Manufacturing method of fan casing with copper layer protection ring

Abstract

The invention provides a method for manufacturing a fan casing with a copper layer protection ring, which comprises the following steps of: welding a steel base plate and a copper clad plate to form a copper-steel composite plate by adopting an explosive welding method, rolling the copper-steel composite plate to form a casing barrel by using a plate rolling machine, and assembling and welding a support flange and a rib plate to form an external frame; an anti-deformation tool is used for installing and welding a machine shell barrel and an outer frame, the machine shell barrel and the outer frame are sent into an annealing furnace to eliminate residual stress after being installed and welded, flame heating and a jack are adopted for conducting shape correction and roundness correction operation on the machine shell barrel, the inner wall of the machine shell barrel is machined, and it is ensured that the thickness of a copper layer is controlled within the design range. The shell finished product has the advantages of being good in anti-vibration performance and free of looseness, the shell finished product does not need to enter the fan shell to check a protection ring, maintenance items are reduced, meanwhile, the labor intensity of maintenance workers is greatly relieved, the safety and reliability coefficient of a fan is improved, the reliability of a ventilation system is guaranteed, and then safe production of a mine is guaranteed.

Description

Technical Field

[0001] This invention relates to blower manufacturing equipment, and more particularly to a method for manufacturing a blower housing with a copper-layer protective ring. Background Technology

[0002] Patent document CN115502598B discloses a casing processing method, which involves welding each component of the upper casing and each component of the lower casing of an ultra-large axial flow compressor. The upper casing is fully welded and the lower casing is partially welded according to the design sequence. An air inlet and an air outlet are welded at the air inlet and air outlet on the side wall of the lower casing, respectively, to complete the welding of the lower casing. Post-weld stress relief and stabilization treatments are performed in sequence. The upper and lower casings are tested by a water pressure test. If they pass the test, the upper and lower casings are connected to complete the processing of the ultra-large axial flow compressor casing.

[0003] However, the protective rings of mine ventilation fan casings have traditionally been fixed with rivets or countersunk copper bolts. Regardless of the fixing method, they are susceptible to vibration from the machine body, easily causing the protective rings to loosen. This results in a smaller gap between the blades and the protective ring, failing to meet design requirements and posing a risk of blade damage due to friction. Furthermore, during long-term operation, the fan casing and protective rings are easily corroded by vaporized water in the ventilation duct (which contains toxic and harmful substances such as sulfur dioxide and hydrogen sulfide). This corrosion further exacerbates the loosening of other rivets. Using rivets or bolts requires maintenance workers to frequently tap and check for looseness in the protective rings, replacing or supplementing fasteners as needed. This increases the maintenance workload and the labor intensity of the maintenance workers. The aforementioned casing processing methods cannot solve this problem; therefore, it is necessary to optimize them to overcome these shortcomings. Summary of the Invention

[0004] The purpose of this invention is to provide a method for manufacturing a fan housing with a copper-layer protective ring.

[0005] The technical solution adopted by this invention to solve its technical problem is as follows:

[0006] A method for manufacturing a fan housing with a copper protective ring includes the following steps:

[0007] S1, a copper-steel composite plate is formed by welding a steel substrate and a copper cladding plate together using an explosive welding method;

[0008] S2, using a plate rolling machine to roll copper-steel composite plates into machine housing cylinders;

[0009] S3, the supporting flange and stiffening plate are welded together to form an external frame. Anti-deformation tooling is used to weld the casing cylinder to the external frame. After the casing cylinder and the external frame are welded together, they are sent to the annealing furnace to eliminate residual stress.

[0010] S4, flame heating and jack are used to straighten and round the shell cylinder;

[0011] S5, the inner wall of the shell cylinder is machined to ensure that the thickness of the copper layer is controlled within the design range, and the shell finished product is formed.

