A compartmentalized coal hopper and a welding method thereof

Abstract

The present application relates to the field of thermal power engineering, and discloses a kind of warehouse coal bucket and welding method thereof, warehouse coal bucket includes warehouse body and warehouse board, the inner wall of storage section of warehouse body is welded with the side of warehouse board body towards the inner stiffening rib profile steel of warehouse board, the stainless steel coating of the other side of the inner wall of storage section and the body is welded and fixed by transition electrode, the inner wall of warehouse body blanking section is provided with stainless steel coating, the inner wall of blanking section close to the front and rear ends of each inner stiffening rib profile steel is welded and fixed with the two ends of each inner stiffening rib profile steel after scraping off stainless steel coating, the inner wall of blanking section and the side of the body towards the inner stiffening rib profile steel are welded by transition electrode, the stainless steel coating of the other side of the inner wall of storage section and the body is welded and fixed, the strength and durability of welded joint are ensured, the service life of warehouse coal bucket is effectively prolonged, and the safety hazard caused by welding connection failure due to bimetallic corrosion is significantly reduced.

Description

Technical Field

[0001] This invention belongs to the field of thermal power engineering technology, and in particular relates to a coal hopper in a coal conveying system of a thermal power plant and its welding method. Background Technology

[0002] The power industry is a fundamental industry and public utility for national economic and social development, and power plants are the places where electrical energy is generated. In my country, thermal power generation has advantages such as low site selection requirements, short construction period, strong power generation stability, low power generation cost and low grid connection price. In addition, my country has abundant coal resources, and thermal power generation has always dominated the power industry. The coal hopper is a key part of the fuel storage and transportation system of a thermal power plant. After being crushed by a coal crusher, the coal is transported by belt conveyor to the coal bunker, temporarily stored in the coal hopper, and then fed by a coal feeder to the coal mill for grinding into powder, and finally sent to the boiler burner.

[0003] Coal hoppers can be classified into reinforced concrete and steel structures, and into circular and square shapes. Circular steel coal hoppers are most commonly used in thermal power plants. Circular steel coal hoppers typically consist of a straight upper section and a conical lower section. The straight section stores most of the coal, while the conical section facilitates its discharge. The side walls are generally made of rolled and welded steel plates. To improve structural strength, circumferential angle steel or channel steel is added as stiffening ribs on the outside. Because the conical section needs to withstand significant coal friction, current technology improves the wear resistance of the conical section by welding a stainless steel lining to the inner wall. However, the traditional welding between carbon steel or low-alloy steel walls and the stainless steel lining carries the risk of bimetallic corrosion, which not only reduces the service life of the coal hopper but may also threaten the operational safety of the thermal power plant. In 2022, my country implemented the mandatory standard "General Specification for Steel Structures," which explicitly stipulates that stainless steel components should not be welded to carbon steel or low-alloy steel components.

[0004] With the changing structure of my country's coal resource supply, blending non-designed coal types in large proportions has become the norm for coal-fired power generating units. In order to achieve precise fuel blending and improve the economic, safety, and environmental characteristics of unit operation, the design of coal hoppers into compartments has become the choice of some power plants. By designing coal hoppers into compartments, not only can the switching of coal types be maximized and made more flexible, but the needs of storage and transportation of different coal types can also be met.

[0005] In the existing technology, the compartmented coal hopper adopts a steel pipe external rib type compartment plate. The plate body of the steel pipe external rib type compartment plate is made of stainless steel composite plate. Semi-circular tubes are symmetrically welded on both sides of the plate body as external stiffening ribs. After the compartment plate is constructed, it is welded into the interior of the coal hopper as a whole. The split external rib is made of carbon steel or low alloy steel components. The welding between the split external rib and the split compartment plate body, the welding between the split external rib and the conical section of the coal hopper, and the welding between the plate body and the side wall of the straight section of the coal hopper constitute direct welding between stainless steel components and carbon steel or low alloy steel components.

[0006] In the existing technology, the welding between the split plates and the hopper body of the split coal hopper is a direct welding of stainless steel components to carbon steel or low alloy steel components. Long-term operation of bimetallic welding will gradually corrode the connection position, affect the connection strength, and pose certain safety hazards. It cannot meet the requirements of the current standard "General Specification for Steel Structures". Summary of the Invention

[0007] The technical problem to be solved by the present invention is that the welding between the split plate and the hopper body in the prior art split coal hopper is a direct welding of stainless steel components and carbon steel or low alloy steel components. Long-term operation of bimetallic welding will gradually corrode the connection position, affect the connection strength, and pose certain safety hazards.

[0008] In view of the above problems, the present invention proposes a compartmented coal hopper, which includes a hopper body and a compartment plate. The hopper body includes a storage section and a discharge section that are connected vertically. The compartment plate is vertically arranged in the hopper body and extends from the storage section to the bottom of the discharge section. The compartment plate is characterized in that: the compartment plate includes a number of vertically arranged internal stiffening ribs and plates welded to the left and right sides of the internal stiffening ribs. The web of each internal stiffening rib is placed horizontally.

