A hot-dip galvanizing apparatus and a hot-dip galvanizing process

Abstract

The application relates to a hot-dip galvanizing device, which comprises an immersion tank, feeding conveying belts and discharging conveying belts arranged at the two ends of the immersion tank respectively, the feeding conveying belts are arranged in the immersion tank at one end and outside the immersion tank at the other end, the discharging conveying belts are arranged in the immersion tank at one end and outside the immersion tank at the other end, and the feeding conveying belts are arranged above the discharging conveying belts at the gap between the two ends of the feeding conveying belts. The application has the effect of improving the galvanizing quality of workpieces.

Description

Technical Field

[0001] This application relates to the field of zinc plating of workpieces, and in particular to a hot-dip galvanizing equipment and a hot-dip galvanizing process. Background Technology

[0002] Hot-dip galvanizing, also known as hot-dip zinc plating, involves reacting molten metal with an iron substrate to create an alloy layer, thus bonding the substrate and the coating. The process begins with pickling the steel parts to remove iron oxide from their surface. After pickling, the parts are cleaned in an aqueous solution of ammonium chloride or zinc chloride, or a mixture of both, before being immersed in the hot-dip galvanizing bath. Hot-dip galvanizing offers advantages such as uniform coating, strong adhesion, and long service life.

[0003] A Chinese invention patent with publication number CN115044849A discloses an apparatus for continuous hot-dip galvanizing of steel strip, comprising a solvent tank and a hot-dip galvanizing tank. A first support plate is fixedly connected between the solvent tank and the hot-dip galvanizing tank. A second support plate is fixedly connected to the side of the solvent tank away from the first support plate. A third support plate is fixedly connected to the side of the hot-dip galvanizing tank away from the first support plate. A transmission mechanism is provided between the second support plate and the third support plate for conveying the steel strip to be galvanized. Two inclined first boxes are arranged above the first support plate. A connecting block is fixedly connected to the sides of both first boxes. The bottom of the lower first box is connected by a first mounting plate. The first housing is fixedly connected to the top of the first support plate. A first plane and a second plane are provided on the first and second planes, respectively, with a plurality of air outlets equidistantly spaced on each plane. An internal shielding mechanism is provided inside the first housing to shield the air outlets. A blower mechanism is provided on the side of the first housing to activate the shielding mechanism, removing the shielding from the air outlets and blowing hot air through them onto the surface of the strip. A wiping mechanism is provided between the two first housings to wipe away excess solution from both sides of the strip. A preheating mechanism is provided at the top of the first support plate to heat the dried strip.

[0004] Existing hot-dip galvanizing equipment uses a conveyor belt to feed workpieces into the hot-dip galvanizing bath for hot-dip galvanizing, and then sends the workpieces out of the hot-dip galvanizing bath via the same conveyor belt. Throughout the process, the area where the conveyor belt contacts the workpiece is always in contact with the conveyor belt, which can easily lead to the inability to galvanize properly in the contact area, thus affecting the galvanizing quality of the workpiece. Summary of the Invention

[0005] To improve the galvanizing quality of workpieces, this application provides a hot-dip galvanizing apparatus.

[0006] The hot-dip galvanizing equipment provided in this application adopts the following technical solution:

[0007] A hot-dip galvanizing apparatus includes a plating tank. At both ends of the plating tank along its length are respectively a feed conveyor belt for conveying material into the plating tank and a discharge conveyor belt for conveying material out of the plating tank. One end of the feed conveyor belt extends into the plating tank, and the other end is positioned outside the plating tank. One end of the discharge conveyor belt is installed inside the plating tank, and the other end extends out of the plating tank. The end of the feed conveyor belt extending into the plating tank is positioned slightly above the discharge conveyor belt.

[0008] By adopting the above technical solution, the workpiece is transported to the immersion plating tank by the feeding conveyor belt and then falls onto the discharge conveyor belt. The discharge conveyor belt sends the workpiece out of the immersion plating tank after immersion plating. During the immersion plating process, the workpiece changes conveyor belts, and all surfaces of the workpiece are in contact with the zinc liquid in the immersion plating tank. This reduces the probability of poor immersion plating effect in some areas due to the workpiece sticking to the conveyor belt, and improves the zinc plating quality of the workpiece.