[0012] Specifically, in step S1:

[0013] The low-carbon steel is selected to make the steel base plate, the thickness of which is 10-20 mm, and the surface is polished to remove the oxide layer and oil stains to ensure cleanliness, so that the roughness of the surface to be welded is 3.2-6.3 μm;

[0014] The copper alloy is selected to make the copper clad plate, the thickness of which is 2-5 mm, and the surface is polished to remove the oxide layer and oil stains to ensure cleanliness, so that the roughness of the surface to be welded is 3.2-6.3 μm;

[0015] The low-explosive velocity explosive is selected, the velocity of which is 2000-3000 m / s, and the energy generated by the explosive is used to push the copper clad plate to collide with the steel base plate at high speed, so that they are welded with each other, and the melting of the material caused by too high velocity is avoided.

[0016] In step S1:

[0017] Plastic or metal spacers are arranged between the steel base plate and the copper clad plate to maintain the initial distance between the steel base plate and the copper clad plate, and the height of the spacers is 5-15 mm.

[0018] In step S2:

[0019] It is confirmed that there is no oil stain, iron filings or scratch on the surface of the roller and the pressure roller of the plate rolling machine to avoid contaminating the copper-steel clad plate, and a center line is drawn on the copper-steel clad plate in the width direction of the copper-steel clad plate as a half division mark according to the design size of the shell cylinder.

[0020] The copper-steel clad plate is laid flat on the feeding table of the plate rolling machine to ensure that the half division line is aligned with the center line of the plate rolling machine, and the plate rolling machine is started to pre-bend one end of the copper-steel clad plate, and the curvature radius is slightly larger than the target cylinder radius to form a guide radius and reduce edge warping during rolling. The copper-steel clad plate is uniformly rolled at low speed to form a semicircular cylinder, and after the rolling is completed, the semicircular cylinder is unloaded from the plate rolling machine.

[0021] The semicircular cylinder rolled for the first time is reloaded to align the butt joint edge with the center line of the plate rolling machine, and the plate rolling machine is started to slowly roll the semicircular cylinder to make the butt joint edge closely fit to form a complete cylinder.

[0022] In step S3:

[0023] The shell cylinder and the external frame are hoisted into the annealing furnace as a whole to ensure that the distance between the workpiece and the furnace wall is ≥100 mm to avoid local overheating;

[0024] During the heating process, the temperature rising speed is less than or equal to 50 DEG C / h from room temperature to 300 DEG C stage, so as to prevent the copper layer and the steel layer from being peeled off due to the difference in thermal expansion coefficient, and the temperature rising speed is less than or equal to 30 DEG C / h from 300 DEG C to the target temperature, so as to ensure that the heat is uniformly penetrated into the workpiece;

[0025] During the cooling process, the cooling speed is less than or equal to 30 DEG C / h at the stage of 600 DEG C to 400 DEG C in the annealing furnace, and the cooling is performed outside the annealing furnace at the stage of 400 DEG C.

[0026] In step S4:

[0027] The current ovality of the machine shell cylinder is measured, the maximum, minimum diameter and deviation value are recorded, and the heating position is determined according to the ovality deviation direction;

[0028] The flame is moved from the edge of the heating area to the center, and the target temperature is uniformly heated, the hydraulic jack is placed at the corresponding position of the minimum diameter of the cylinder, the jack is slowly pumped, and after the target value is lifted, the pressure is kept for 10-15 minutes to make the material plastic deformation sufficient.

[0029] The method has the advantages that:

[0030] The method adopts explosion welding to connect the protective ring and the machine shell, and the composite plate is formed, compared with the fixed sink rivet or sink bolt, the explosion welding is reliable, has the advantages of good anti-vibration performance and non-looseness.

[0031] After the explosion welding seam is self-inspected and qualified, maintenance is not needed, the fan is ensured to be stably operated, compared with the rivet or bolt fixed protective ring, the fan shell does not need to be entered to inspect the protective ring, the maintenance project is reduced, and the labor intensity of the maintenance worker is also greatly reduced.