[0009] The material of each internal stiffening rib is carbon steel or low alloy high strength steel. The material of the side of each plate facing the internal stiffening rib is carbon steel or low alloy high strength steel, and the other side of each plate is provided with a stainless steel cladding.

[0010] The inner wall of the storage section is welded and fixed to both ends of each internal stiffening rib steel, the inner wall of the storage section is welded to the side of the plate facing the internal stiffening rib steel, and the inner wall of the storage section is welded and fixed to the stainless steel cladding of the plate by transition welding rods.

[0011] The inner wall of the blanking section is covered with a stainless steel coating. The stainless steel coating on the inner wall of the blanking section near the front and rear ends of each internal stiffening rib is scraped off so that it can be welded and fixed to the ends of each internal stiffening rib.

[0012] The inner wall of the unloading section is welded to one side of the plate with inward stiffening ribs using transition welding rods, and the inner wall of the storage section is welded to the stainless steel cladding on the other side of the plate.

[0013] Preferably, the sidewall of the material dropping section is made of stainless steel composite plate; the plate body is made of stainless steel composite plate.

[0014] Each stainless steel composite plate is made by directly rolling the base layer and the cladding layer. The base layer is made of carbon steel or low alloy high strength steel, and the cladding layer is made of stainless steel.

[0015] Preferably, each internal stiffening rib is an I-beam or an H-beam.

[0016] Preferably, stiffening plates are arranged in a ring shape on the outer sidewalls of the storage section and the unloading section, corresponding to the relative positions of the internal stiffening ribs.

[0017] Preferably, the thickness of the lower sidewall of the storage section is greater than the thickness of the upper sidewall of the storage section, so that the lower sidewall of the storage section forms a thickened plate, the inner surface of the thickened plate is flush with the inner surface of the upper cylinder wall, and the material discharge section is welded and fixed to the thickened plate.

[0018] This invention also proposes a welding method for subdivided coal hoppers, the steps of which are as follows:

[0019] S1. Prefabricate the storage section and the unloading section of the silo body separately, and weld the top of the unloading section to the storage section for fixation;

[0020] S2. Weld the two ends of each internal stiffening rib steel to the inner wall of the storage section and the unloading section respectively. Before welding, scrape off the stainless steel coating of the part to be welded in the unloading section.

[0021] S3. Weld and fix one side of each plate to the internal stiffening rib steel.

[0022] S4. Weld the inner wall of the storage section to one side of the plate facing the inward stiffening ribs and fix it to the stainless steel cladding on the other side of the plate by welding with transition welding rods.

[0023] S5. The inner wall of the blanking section is welded to one side of the plate facing the inward stiffening ribs by a transition welding rod, and the inner wall of the blanking section is welded to the stainless steel cladding on the other side of the plate.

[0024] Preferably, in step S1, the storage section and the unloading section of the silo are prefabricated respectively, and the top of the unloading section is welded and fixed to the storage section.

[0025] The stainless steel cladding on the inner wall of the blanking section is welded using transition welding rods, forming a transition weld after welding. Ordinary welds are formed by welding the inner wall of the blanking section and the inner wall of the storage section using welding rods that are compatible with carbon steel or low alloy high strength steel.

[0026] Preferably, in step S3, welding and fixing one side of each plate from carbon steel or low-alloy high-strength steel to the internal stiffening rib steel specifically involves:

[0027] One side of each plate is made of carbon steel or low-alloy high-strength steel and is covered on both sides of the internal stiffening rib. Then, the plate on one side of the stiffening rib is welded. Then, the other side of the plate is cut into bevels according to the spacing of each internal stiffening rib. The bevels expose the stainless steel cladding. The inner wall of the blanking section and the inner wall of the storage section are welded with welding rods that match the carbon steel or low-alloy high-strength steel to form a normal weld. The transition weld is performed with transition welding rods that match the stainless steel cladding. The stainless steel weld is performed with stainless steel cladding welding rods.

[0028] Preferably, in step S4, the inner wall of the storage section is welded and fixed to the side of the plate facing the inward stiffening rib, and the stainless steel cladding on the other side of the plate is welded and fixed using transition welding rods. Specifically:

[0029] Ordinary welds are welded using electrodes that match carbon steel or low-alloy high-strength steel, and transition welds are welded using transition electrodes that match the stainless steel cladding. The top surface of the transition weld is flush with the outer surface of the stainless steel cladding.

[0030] Preferably, in step S5, the inner wall of the blanking section is welded to one side of the plate facing the inward stiffening rib using a transition welding rod, and the inner wall of the blanking section is welded and fixed to the stainless steel cladding on the other side of the plate. Specifically, this is done as follows:

[0031] Transition welds are performed using transition electrodes that match the stainless steel cladding, while stainless steel welds are performed using stainless steel cladding electrodes.