[0009] Optionally, a guide plate is provided in the immersion plating tank. The guide plate is located between the feed conveyor belt and the discharge conveyor belt. There are two guide plates, which are respectively located in the wide direction of the immersion plating tank and are inclined towards the center of the immersion plating tank.

[0010] By adopting the above technical solution, the guide plate can guide the workpiece, causing it to fall to the middle of the discharge conveyor belt, thus reducing the probability of the workpiece falling randomly and hitting the side wall of the immersion tank and causing damage.

[0011] Optionally, a receiving tank is provided below the end of the discharge conveyor belt that extends out of the immersion tank.

[0012] By adopting the above technical solution, the collection tank can receive zinc liquid that adheres to the workpiece but is not plated on it, reducing the probability of zinc liquid dripping everywhere and affecting the working environment.

[0013] Optionally, a rinsing mechanism is provided on the side of the discharge conveyor belt away from the collection tank. The rinsing mechanism includes a rinsing pipe and spray heads. The rinsing pipe is installed on the discharge conveyor belt along the width direction of the collection tank. The spray heads are connected to and communicate with the rinsing pipe. Several spray heads are evenly arranged above the discharge conveyor belt along the length direction of the rinsing pipe.

[0014] By adopting the above technical solution, the rinsing mechanism can rinse the galvanized workpiece, washing off the zinc liquid adhering to the workpiece surface. At the same time, the rinsing mechanism can also quickly cool the workpiece, facilitating subsequent processing.

[0015] Optionally, a filter screen is provided inside the storage pool, and the filter screen divides the storage pool.

[0016] By adopting the above technical solution, after the zinc liquid is flushed into the collection tank by water, it will cool and solidify upon contact with the water in the collection tank. The filter screen can filter out the cooled and solidified zinc, which facilitates subsequent processing.

[0017] Optionally, a return pipe is installed on the storage tank, with its two ends connected to the storage tank and the rinsing pipe, respectively, and the return pipe connecting the storage tank and the rinsing pipe.

[0018] By adopting the above technical solution, the reflux pipe can send the filtered water back into the flushing pipe, thereby realizing water recycling and saving water resources.

[0019] Optionally, a tapping mechanism is provided above the receiving pool. The tapping mechanism is located on the side of the rinsing mechanism away from the immersion pool. The tapping mechanism includes a rotating disk and tapping rollers. The rotating disk is rotatably located above the receiving pool, and the tapping rollers are eccentrically located on the rotating disk. The rotation of the rotating disk drives the tapping rollers to tap the discharge conveyor belt between gaps.

[0020] By adopting the above technical solution, the slapping mechanism can accelerate the removal of water from the workpiece by slapping and vibrating it.

[0021] Optionally, a brush roller is rotatably mounted on the receiving pool, positioned above the discharge conveyor belt, with bristles evenly distributed on the brush roller, the bristles abutting against the workpiece placed on the discharge conveyor belt.

[0022] By adopting the above technical solution, the rotation of the brush roller causes the bristles to remove water and debris adhering to the workpiece.

[0023] Optionally, a linkage mechanism is provided between the brush roller and the rotating disk, and the brush roller drives the rotating disk to rotate through the linkage mechanism.

[0024] By adopting the above technical solution, the linkage mechanism can realize the linkage between the brush roller and the rotating disk, reduce the need for a power mechanism, and save costs and energy.

[0025] A hot-dip galvanizing process using hot-dip galvanizing equipment includes the following steps:

[0026] S1: Degreasing, degreasing the workpiece and cleaning the grease from the surface of the workpiece;

[0027] S2: Pickling, the degreased workpiece is placed in the pickling tank for pickling to remove the oxide layer and rust spots on the surface of the workpiece;

[0028] S3: Immersion washing, the pickled workpiece is placed in an immersion bath with a plating flux solution for immersion washing;

[0029] S4: Hot-dip galvanizing, which involves placing the workpiece in a galvanizing bath to form a zinc coating on the surface of the workpiece.