[0032] The explosion welding fixed protective ring is very reliable after various detection and inspection, is not affected by the vibration of the fan body, the safety and reliability coefficient of the fan is further improved, the reliability of the ventilation system is ensured, and the safety production of the mine is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is the structural schematic diagram of the fan with the copper layer protective ring machine shell provided by the application;

[0034] Figure 2 is the structural schematic diagram of the steel base plate and the copper clad plate. DETAILED DESCRIPTION

[0035] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments but not all of the present application. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0036] Embodiment 1

[0037] As shown in Figure 1 , Figure 2 , the manufacturing method of the fan shell with copper layer protection ring provided by the present application comprises the following steps:

[0038] S1, using the method of explosive welding to weld the steel base plate and the copper clad plate to form a copper-steel composite plate:

[0039] The low-carbon steel Q245R is selected to make the steel base plate, the thickness of which is 15 mm, and the surface is polished to remove the oxide layer and oil stains to ensure cleanliness, so that the roughness of the surface to be welded is 4.5 μm;

[0040] The copper alloy H62 is selected to make the copper clad plate, the thickness of which is 3 mm, and the surface is polished to remove the oxide layer and oil stains to ensure cleanliness, so that the roughness of the surface to be welded is 5.0 μm;

[0041] The low-explosive velocity explosive is selected, the velocity of which is 2500 m / s, and the energy generated by the explosive is used to push the copper clad plate to collide with the steel base plate at high speed, so that they are welded with each other, and the material is prevented from melting due to too high velocity.

[0042] At the same time, plastic or metal pads can be arranged between the steel base plate and the copper clad plate to maintain the initial distance between the steel base plate and the copper clad plate, the height of which is 12 mm.

[0043] S2, using a plate rolling machine to roll the copper-steel composite plate to form a shell cylinder:

[0044] Confirming that the surface of the rolling shaft and the compression roller of the plate rolling machine is free of oil stains, iron filings or scratches to avoid contaminating the copper-steel composite plate, and according to the design size of the shell cylinder, a center line is drawn in the width direction of the copper-steel composite plate as a half mark;

[0045] Lay the copper-steel composite plate on the feed table of the plate rolling machine, ensure that the half-line is aligned with the center line of the plate rolling machine, start the plate rolling machine, and pre-bend one end of the copper-steel composite plate with a curvature radius slightly larger than the target cylinder radius to form a guide arc and reduce edge warping during rolling. Roll the copper-steel composite plate at a constant speed under low-speed conditions to form a semicircular cylinder. After rolling is completed, unload the semicircular cylinder from the plate rolling machine.

[0046] Re-feed the first-rolled semicircular cylinder, align the butt joint edge with the center line of the plate rolling machine, start the plate rolling machine, and slowly roll the semicircular cylinder to make the butt joint edge tightly fit to form a complete cylinder.

[0047] S3, the support flange is assembled with the rib plate to form an external frame, the machine shell cylinder is assembled with the external frame using a deformation prevention tool, and after the machine shell cylinder and the external frame are assembled, they are sent into an annealing furnace to eliminate residual stress;

[0048] In this step, the machine shell cylinder and the external frame are hoisted into the annealing furnace as a whole to ensure a distance of 90mm between the workpiece and the furnace wall to avoid local overheating;

[0049] During heating, the temperature rises at a speed of 40℃ / h from room temperature to 300℃ to prevent the copper layer and the steel layer from peeling due to the difference in thermal expansion coefficient, and the temperature rises at a speed of 25℃ / h from 300℃ to the target temperature to ensure uniform heat penetration into the workpiece;

[0050] During cooling, the temperature is cooled at a speed of 25℃ / h from 600℃ to 400℃ in the annealing furnace, and the temperature is cooled outside the annealing furnace at 400℃.

[0051] S4, flame heating and jack are used to straighten and round the machine shell cylinder:

[0052] Measure the current ovality of the machine shell cylinder, record the maximum, minimum diameter and deviation value, and determine the heating position according to the ovality deviation direction;

[0053] Move the flame from the edge of the heating area to the center and heat uniformly to the target temperature. Place a hydraulic jack at the corresponding position of the minimum diameter of the cylinder, slowly pump the jack, and keep the pressure for 12 minutes after lifting to the target value to make the material plastic deformation sufficient.