[0032] Compared with the prior art, the beneficial effects of the coal hopper with compartmentation and its welding method according to the present invention are as follows:

[0033] In traditional coal hoppers, different metals are directly welded together in different parts, making the metal with the higher potential the positive electrode (cathode) and the metal with the lower potential the negative electrode (anode). In humid, oxygen-rich, or corrosive environments (such as coal dust, moisture, etc.), the negative electrode metal undergoes an oxidation reaction, which is called anodic corrosion.

[0034] In this application, the inner wall of the storage section is welded to both ends of each internal stiffening rib, the inner wall of the storage section is welded to the side of the plate facing the internal stiffening rib, and the inner wall of the storage section is welded to the stainless steel cladding of the plate by transition welding rods.

[0035] The inner wall of the blanking section is covered with a stainless steel coating. The stainless steel coating on the inner wall of the blanking section near the front and rear ends of each internal stiffening rib is scraped off so that it can be welded and fixed to the ends of each internal stiffening rib.

[0036] The inner wall of the material dropping section is welded to the side of the inward-facing stiffening ribs of the plate using transition welding rods. The inner wall of the material dropping section is welded to the stainless steel cladding on the other side of the plate. This allows for direct welding of different components of the coal hopper made of the same material. For welding between components made of different materials, methods such as scraping off the stainless steel cladding or using transition welding rods are employed. This avoids the problem of electrochemical corrosion that easily occurs when directly welding different metal materials in traditional coal hoppers, which leads to a decrease in the strength of the welded joint. This ensures the strength and durability of the welded joint, effectively extends the service life of the coal hopper, and significantly reduces the safety hazards caused by weld failure due to bimetallic corrosion. Attached Figure Description

[0037] Figure 1 This is a top view of the coal hopper in an embodiment of the present invention;

[0038] Figure 2 This is an elevation sectional view of the coal hopper in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the compartment plate structure of the compartment coal hopper according to an embodiment of the present invention;

[0040] Figure 4 yes Figure 3 Enlarged view of point A in the middle;

[0041] Figure 5 This is a schematic diagram of the stiffening plate and horizontal weld seam of the storage section of the coal hopper in an embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the vertical weld seam on the side wall of the storage section of the coal hopper in an embodiment of the present invention;

[0043] Figure 7 This is a schematic diagram of the vertical weld seam on the side wall of the thickened plate at the bottom of the storage section of the coal hopper in an embodiment of the present invention;

[0044] Figure 8 This is a schematic diagram of the peripheral structure of the thickened plate at the bottom of the storage section of the coal hopper in an embodiment of the present invention;

[0045] Figure 9 yes Figure 8 Sectional view along line AA;

[0046] Figure 10 yes Figure 9 Sectional view along the BB direction;

[0047] Figure 11 This is a schematic diagram of the horizontal weld seam on the side wall of the material dropping section of the coal hopper in an embodiment of the present invention;

[0048] Figure 12 This is a schematic diagram of the vertical weld seam on the side wall of the material dropping section of the coal hopper in an embodiment of the present invention;

[0049] Figure 13 This is a schematic diagram of the stiffening plate of the material discharge section of the coal hopper in an embodiment of the present invention;

[0050] Figure 14 This is a schematic diagram of the connection structure between the storage section and the discharge section of the coal hopper in an embodiment of the present invention;

[0051] Figure 15 This is a schematic diagram of the connection structure between the stiffening ribs inside the compartment plate and the inner wall of the storage section in an embodiment of the present invention;

[0052] Figure 16 This is a schematic diagram of the connection structure between the stiffening ribs in the compartment plate and the inner wall of the material dropping section in an embodiment of the present invention;

[0053] Figure 17 This is a schematic diagram of the connection structure between the stiffening ribs and the plate body in an embodiment of the present invention;

[0054] Figure 18 yes Figure 17 Enlarged view of point A in the middle;

[0055] Figure 19 This is a schematic diagram of the connection structure between the compartment plate and the inner wall of the storage section in an embodiment of the present invention;

[0056] Figure 20 This is a schematic diagram of the connection structure between the compartment plate and the inner wall of the material dropping section in an embodiment of the present invention.

[0057] In the diagram, 1. Container body; 2. Compartment plate; 3. Storage section; 4. Unloading section; 5. Internal stiffening ribs; 6. Plate; 7. Stiffening plate; 8. Thickened plate; 10. Annular bottom plate; 11. Circumferential horizontal stiffening plate; 12. Rectangular vertical stiffening plate; 13. Trapezoidal vertical stiffening plate; 14. Triangular fall arrest support plate; 15. Bolt hole; 16. Connecting angle steel; 100. Ordinary weld; 200. Transition weld; 300. Stainless steel weld. Detailed Implementation

[0058] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0059] In the description of this invention, it should be understood that the term "transition electrode" is used here. A transition electrode is a special type of welding electrode that has undergone special processing and is suitable for welding various metals. The main function of a transition electrode is to connect metal electrodes made of different materials. Since there are significant differences in the chemical composition and physical properties (such as coefficient of thermal expansion and thermal conductivity) between metal electrodes made of different materials, using a transition electrode can act as a buffer, reducing welding problems caused by differences in chemical composition and physical properties, resulting in a more uniform and aesthetically pleasing weld, while ensuring the quality and reliability of the weld joint.