[0030] S5: Cooling, rinsing the workpiece after galvanizing to cool it down;

[0031] S6: Passivation. The galvanized workpiece is placed in a passivation bath for passivation treatment, so that the surface of the workpiece is covered with a passivation film.

[0032] By adopting the above technical solution, the workpiece is pretreated by degreasing, pickling and immersion, which reduces the impact of grease and rust spots on the workpiece on the galvanizing process.

[0033] In summary, this application includes at least one of the following beneficial technical effects:

[0034] 1. After the workpiece is conveyed into the immersion plating tank by the feeding conveyor belt, it leaves the feeding conveyor belt and falls onto the discharge conveyor belt. The discharge conveyor belt sends the workpiece out of the immersion plating tank after immersion plating. During the immersion plating process, the workpiece changes conveyor belts, and all surfaces of the workpiece are in contact with the zinc liquid in the immersion plating tank. This reduces the probability of poor immersion plating effect in some areas due to the workpiece sticking to the conveyor belt, and improves the zinc plating quality of the workpiece.

[0035] 2. The guide plate can guide the workpiece, so that the workpiece falls to the middle of the discharge conveyor belt, reducing the probability of the workpiece falling randomly and hitting the side wall of the immersion tank and causing damage.

[0036] 3. The collection tank can receive zinc liquid that is not plated on the workpiece, reducing the probability of zinc liquid dripping everywhere and affecting the working environment;

[0037] 4. The rinsing mechanism can rinse the galvanized workpiece, washing off the zinc liquid adhering to the workpiece surface. At the same time, the rinsing mechanism can also quickly cool the workpiece, facilitating subsequent processing.

[0038] 5. The reflux pipe allows filtered water to be returned to the flushing pipe, thus achieving water recycling and saving water resources;

[0039] 6. The tapping mechanism can accelerate the removal of water from the workpiece by tapping and vibrating it;

[0040] 7. The rotating brush roller causes the bristles to remove water and debris adhering to the workpiece. Attached Figure Description

[0041] Figure 1 This is a cross-sectional structural diagram of this embodiment.

[0042] Figure 2 This is a schematic diagram of the overall structure of this embodiment.

[0043] Figure 3 yes Figure 2 A magnified view of section A in the middle.

[0044] Figure 4 yes Figure 2 A magnified view of section B in the middle.

[0045] Explanation of reference numerals in the attached drawings: 0. Mounting frame; 1. Immersion tank; 2. Feeding conveyor belt; 3. Discharge conveyor belt; 4. Guide plate; 5. Collection tank; 6. Washing mechanism; 61. Washing pipe; 62. Spray head; 7. Filter screen; 8. Return pipe; 9. Beating mechanism; 91. Rotating disc; 92. Beating roller; 10. Brush roller; 11. Brush bristles; 12. Adjusting component; 121. Adjusting platform; 122. Adjusting slider; 123. Adjusting bolt; 13. Linkage mechanism; 131. Synchronous pulley; 132. Synchronous belt. Detailed Implementation

[0046] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0047] This application discloses a hot-dip galvanizing apparatus, including a rectangular immersion bath 1, as shown in the following embodiments. Figure 1 and Figure 2 The immersion plating tank 1 has mounting frames 0 at both ends along its length. Each mounting frame 0 is equipped with a conveyor belt, which is a mesh conveyor belt. The end of the conveyor belt away from the mounting frame 0 extends into the immersion plating tank 1. The conveyor belt at one end of the immersion plating tank 1 is the feeding conveyor belt 2, which conveys the workpiece towards the immersion plating tank 1. The conveyor belt at the other end of the immersion plating tank 1 is the discharging conveyor belt 3, which conveys the workpiece away from the immersion plating tank 1. The gap between the end of the feeding conveyor belt 2 extending into the immersion plating tank 1 and the discharging conveyor belt 3 is set above the discharging conveyor belt 3. The workpiece is fed into the immersion plating tank 1 from the feeding conveyor belt 2, leaves the feeding conveyor belt 2 when it falls into the immersion plating tank 1, and then falls onto the discharging conveyor belt 3. The discharging conveyor belt 3 then sends the workpiece out of the immersion plating tank 1. During the transfer from the feeding conveyor belt 2 to the discharging conveyor belt 3, the workpiece detaches from the conveyor belt. Therefore, there is no situation where the workpiece is partially blocked due to the conveyor belt, preventing normal immersion plating and improving the zinc plating quality of the workpiece.