[0054] S5, machine the inner wall of the machine shell cylinder to ensure that the copper layer thickness is controlled within the design range to form a machine shell finished product.

[0055] Example 2:

[0056] Low carbon steel Q245R is selected to make the steel base plate, the thickness is 20mm, and the surface is polished to remove the oxide layer and oil stains, ensuring cleanliness, so that the roughness of the surface to be welded is 6.3μm; Copper alloy H62 is selected to make the copper clad plate, the thickness is 5mm, and the surface is polished to remove the oxide layer and oil stains, ensuring cleanliness, so that the roughness of the surface to be welded is 6.3μm; Low explosive is selected, the detonation velocity is 3000m / s, the energy generated by the explosive is used to push the copper clad plate to collide with the steel base plate at high speed, so that they are welded together, and the high explosive velocity is avoided to cause the material to melt. Plastic or metal pads are arranged between the steel base plate and the copper clad plate to maintain the initial distance between the steel base plate and the copper clad plate, and the height is 15mm.

[0057] Confirm that the surface of the roll shaft and the compression roller of the plate rolling machine is free of oil stains, iron filings or scratches to avoid contaminating the copper-steel composite plate. According to the design size of the shell cylinder, a center line is drawn in the width direction of the copper-steel composite plate as a half-splitting mark. The copper-steel composite plate is laid flat on the plate rolling machine feed table, ensuring that the half-splitting line is aligned with the center line of the plate rolling machine. The plate rolling machine is started, and one end of the copper-steel composite plate is pre-bent with a curvature radius slightly larger than the target cylinder radius to form a guide radius, reducing edge warping during rolling. The copper-steel composite plate is uniformly rolled at low speed to form a semicircular cylinder. After rolling is completed, the semicircular cylinder is removed from the plate rolling machine. The semicircular cylinder rolled the first time is reloaded with the butt joint edge aligned with the center line of the plate rolling machine. The plate rolling machine is started, and the semicircular cylinder is slowly rolled to make the butt joint edge closely fit to form a complete cylinder.

[0058] The support flange and the rib plate are assembled to form an external frame. The shell cylinder and the external frame are assembled using a deformation prevention tool. After the shell cylinder and the external frame are assembled, they are sent to an annealing furnace to eliminate residual stress. The shell cylinder and the external frame are lifted as a whole into the annealing furnace, ensuring a distance of 80mm between the workpiece and the furnace wall to avoid local overheating. During the heating process, the temperature is raised at a speed of 40℃ / h from room temperature to 300℃ to prevent the copper layer and the steel layer from peeling due to the difference in thermal expansion coefficient. The temperature is raised at a speed of 25℃ / h from 300℃ to the target temperature to ensure that the heat penetrates uniformly into the workpiece. During the cooling process, the temperature is cooled at a speed of 20℃ / h from 600℃ to 400℃ in the annealing furnace, and the temperature is cooled outside the annealing furnace at 400℃.

[0059] The current ovality of the shell cylinder is measured, and the maximum, minimum diameters and deviation values are recorded. The heating position is determined according to the ovality deviation direction. The flame is moved from the edge to the center of the heating area, and the target temperature is uniformly heated. A hydraulic jack is placed at the corresponding position of the minimum diameter of the cylinder, and the jack is slowly pumped to the target value. The pressure is maintained for 15 minutes to allow the material to plastically deform fully. Finally, the inner wall of the shell cylinder is machined to ensure that the thickness of the copper layer is controlled within the design range, and the shell finished product is formed.