[0060] like Figure 1 and Figure 2 As shown in the preferred embodiment of the present invention, a compartmented coal hopper includes a hopper body 1 and a compartment plate 2. The hopper body 1 includes a storage section 3 and a discharge section 4 that are connected vertically. The compartment plate 2 is vertically arranged inside the hopper body 1 and extends from the storage section 3 to the bottom of the discharge section 4. The compartment plate 2 divides the inner cavity of the hopper body 1 into two parts, thereby maximizing the flexibility and adaptability of coal type switching.

[0061] like Figure 3 and Figure 4 As shown, the compartment plate 2 includes several vertically arranged internal stiffening ribs 5 and plates 6 welded to the left and right sides of the internal stiffening ribs 5. The webs of each internal stiffening rib 5 are placed horizontally.

[0062] Each internal stiffening rib 5 is made of carbon steel Q235 or low-alloy high-strength steel Q355. The side of each plate 6 facing the internal stiffening rib 5 is also made of carbon steel Q355 or low-alloy high-strength steel Q355. The thickness of each plate 6 is generally 10mm to 12mm. By welding the parts of the plate 6 and the internal stiffening rib 5 that are made of the same material, bimetallic welding is avoided when the plate 6 and the internal stiffening rib 5 are welded together.

[0063] Each plate 6 has a stainless steel cladding on its other side, which is typically 3mm thick. Specifically, the plate 6 is made of stainless steel composite plate. The base material of the stainless steel composite plate is carbon steel Q235 or low-alloy high-strength steel Q355, and the base plate thickness is typically 10mm to 12mm. The cladding material is stainless steel, and the cladding plate thickness is typically 3mm.

[0064] When the compartment plate 2 is added, the height-to-width ratio of each compartment of the silo body 1 is doubled compared to the original silo body 1. The side walls of each compartment will be subjected to a significant increase in lateral extrusion pressure from the coal stored inside. Therefore, the compartment plate 2 will bear a large load. By setting a stainless steel coating on the side of the plate 6 facing the silo body 1, the wear resistance of the plate 6 can be improved, and the service life of the compartment plate 2 can be increased.

[0065] like Figure 15 and Figure 19 As shown, the inner wall of storage section 3 is welded to both ends of each inner stiffening rib steel 5, and the inner wall of storage section 3 is welded to the side of plate 6 facing the inner stiffening rib steel 5, that is, the side of storage section 3 with the same material as plate 6 is directly welded; the inner wall of storage section 3 is welded to the stainless steel cladding on the other side of plate 6 using transition welding rods. Through the special design of the welding points—namely, the direct welding of the inner wall of storage section 3 to the inner stiffening rib steel 5 and the side with the same material as plate 6, and the welding fixation to the stainless steel cladding on the other side of plate 6 using transition welding rods—the problems caused by bimetallic welding are effectively avoided, thereby ensuring the strength and stability of the welding points and improving the reliability and durability of the entire storage structure.

[0066] The inner wall of the material dropping section 4 is covered with a stainless steel coating. By setting the stainless steel coating on the inner wall of the material dropping section 4, the wear resistance of the material dropping section is significantly improved and the service life of the material dropping section 4 is extended.

[0067] like Figure 16 and Figure 20 As shown, after scraping off the stainless steel cladding layer from the inner wall of the blanking section 4 near both ends of each inner stiffening rib steel 5, it is welded and fixed to both ends of each inner stiffening rib steel 5. The inner wall of the blanking section 4 is welded to the side of the plate 6 facing the inner stiffening rib steel 5 using a transition welding rod; the inner wall of the blanking section 4 is welded and fixed to the stainless steel cladding layer on the other side of the plate 6, that is, the stainless steel cladding layers are directly welded to each other. By scraping off the stainless steel cladding layer of the blanking section 4 near the inner stiffening rib steel 5, direct welding and fixing to the inner stiffening rib steel 5 is achieved. At the same time, the inner wall of the blanking section 4 is welded to the same side of the plate 6 using a transition welding rod, avoiding the problem of direct bimetallic welding of stainless steel cladding layer to carbon steel or low alloy high-strength steel; while the stainless steel cladding layer on the other side of the plate 6 is directly welded to the blanking section 4, ensuring welding strength, improving the overall stability and reliability of the structure, and simplifying the welding process.

[0068] Specifically, each of the internal stiffening ribs 5 is an I-beam or an H-beam.

[0069] The webs of each I-beam or H-beam are parallel to the horizontal plane. The spacing between the flanges of each I-beam or H-beam is generally 200mm to 450mm, and the spacing between two adjacent vertical I-beams or H-beams is generally 600mm to 1000mm. This provides stable and uniform support for plate 6, effectively enhancing its resistance to deformation and ensuring its stability and reliability under significant lateral pressure.