[0048] Reference Figure 1 and Figure 2 The immersion plating tank 1 is equipped with a guide plate 4, which is located between the feed conveyor belt 2 and the discharge conveyor belt 3. There are two guide plates 4, which are respectively located in the wide direction of the immersion plating tank 1. The two guide plates 4 are inclined towards the center of the immersion plating tank 1. The guide plates 4 can guide the workpiece so that it falls to the middle of the discharge conveyor belt 3, reducing the probability of the workpiece falling randomly and hitting the side wall of the immersion plating tank 1 and causing damage.

[0049] Reference Figure 2 and Figure 3A receiving tank 5 is provided below one end of the discharge conveyor belt 3 extending from the immersion tank 1. The receiving tank 5 can receive zinc liquid that adheres to the workpiece but is not plated on it, reducing the probability of zinc liquid dripping everywhere and affecting the working environment. A rinsing mechanism 6 is provided on the side of the discharge conveyor belt 3 away from the receiving tank 5. The rinsing mechanism 6 includes a rinsing pipe 61 mounted on the mounting frame 0 along the wide direction of the discharge conveyor belt 3 and several spray heads 62 mounted on the rinsing pipe. The spray heads 62 are connected to and communicate with the rinsing pipe 61. The spray heads 62 are evenly arranged along the length of the rinsing pipe 61 along the discharge conveyor belt 3. Above belt 3, rinsing pipe 61 is connected to a water source to supply water to spray head 62. Spray head 62 sprays water towards discharge conveyor belt 3. The rinsing mechanism 6 can rinse the galvanized workpiece, washing off the zinc liquid adhering to the workpiece surface. At the same time, the rinsing mechanism 6 can also quickly cool the workpiece, facilitating subsequent processing. A filter screen 7 is installed in the collection tank 5. The filter screen 7 divides the collection tank 5. After the zinc liquid is flushed into the collection tank 5 by water, it will cool and solidify after contact with the water in the collection tank 5. The filter screen 7 can filter out the cooled and solidified zinc, facilitating subsequent processing.

[0050] Reference Figure 2 and Figure 3 A return pipe 8 is installed on the collection tank 5. The two ends of the return pipe 8 are connected to the collection tank 5 and the rinsing pipe 61 respectively. The return pipe 8 connects the collection tank 5 and the rinsing pipe 61. The setting of the return pipe 8 can send the filtered water back into the rinsing pipe 61, thereby realizing the recycling of water and saving water resources.