[0060] Example 3:

[0061] Low carbon steel Q245R is selected to make steel base plate, the thickness is 10mm, and the surface is polished to remove the oxide layer and oil stains, ensuring cleanliness, so that the roughness of the surface to be welded is 3.2μm; Copper alloy H62 is selected to make copper clad plate, the thickness is 2mm, and the surface is polished to remove the oxide layer and oil stains, ensuring cleanliness, so that the roughness of the surface to be welded is 3.2μm; Low explosive is selected, the detonation velocity is 2000m / s, the energy generated by the explosive is used to push the copper clad plate to collide with the steel base plate at high speed, so that they are welded together, and the high explosive velocity is avoided to cause the material to melt. Plastic or metal pads are arranged between the steel base plate and the copper clad plate to maintain the initial distance between the steel base plate and the copper clad plate, and the height is 5mm.

[0062] It is confirmed that there is no oil stain, iron filings or scratch on the surface of the roll shaft and the compression roller of the plate rolling machine to avoid contaminating the copper-steel composite plate. According to the design size of the shell cylinder, a center line is drawn in the width direction of the copper-steel composite plate as a half division mark. The copper-steel composite plate is laid flat on the feeding table of the plate rolling machine, and it is ensured that the half division line is aligned with the center line of the plate rolling machine. The plate rolling machine is started, and one end of the copper-steel composite plate is pre-bent. The curvature radius is slightly larger than the target cylinder radius to form a guide radius, which reduces the edge warping during rolling. The copper-steel composite plate is uniformly rolled at low speed to form a semicircular cylinder. After the rolling is completed, the semicircular cylinder is unloaded from the plate rolling machine. The semicircular cylinder rolled in the first time is reloaded so that the butt joint edge is aligned with the center line of the plate rolling machine. The plate rolling machine is started, and the semicircular cylinder is slowly rolled so that the butt joint edge is tightly fitted to form a complete cylinder.

[0063] The support flange and the rib plate are assembled to form an external frame. The shell cylinder and the external frame are assembled using a deformation prevention tool. After the shell cylinder and the external frame are assembled, they are sent into an annealing furnace to eliminate residual stress. The shell cylinder and the external frame are hoisted into the annealing furnace as a whole to ensure that the distance between the workpiece and the furnace wall is 100mm to avoid local overheating. During the heating process, the temperature rises at a speed of 50℃ / h from room temperature to 300℃ to prevent the copper layer and the steel layer from being separated due to the difference in thermal expansion coefficient. The temperature rises at a speed of 30℃ / h from 300℃ to the target temperature to ensure that the heat is uniformly penetrated into the workpiece. During the cooling process, the temperature is cooled at a speed of 30℃ / h from 600℃ to 400℃ in the annealing furnace, and the temperature is cooled outside the annealing furnace at 400℃.

[0064] The current ovality of the shell cylinder is measured, and the maximum, minimum diameter and deviation value are recorded. The heating position is determined according to the ovality deviation direction. The flame is moved from the edge to the center of the heating area, and the target temperature is uniformly heated. A hydraulic jack is placed at the corresponding position of the minimum diameter of the cylinder. The jack is slowly pumped and lifted to the target value, and the pressure is maintained for 10 minutes to make the material plastic deformation sufficient. Finally, the inner wall of the shell cylinder is machined to ensure that the thickness of the copper layer is controlled within the designed range to form a shell finished product.

[0065] In the description of the application, it should be noted that when the terms indicating the orientation or positional relationship of "up", "down", "inner", "outer", "left", "right" and the like appear, it should be understood as based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly placed when the product of the application is used, or the orientation or positional relationship commonly understood by those skilled in the art, and is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application. In addition, when the terms "first", "second" and the like appear, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance. In the description of the application, it should also be noted that unless otherwise specifically specified and limited, the terms "mounting", "setting", "connecting" and the like should be understood in a broad sense, for example, "connecting" can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or can be electrically connected; can be directly connected, or indirectly connected through an intermediate medium; can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

Claims

1. A method for manufacturing a fan housing with a copper-layer protective ring, characterized in that, Includes the following steps: S1, a copper-steel composite plate is formed by welding a steel substrate and a copper cladding plate together using explosive welding. S2, using a plate rolling machine to roll copper-steel composite plates into machine housing cylinders; S3, the supporting flange and stiffening plate are welded together to form an external frame. Anti-deformation tooling is used to weld the casing cylinder to the external frame. After the casing cylinder and the external frame are welded together, they are sent to the annealing furnace to eliminate residual stress. S4 uses flame heating and jacks to straighten and round the casing cylinder; S5, the inner wall of the casing is machined to ensure that the copper layer thickness is controlled within the design range, forming the finished casing.