[0070] like Figure 2As shown, preferably, stiffening plates 7 are arranged in a ring shape on the outer sidewalls of the storage section 3 and the unloading section 4, corresponding to the relative positions of each internal stiffening rib steel 5. By setting stiffening plates 7 on the outer wall of the silo body 1 corresponding to each internal stiffening rib steel 5, the structural strength of the silo body 1 is significantly enhanced, and the overall stability and load-bearing capacity of the silo body 1 are improved.

[0071] like Figure 5 As shown, specifically, the circumferential stiffening plate 7 of the side wall of storage section 3 is made of channel steel, and the positioning and spacing of the channel steel are consistent with the inner stiffening rib steel 5 of the compartment plate 2. The channel steel is bent according to the radius of the cylinder wall, with the flanges parallel to the horizontal plane and the openings facing the cylinder wall. The two flange plates are welded to the cylinder wall with single-sided fillet welds along their entire length.

[0072] like Figure 13 As shown, specifically, the circumferential stiffening plate 7 on the side wall of the material dropping section 4 is made of angle steel. The positioning and spacing of the angle steel are consistent with the inner stiffening ribs 5 of the compartment plate 2. The angle steel is bent according to the radius of the bucket wall, with the flanges parallel to the horizontal plane and the openings facing downwards. The flanges and the bucket wall are welded together with double-sided fillet welds along the entire length. Ribs are installed on the inner side of the angle steel at circumferential intervals of 500mm.

[0073] like Figures 8 to 10 As shown, the thickness of the lower sidewall of storage section 3 is greater than that of the upper sidewall, forming a thickened plate 8 on the lower sidewall of storage section 3. The thickened plate 8 is made of 30mm thick steel plate rolled and spliced ​​together. The vertical welds are double-sided bevel welds with a bevel gap of 2mm, a bottom thickness of 4mm, and an angle of 60°. The inner surface of the thickened plate 8 is flush with the inner surface of the upper cylinder wall. The connection between the outer surface of the thickened plate 8 and the outer surface of the upper cylinder wall has a smooth transition chamfer, specifically, the chamfer is 100mm high. The material dropping section 4 is welded and fixed to the thickened plate 8. By setting the thickened plate 8, the structural strength and durability of the lower part of storage section 3 are significantly enhanced. Moreover, by thickening the welding position between the bottom of storage section 3 and the material dropping section 4, stress concentration at the welding point is reduced, further improving the structural stability and service life of the entire silo 1.

[0074] The thickened plate 8 has an annular base plate 10 at its bottom, with bolt holes 15 pre-drilled on the annular base plate 10 according to the arrangement of the coal hopper support beams (the entire coal hopper has 8 supports, each with 3x2 pre-embedded bolts). A circumferential horizontal stiffening plate 11 is installed on the outer wall of the thickened plate 8 corresponding to the connection position of the material drop section. A rectangular vertical stiffening plate 12 is also installed on the outer wall of the thickened plate 8 between the annular base plate 10 and the circumferential horizontal stiffening plate 11. Simultaneously, a trapezoidal vertical stiffening plate 13 and a triangular anti-fall support plate 14 are installed at corresponding positions on the inner wall. By adding an annular base plate 10 at the bottom of the thickened plate 8 and pre-drilling bolt holes to cooperate with the coal hopper support beams, and by installing multiple reinforcing plates on the inner and outer walls of the thickened plate 8, the overall structural integrity, load-bearing capacity, and stability of the compartmented coal hopper are comprehensively improved, effectively preventing structural deformation and material falling risks, and ensuring the safe and reliable operation of the compartmented coal hopper.

[0075] The present invention also provides a welding method for a subdivided coal hopper, comprising the following steps:

[0076] S1. Prefabricate the storage section 3 and the material dropping section 4 of the silo body 1 respectively, and weld the top of the material dropping section 4 to the storage section 3.

[0077] Specifically, such as Figure 5 and Figure 6 As shown, the sidewall of storage section 3 is made of carbon steel Q235 or low alloy high strength steel Q355, with a plate thickness of generally 12mm. The steel plates are rolled into sections and then spliced ​​into straight cylinders. The horizontal welds are single-sided bevel welds with a bevel gap of 0mm, a bottom thickness of 2mm, and an angle of 45°. The vertical welds are single-sided bevel welds with a bevel gap of 2mm, a bottom thickness of 2mm, and an angle of 60°.

[0078] like Figure 11 and Figure 12 The base material of the sidewall of the blanking section 4 is carbon steel Q235 or low-alloy high-strength steel Q355, with a plate thickness of generally 10mm to 12mm. The inner wall of the blanking section 4 is also equipped with a stainless steel cladding, with a thickness of generally 3mm. The stainless steel cladding on the inner wall of the blanking section 4 significantly improves the wear resistance of the blanking section and extends its service life.