[0051] Reference Figure 2 and Figure 4A beating mechanism 9 is installed above the receiving tank 5. The beating mechanism 9 is located on the side of the rinsing mechanism 6 away from the immersion tank 1. The beating mechanism 9 includes a rotating disk 91 rotatably mounted on the mounting bracket 0 above the receiving tank 5 and a beating roller 92 eccentrically mounted on the rotating disk 91. The rotating disk 91 drives the beating roller 92 to intermittently beat the discharge conveyor belt 3. The beating mechanism 9 can accelerate the dripping of water from the workpiece by beating and vibrating it. A brush roller 10 is rotatably mounted on the receiving tank 5. On the mounting frame 0, a brush roller 10 is positioned above the discharge conveyor belt 3. Brush bristles 11 are evenly distributed on the brush roller 10, and these bristles 11 abut against the workpiece placed on the discharge conveyor belt 3. The rotation of the brush roller 10 causes the bristles 11 to remove water and debris adhering to the workpiece. An adjustment assembly 12 is provided between the mounting frame 0 and the brush roller 10. The adjustment assembly 12 includes an adjustment platform 121 fixed to the mounting frame 0, an adjustment slider 122 slidably disposed on the adjustment platform 121 in a vertical direction, and a component threadedly connected to the adjustment platform 121. An adjusting bolt 123 is rotatably connected to the adjusting slider 122. The brush roller 10 is rotatably mounted on the adjusting slider 122. Driving the adjusting bolt 123 to rotate clockwise raises the adjusting slider 122 on the adjusting platform 121, and driving the adjusting bolt 123 to rotate counterclockwise lowers the adjusting slider 122 on the adjusting platform 121. The height of the roller is adjusted by the adjusting assembly 12, allowing the roller to be adjusted according to the height of the workpiece to improve the cleaning effect. A linkage mechanism 13 is provided between the brush roller 10 and the rotating disk 91. The linkage mechanism 13 includes two synchronous pulleys 131 and a synchronous belt 132 sleeved on the two synchronous pulleys 131. The two synchronous pulleys 131 are coaxially fixed to the brush roller 10 and the rotating disk 91, respectively. The rotation of the brush roller 10 drives the rotating disk 91 to rotate through the synchronous belt 132 and the synchronous pulleys 131. The brush roller 10 can be driven by a motor or driven by the workpiece. The linkage mechanism 13 enables the linkage between the brush roller 10 and the rotating disk 91, reducing the need for a power mechanism and saving costs and energy.

[0052] A hot-dip galvanizing process using hot-dip galvanizing equipment includes the following steps: S1: Degreasing, the workpiece is degreased by immersion in a chemical medium to remove grease from the surface. After degreasing, the workpiece is rinsed in water to reduce the impact of the chemical medium on subsequent processing; S2: Pickling, the degreased and rinsed workpiece is placed in a pickling tank to remove the oxide layer and rust from the surface, reducing their impact on subsequent plating. After pickling, the workpiece is also rinsed in water to reduce the impact of the acid solution on subsequent plating; S3: Immersion rinsing, the pickled and rinsed workpiece is immersed in an immersion tank 1 containing a plating flux solution. Because the surface of the workpiece is relatively clean and highly reactive after pickling, it is easily oxidized when exposed to air. Immersion rinsing can prolong the time before rust reappears, reducing the probability of the workpiece re-oxidizing and rusting before galvanizing. Plating flux is supplemented with plaster powder, hydroxypropyl methylcellulose, and allyl alcohol polyoxypropylene ether. This reduces the surface tension of the zinc bath, removes iron salts and other impurities from the workpiece surface, and makes it easier for the zinc bath to adhere to the workpiece surface, enhancing the wear resistance of the zinc plating layer. After immersion, the workpiece needs to be dried to reduce the impact of liquid residue on subsequent plating. S4: Zinc immersion – The workpiece is placed in immersion bath 1 containing zinc solution for hot-dip galvanizing, forming a zinc plating layer on the workpiece surface. S5: Cooling – The galvanized workpiece is rinsed to cool it, facilitating subsequent processing. Rinsing also removes any adhering zinc solution, reducing the impact of unplated zinc solution on subsequent processing. S6: Passivation – The galvanized workpiece is placed in a passivation bath for passivation treatment, covering the workpiece surface with a passivation film. This passivation film reduces the probability of oxidation and white rust formation on the workpiece.

[0053] The implementation principle of this application embodiment is as follows: the workpiece after immersion and drying is placed on the feeding conveyor belt 2, and the workpiece is transported to the immersion plating tank 1 by the feeding conveyor belt 2, so that the workpiece is separated from the feeding conveyor belt 2 and falls in the zinc liquid. The workpiece is guided to the discharge conveyor belt 3 by the guide plate 4, and then the workpiece is transported out of the immersion plating tank 1 by the discharge conveyor belt 3. After the workpiece leaves the immersion plating tank 1, it is cooled and rinsed by the rinsing mechanism 6, so that the workpiece is cooled and the zinc liquid adhering to the surface is washed away. Then, the surface is brushed by the brush roller 10 and the workpiece is vibrated by the tapping mechanism 9, so that the water and debris adhering to the workpiece fall off, and the immersion plating of the workpiece is completed.