2. The manufacturing method of a fan housing with a copper protective ring according to claim 1, characterized in that, In step S1: The steel substrate is made of low carbon steel with a thickness of 10-20mm. The surface is polished to remove the oxide layer and oil stains to ensure cleanliness, so that the roughness of the surface to be welded is 3.2-6.3μm. Copper alloy is selected to make copper cladding plates with a thickness of 2-5mm. The surface is polished to remove oxide layer and oil stains to ensure cleanliness, so that the roughness of the surface to be welded is 3.2-6.3μm. Low-velocity explosives with a detonation velocity of 2000-3000 m / s are selected. The energy generated by the explosives is used to propel the copper cladding plate to collide with the steel substrate at high speed, so that they are welded together, while avoiding the melting of materials due to excessively high detonation velocities.

3. The method for manufacturing a fan housing with a copper protective ring according to claim 2, characterized in that, In step S1: A plastic or metal spacer is placed between the steel substrate and the copper clad plate to maintain the initial gap between them, with a height of 5 to 15 mm.

4. The method for manufacturing a fan housing with a copper protective ring according to claim 1, characterized in that, In step S2: Confirm that the rollers and pressure rollers of the plate rolling machine are free of oil, iron filings or scratches to avoid contaminating the copper-steel composite plate. According to the design dimensions of the machine casing, draw the center line in the width direction of the copper-steel composite plate as a half mark. Lay the copper-steel composite plate flat on the feed table of the plate rolling machine, ensuring that the split line is aligned with the center line of the plate rolling machine. Start the plate rolling machine and pre-bend one end of the copper-steel composite plate with a curvature radius slightly larger than the target cylinder radius to form a guiding arc and reduce edge warping during rolling. Roll the copper-steel composite plate at a low speed to form a semi-cylinder. After rolling, remove the semi-cylinder from the plate rolling machine. Reload the semi-cylindrical body that was rolled the first time, align the mating edge with the center line of the plate rolling machine, start the plate rolling machine, and slowly roll the semi-cylindrical body to make the mating edge fit tightly together and form a complete cylinder.

5. The method for manufacturing a fan housing with a copper protective ring according to claim 1, characterized in that, In step S3: The casing and external frame are hoisted into the annealing furnace as a whole, ensuring that the distance between the workpiece and the furnace wall is ≥100mm to avoid local overheating. During the heating process, from room temperature to 300℃, the heating rate is ≤50℃ / h to prevent the copper layer and steel layer from peeling due to the difference in thermal expansion coefficients. From 300℃ to the target temperature, the heating rate is ≤30℃ / h to ensure that the heat penetrates evenly into the workpiece. During the cooling process, in the 600-400℃ stage, cooling is carried out inside the annealing furnace at a cooling rate of ≤30℃ / h, and in the 400℃ stage, cooling is carried out outside the annealing furnace.

6. The method for manufacturing a fan housing with a copper protective ring according to claim 1, characterized in that, In step S4: Measure the current ellipticity of the casing, record the maximum and minimum diameters and deviation values, and determine the heating position based on the direction of the ellipticity deviation. Move the flame from the edge of the heating area toward the center to heat it evenly to the target temperature. Place a hydraulic jack at the corresponding position of the smallest diameter of the cylinder and slowly pump the jack to lift it to the target value. Maintain the pressure for 10 to 15 minutes to allow the material to undergo sufficient plastic deformation.

Images