[0079] Specifically, the sidewall of the blanking section 4 is made of stainless steel composite plate rolled in sections. The base material of the stainless steel composite plate is carbon steel Q235 or low-alloy high-strength steel Q355, with a base plate thickness of generally 10mm to 12mm. The cladding material is stainless steel, with a cladding plate thickness of generally 3mm. After being rolled in sections, they are spliced ​​into a conical shape using double-sided bevel welding. The outer radius of the top of the blanking section is 2mm smaller than the inner radius of the storage section. Taking a base plate thickness of 12mm and a cladding thickness of 3mm as an example, the bevel gap between the stainless steel composite plates is 1mm ± 1mm. The bevel tip is on one side of the base plate, 3mm away from the interface between the base plate and the cladding. The bevel angles on both sides are 65° ± 5°. During welding, the base surface is first welded with welding material matching the base plate material to form a normal weld 100. The penetration depth of the normal weld 100 is controlled at a position 1.5mm to 2.5mm away from the interface between the base plate and the cladding. Then, a transition weld 200 is formed on the cladding side using a transition welding rod that matches the cladding material. The top surface of the transition weld 200 is controlled to be 0.5mm to 1.5mm higher than the interface between the base layer and the cladding. Finally, a cladding weld is formed using a cladding welding rod.

[0080] like Figure 14 As shown, after the prefabrication of storage section 3 and unloading section 4 is completed, storage section 3 is first hoisted onto the coal hopper support beam and fixed. Then, unloading section 4 is hoisted to the predetermined height. A transition weld 200 is formed by welding a local area at the junction of the base layer and the cover layer on the inner wall of unloading section 4 using transition welding rods. Then, ordinary weld 100 is formed by welding the inner wall of unloading section 4 and the inner wall of storage section 3 using welding rods that match carbon steel Q235 or low alloy high strength steel Q355. Ordinary weld 100 covers the extension line of the inner wall of unloading section 4.

[0081] S2. Weld the two ends of each internal stiffening rib steel 5 to the inner wall of the storage section 3 and the unloading section 4 respectively. Before welding, scrape off the stainless steel coating of the part to be welded in the unloading section 4.

[0082] Specifically, such as Figure 15 and Figure 16 As shown, the minimum net distance between the two ends of each internal stiffening rib steel 5 and the inner wall of the corresponding storage section 3 or the inner wall of the dropping section 4 is 10mm. The web plates of the internal stiffening rib steel 5 of each compartment plate 2 are connected to the inner wall of the storage section 3 or the inner wall of the dropping section 4 by a connecting angle steel 16 on each side. Ordinary welds 100 are formed by welding with welding rods that match carbon steel Q235 or low alloy high strength steel Q355. The connecting angle steel 16 is L100x12 and its length is 100mm less than the height of the internal stiffening rib steel 5. The ordinary weld 100 is a three-sided fillet weld and the weld leg size is the same as the thickness of the web plate of the internal stiffening rib steel 5.

[0083] Before welding the web of the internal stiffening rib steel 5 to the inner wall of the blanking section 4 via the connecting angle steel 16, the stainless steel coating on the inner wall of the blanking section 4 within the coverage area of ​​the connecting angle steel 16 is first peeled off or ground off to expose the base plate, and then the connecting angle steel 16 is welded to the base plate.

[0084] S3. Weld and fix one side of each plate 6, which is made of carbon steel or low alloy high strength steel, to the internal stiffening rib steel 5.

[0085] Specifically, such as Figure 17 and Figure 18 As shown, after covering the carbon steel or low-alloy high-strength steel side of each plate 6 onto both sides of the inner stiffening rib steel 5, the plate 6 on one side is first welded and fixed to the inner stiffening rib steel 5 as a whole. Taking the welding of the left plate 6 as an example, the left plate 6 is first welded and assembled as a whole in advance. After welding the left plate 6, the other plate 6 is cut into bevels according to the spacing of the inner stiffening rib steel 5. The bottom of the bevel is exposed with a stainless steel cladding. Each bevel joint is pressed against the center of the flange of each stiffening rib steel. The bevel gap is 5mm, the bottom thickness is 2mm, and the angle is 65°±5°. Then, using welding rods that match carbon steel Q235 or low-alloy high-strength steel Q355, the base plate of plate body 6 and the internal stiffening rib section steel 5 are welded to form a normal weld 100. Then, a transition weld 200 is welded using a transition welding rod that matches the stainless steel cladding. The top surface of the transition weld 200 is controlled to be 0.5mm to 1.5mm higher than the interface between the base plate and the cladding. Finally, a stainless steel weld 300 is welded using a stainless steel cladding welding rod.

[0086] S4. The inner wall of the storage section 3 is welded and fixed to one side of the inward stiffening rib steel 5 of the plate 6, and the stainless steel cladding on the other side of the inner wall of the storage section 3 is welded and fixed to the plate 6 by transition welding rod.

[0087] Specifically, such as Figure 19 As shown, bevels are first made at both ends of plate 6, with a 2mm gap between the bevel and the inner wall of storage section 3, a bevel thickness of 2mm, and an angle of 45°±5°. During welding, a common weld 100 is formed by welding the base plate of plate 6 and the inner wall of storage section 3 with a welding rod that matches carbon steel Q235 or low alloy high strength steel Q355. The top surface of the common weld 100 is controlled at a position 1.5mm to 2.5mm away from the interface. Then, a transition weld 200 is welded using a transition welding rod that matches the stainless steel cladding. The top surface of the transition weld 200 is flush with the outer surface of the stainless steel cladding.