[0054] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A hot-dip galvanizing apparatus, comprising an immersion plating bath (1), characterized in that: The immersion plating tank (1) is provided with a feeding conveyor belt (2) that conveys material into the immersion plating tank (1) and a discharging conveyor belt (3) that conveys material out of the immersion plating tank (1) at both ends along its length. One end of the feeding conveyor belt (2) extends into the immersion plating tank (1) and the other end is erected outside the immersion plating tank (1). One end of the discharging conveyor belt (3) is installed inside the immersion plating tank (1) and the other end extends out of the immersion plating tank (1). The end of the feeding conveyor belt (2) that extends into the immersion plating tank (1) is spaced above the discharging conveyor belt (3). The immersion plating tank (1) is provided with a guide plate (4), which is located between the feed conveyor belt (2) and the discharge conveyor belt (3). There are two guide plates (4), which are respectively located in the wide direction of the immersion plating tank (1) and are inclined towards the center of the immersion plating tank (1). The discharge conveyor belt (3) extends out of the immersion tank (1) and a receiving tank (5) is provided below one end. A rinsing mechanism (6) is provided on the side of the discharge conveyor belt (3) away from the collection tank (5). The rinsing mechanism (6) includes a rinsing pipe (61) and a spray head (62). The rinsing pipe (61) is installed on the discharge conveyor belt (3) along the wide width direction of the collection tank (5). The spray head (62) is connected to and communicates with the rinsing pipe (61). Several spray heads (62) are evenly arranged above the discharge conveyor belt (3) along the length direction of the rinsing pipe (61). The storage pool (5) is equipped with a filter screen (7), which separates the storage pool (5). A beating mechanism (9) is provided above the collection pool (5). The beating mechanism (9) is located on the side of the rinsing mechanism (6) away from the immersion pool (1). The beating mechanism (9) includes a rotating disk (91) and a beating roller (92). The rotating disk (91) is rotatably located above the collection pool (5). The beating roller (92) is eccentrically located on the rotating disk (91). The rotating disk (91) drives the beating roller (92) to beat the discharge conveyor belt (3) at intervals. A brush roller (10) is rotatably mounted on the storage tank (5). The brush roller (10) is positioned above the discharge conveyor belt (3). Brush bristles (11) are evenly distributed on the brush roller (10), and the brush bristles (11) abut against the workpiece placed on the discharge conveyor belt (3).

2. The hot-dip galvanizing equipment according to claim 1, characterized in that: The storage tank (5) is equipped with a return pipe (8), and the two ends of the return pipe (8) are connected to the storage tank (5) and the rinsing pipe (61) respectively. The return pipe (8) connects the storage tank (5) and the rinsing pipe (61).

3. The hot-dip galvanizing equipment according to claim 1, characterized in that: A linkage mechanism (13) is provided between the brush roller (10) and the rotating disk (91), and the brush roller (10) drives the rotating disk (91) to rotate through the linkage mechanism (13).

4. A hot-dip galvanizing process using the hot-dip galvanizing equipment of claim 3, comprising the following steps: S1: Degreasing, degreasing the workpiece and cleaning the grease from the surface of the workpiece; S2: Pickling, the degreased workpiece is placed in the pickling tank for pickling to remove the oxide layer and rust spots on the surface of the workpiece; S3: Immersion washing, the pickled workpiece is placed in an immersion plating bath (1) with a plating flux solution for immersion washing; S4: Zinc immersion, the workpiece is placed in the immersion plating bath (1) for hot-dip zinc immersion, so that a zinc plating layer is formed on the surface of the workpiece; S5: Cooling, rinsing the workpiece after galvanizing to cool it down; S6: Passivation. The galvanized workpiece is placed in a passivation bath for passivation treatment, so that the surface of the workpiece is covered with a passivation film.

Images