fusion welding to ensure that the surface of the fusion welding layer must be uniform and flat;

[0032] 6. Prepare silicon carbide plastic, 2000 mesh silicon carbide powder (15%-35%) + sodium fluorosilicate (1.5%-3%) + binder water glass (62%-83.5%);

[0033] 7. Brush the plastic glue on the surface. Start the motor 1, which drives the clamping mechanism to rotate, and then drives the boiler water-cooled wall tube on the clamping mechanism to rotate. During the rotation, manually control the brush to evenly apply the glue on the surface of the boiler water-cooled wall tube, and the thickness of the glue is 0.2mm-1mm. Manual glue brushing is not accurate enough and will cause waste of glue. Machine glue brushing can be used to ensure that the thickness of the glue is within a fixed range.

[0034] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A boiler water-cooled wall tube processing technology, characterized in that: The method comprises the following steps: S1. Check the surface of boiler water-cooling tubes: Place the boiler water-cooling wall tubes to be used on the workbench, and then use the detection device to detect whether there are defects on the surface of the boiler water-cooling wall tubes, as well as whether there is dust and other dirt, to determine the thickness of the tube wall and necessary parameters, so as to proceed to the next step; S2. Clean the dust on the surface of boiler water-cooled wall tubes and keep the boiler water-cooled wall tubes clean and tidy; S3. Equipment installation: Install laser cladding equipment or automatic arc cladding equipment; S4. Actual operation: perform cladding and welding primer; S5. Re-check: After the fusion welding is completed, check to ensure that the surface of the fusion welding layer must be uniform and flat; S6, configure silicon carbide plastic; S7, brush the surface with plastic glue.

2. A boiler water wall tube processing technology according to claim 1, characterized in that: In the step S3: a clamping mechanism is installed on the workbench, the clamping mechanism is arranged at both ends of the boiler water-cooled wall tube; and a motor 1 is arranged on the clamping mechanism; a laser cladding device or an automatic arc cladding device is installed on the upper side of the workbench; and the laser cladding device or the automatic arc cladding device is located above the boiler water-cooled wall tube; a screw rod is arranged at the bottom of the laser cladding device or the automatic arc cladding device, and a motor 2 is arranged on the screw rod, and after installation, the laser cladding device or the automatic arc cladding device is debugged.

3. A boiler water-cooled wall tube processing process according to claim 1 or 2, characterized in that: In the step S4: the boiler water-cooled wall tube is clamped and stabilized by a clamping mechanism, and then the motor 1 is started to drive the entire boiler water-cooled wall tube to rotate, and then the motor 2 is started to drive the screw at the bottom of the laser cladding equipment or the arc automatic cladding equipment to move, and then the laser cladding equipment or the arc automatic cladding equipment is driven to move left and right, and then the laser cladding equipment or the arc automatic cladding equipment is started to perform cladding and cladding welding on the boiler water-cooled wall tube at different positions; the boiler water-cooled wall tube rotates during fusion welding to ensure uniform fusion welding; then a layer of nickel-based alloy material with a thickness of 0.5 mm to 2.5 mm is clad on the surface of the boiler water-cooled wall tube by a machine; in corners that are not covered by the machine, manual fusion welding operation is adopted.

4. A boiler water wall tube processing technology according to claim 1, characterized in that: In the step S6, the silicon carbide plastic is composed of 2000 mesh silicon carbide powder (15%-35%) + sodium fluorosilicate (1.5%-3%) + binder water glass (62%-83.5%).

5. The boiler water wall tube processing technology according to claim 1 is characterized in that: In the step S7, when brushing the plastic glue on the surface, the motor 1 is started to drive the boiler water-cooled wall tube to rotate, and the glue is evenly applied to the surface of the boiler water-cooled wall tube with a brush during rotation, and the thickness of the glue is 0.2mm-1mm.

6. A boiler water wall tube processing technology according to claim 5, characterized in that: When applying the plastic glue, the glue can be applied by manually controlling the brush or by using a machine-controlled brush, that is, manually applying the glue or by using a machine.

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