[0088] S5. The inner wall of the blanking section 4 is welded to one side of the inward stiffening rib steel 5 of the plate 6 by a transition welding rod, and the inner wall of the blanking section 4 is welded to the stainless steel cladding on the other side of the plate 6.

[0089] Specifically, such as Figure 20As shown, in step S5, bevels are first made at both ends of the plate 6, with a gap of 2mm between the bevel and the inner wall of the storage section 3, and a bevel thickness of 10mm at the bottom. During welding, the inner side of the base plate of the plate 6 is not welded. First, a transition weld 200 is welded using a transition welding rod that matches the stainless steel cladding. The top surface of the transition weld 200 is controlled to be 0.5mm to 1.5mm higher than the interface. Finally, a stainless steel weld 300 is welded using a stainless steel cladding welding rod.

[0090] After the hopper body 1 and the compartment plate 2 are welded together, the top cover of the coal hopper is welded together to seal it. The top cover adopts existing technology, which will not be described in detail here.

[0091] When selecting welding electrodes that match carbon steel Q235 or low-alloy high-strength steel Q355, E4303 electrodes are generally suitable for Q235 steel; for Q355 steel, E5015 and E5016 electrodes are recommended. When Q235 and Q355 steels need to be welded together, E50 series electrodes can be considered. When selecting welding electrodes, the properties of the base material, welding conditions, and the quality requirements of the weld joint must be considered.

[0092] When selecting transition electrodes, for welding carbon steel Q235 or low-alloy high-strength steel Q355 to stainless steel cladding, 316L stainless steel electrodes, E7018 electrodes, nickel-based alloy electrodes, or dissimilar steel electrodes can be chosen. When selecting electrodes, the properties of the base material, welding conditions, and the quality requirements of the weld joint must be considered.

[0093] When selecting welding electrodes for stainless steel cladding, austenitic stainless steel electrodes such as A102 and A132 are typically chosen for austenitic stainless steel; martensitic stainless steel electrodes such as G202 and G207 can be selected for martensitic stainless steel, but preheating before welding and tempering after welding are necessary; and ferritic stainless steel electrodes such as G302 and G307 can be selected for ferritic stainless steel. The appropriate welding material should be chosen based on factors such as the composition of the base metal, welding conditions, and the operating environment.

[0094] In summary, the coal hopper and its welding method provided in this embodiment of the invention fix the inner wall of the storage section to both ends of each internal stiffening rib steel by welding, the inner wall of the storage section to the side of the plate facing the internal stiffening rib steel by welding, and the inner wall of the storage section to the stainless steel cladding of the plate by welding with transition welding rods.

[0095] The inner wall of the blanking section is covered with a stainless steel coating. The stainless steel coating on the inner wall of the blanking section near the front and rear ends of each internal stiffening rib is scraped off so that it can be welded and fixed to the ends of each internal stiffening rib.

[0096] The inner wall of the blanking section is welded to one side of the plate facing the inward stiffening ribs using transition welding rods, and the inner wall of the blanking section is welded and fixed to the stainless steel cladding on the other side of the plate.

[0097] This allows for direct welding of the same material parts of different components in the coal hopper. For welding between parts of different materials, methods such as scraping off the stainless steel coating or using transition welding rods are employed. This avoids the problem of electrochemical corrosion that easily occurs when directly welding different metal materials in traditional coal hoppers, leading to a decrease in the strength of the welded parts. This ensures the strength and durability of the welded joints, effectively extends the service life of the coal hopper, and significantly reduces the safety hazards caused by weld failure due to bimetallic corrosion.

[0098] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A coal hopper with compartments, comprising a hopper body (1) and a compartment plate (2), wherein the hopper body (1) comprises a storage section (3) and a discharge section (4) connected vertically, and the compartment plate (2) is vertically disposed within the hopper body (1) and extends from the storage section (3) to the bottom of the discharge section (4), characterized in that: The compartment plate (2) includes several vertically arranged internal stiffening ribs (5) and plates (6) welded to the left and right sides of the internal stiffening ribs (5). The webs of each internal stiffening rib (5) are placed horizontally. The material of each of the internal stiffening ribs (5) is carbon steel or low alloy high strength steel, and the material of the side of each of the plates (6) facing the internal stiffening ribs (5) is carbon steel or low alloy high strength steel, and the other side of each of the plates (6) is provided with a stainless steel cladding. The inner wall of the storage section (3) is welded and fixed to both ends of each of the internal stiffening ribs (5), the inner wall of the storage section (3) is welded to the side of the plate (6) facing the internal stiffening ribs (5), and the inner wall of the storage section (3) is welded and fixed to the stainless steel cladding of the plate (6) by a transition welding rod. The inner wall of the material dropping section (4) is provided with a stainless steel coating. The stainless steel coating on the inner wall of the material dropping section (4) close to the front and rear ends of each of the internal stiffening ribs (5) is scraped off so as to weld and fix it to the ends of each of the internal stiffening ribs (5). The inner wall of the blanking section (4) is welded to the side of the plate (6) facing the inner stiffening rib (5) by a transition welding rod, and the inner wall of the blanking section (4) is welded and fixed to the stainless steel cladding on the other side of the plate (6).

2. The coal hopper with compartments according to claim 1, characterized in that: The side wall of the material dropping section (4) is made of stainless steel composite plate; the plate body (6) is made of stainless steel composite plate; Each of the stainless steel composite plates is made by direct rolling of the base layer and the cladding layer. The base layer is made of carbon steel or low alloy high-strength steel, and the cladding layer is made of stainless steel.

3. A coal hopper with compartments according to claim 1 or 2, characterized in that: All internally stiffened ribs (5) are either I-beams or H-beams.

4. A coal hopper with compartments according to claim 1 or 2, characterized in that: The storage section (3) and the unloading section (4) are provided with stiffening plates (7) in a ring shape on the outer side of their sidewalls, corresponding to the relative positions of the internal stiffening ribs (5).

5. A coal hopper with compartments according to claim 1 or 2, characterized in that: The thickness of the lower sidewall of the storage section (3) is greater than the thickness of the upper sidewall of the storage section (3), so that the lower sidewall of the storage section (3) forms a thickened plate (8). The inner surface of the thickened plate (8) is flush with the inner surface of the upper cylinder wall. The material dropping section (4) is welded and fixed to the thickened plate (8).

6. The welding method for the sub-compartment coal hopper according to any one of claims 1-5, characterized in that: S1. Prefabricate the storage section (3) and the unloading section (4) of the silo body (1) respectively, and weld the top of the unloading section (4) to the storage section (3) for fixation; S2. Weld the two ends of each internal stiffening rib steel (5) to the inner wall of the storage section (3) and the blanking section (4) respectively. Before welding, scrape off the stainless steel coating of the blanking section (4) to be welded. S3. Weld and fix one side of the carbon steel or low alloy high strength steel of each plate (6) to the internal stiffening rib steel (5); S4. The inner wall of the storage section (3) is welded and fixed to the side of the plate (6) facing the inner stiffening rib (5), and the stainless steel cladding of the inner wall of the storage section (3) is welded and fixed to the other side of the plate (6) by a transition welding rod. S5. The inner wall of the blanking section (4) is welded to the side of the plate (6) facing the inner stiffening rib (5) by a transition welding rod, and the inner wall of the blanking section (4) is welded and fixed to the stainless steel cladding on the other side of the plate (6).

7. The welding method according to claim 6, characterized in that: In step S1, the storage section (3) and the unloading section (4) of the silo body (1) are prefabricated respectively, and the top of the unloading section (4) is welded and fixed to the storage section (3) specifically as follows: The stainless steel cladding of the inner wall of the blanking section (4) is welded with a transition welding rod, and a transition weld (200) is formed after welding. The inner wall of the blanking section (4) and the inner wall of the storage section (3) are welded with a welding rod that matches carbon steel or low alloy high strength steel to form a normal weld (100).

8. The welding method according to claim 6, characterized in that: In step S3, the carbon steel or low-alloy high-strength steel side of each plate (6) is welded and fixed to the internal stiffening rib steel (5) as follows: One side of each plate (6) is made of carbon steel or low alloy high strength steel and is respectively covered on both sides of the inner stiffening rib steel (5). Then, the plate (6) on one side of the stiffening rib steel is welded. Then, the other side plate (6) is cut into bevels according to the spacing of each inner stiffening rib steel (5). The bevels expose the stainless steel cladding. The inner wall of the blanking section (4) and the inner wall of the storage section (3) are welded with welding rods that match the carbon steel or low alloy high strength steel to form a normal weld (100). The transition weld (200) is welded with transition welding rods that match the stainless steel cladding. The stainless steel weld (300) is welded with stainless steel cladding welding rods.

9. The welding method according to claim 6, characterized in that: In step S4, the inner wall of the storage section (3) is welded and fixed to the side of the plate (6) facing the inner stiffening rib (5), and the stainless steel cladding on the other side of the inner wall of the storage section (3) is welded and fixed to the plate (6) using transition welding rods. Specifically: Ordinary welds (100) are welded using welding rods that match carbon steel or low alloy high strength steel, and transition welds (200) are welded using transition welding rods that match the stainless steel cladding. The top surface of the transition welds (200) is flush with the outer surface of the stainless steel cladding.

10. The welding method according to claim 6, characterized in that: In step S5, the inner wall of the blanking section (4) is welded to the side of the plate (6) facing the inner stiffening rib (5) using a transition welding rod, and the inner wall of the storage section (3) is welded and fixed to the stainless steel cladding on the other side of the plate (6) specifically as follows: Transition welds (200) are performed using transition electrodes that match the stainless steel cladding, and stainless steel welds (300) are performed using stainless steel cladding electrodes.

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