Surface galvanizing process and equipment for rivet nut

Abstract

The invention discloses a process and equipment for galvanizing the surface of a rivet nut, which comprises the following steps: deoiling the surface of the rivet nut by using lime, chaff and charcoal, cleaning by using clear water, pickling by using a mixed solution of hydrochloric acid and a corrosion inhibitor, cleaning again after pickling is completed, adding into an ammonium zinc chloride solution for soaking, and drying to obtain the surface of the rivet nut. According to the method, the rivet nut is subjected to oil removal, then the rivet nut is fed into galvanizing equipment to be galvanized after being dried, the rivet nut is rapidly immersed into normal-temperature water to be subjected to cold quenching after galvanizing is completed, finally, the surface of the rivet nut is passivated, materials used when the surface of the rivet nut is subjected to oil removal are low in corrosivity, and danger in the process is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of nut surface treatment, and particularly relates to a surface galvanizing process and equipment for rivet nuts. Background Art

[0002] In order to improve the corrosion resistance of rivet nuts, it is usually necessary to perform galvanizing operations on the surfaces of rivet nuts. Common galvanizing methods include hot-dip galvanizing and electro-galvanizing, etc.

[0003] Among them, for hot-dip galvanizing, it is necessary to degrease the rivet nuts before galvanizing to remove the grease on the surfaces of the rivet nuts, so that zinc can easily adhere to the surfaces of the rivet nuts.

[0004] In the prior art, alkaline degreasing solutions are usually used for degreasing, but the pH value of the alkaline degreasing solution is generally 12 - 13, with strong alkalinity, and it is easy to cause contact corrosion and injury during the degreasing process, which is relatively dangerous. Summary of the Invention

[0005] In order to solve the deficiencies in the above prior art, the present invention proposes a surface galvanizing process and equipment for rivet nuts.

[0006] In order to achieve the above technical effects, the present invention adopts the following solutions:

[0007] A surface galvanizing process for rivet nuts, comprising:

[0008] S1. Load the rivet nuts into a drum, add quicklime and stir, then add coarse bran and continue stirring, and finally add charcoal and stir. After completion, remove the coarse slag;

[0009] S2. Feed the rivet nuts after removing the coarse slag into a spraying device and continuously spray with clean water at least twice to remove the fine slag on the surfaces of the rivet nuts;

[0010] S3. Then add the sprayed rivet nuts into a mixed solution of hydrochloric acid and a corrosion inhibitor for pickling, and the pickling temperature is 20 - 30°C;

[0011] S4. Feed the pickled rivet nuts into the spraying device again and spray and wash with clean water;

[0012] S5. After spray washing, put the rivet nuts into an ammonium zinc chloride solution and soak at a temperature of 60 - 70°C;

[0013] S6. After the soaked rivet nuts are dried by hot air, add them into a galvanizing device and perform galvanizing in a zinc-aluminum mixed solution at a temperature of 445 - 455°C;

[0014] S7. After galvanizing is completed, immediately feed the rivet nuts into normal-temperature cold water for cooling;

[0015] S8. Immerse the cooled rivet nuts in a silicate passivation solution.

[0016] S9. Dry the passivated rivet nuts.

[0017] In an optimized technical solution, the content of zinc in the zinc-aluminum mixed solution is not less than 98.5%, and the content of aluminum is 0.01 - 0.02%.

[0018] A galvanizing device includes:

[0019] A galvanizing tank, in which a heating component is provided.

[0020] A rotating frame, which is rotatably arranged in the galvanizing tank. The rotating frame is driven to rotate by a first driving mechanism, and a polygonal limiting block overlapping with the rotation center protrudes from the upper end of the rotating frame.

[0021] A galvanizing basket, which can be placed on the upper end of the rotating frame. A number of hollow holes are provided on the side wall of the galvanizing basket, and a limiting groove matching with the polygonal limiting block is opened at the bottom of the galvanizing basket.

[0022] A temporary storage room, which is arranged on the side of the galvanizing tank, and the lower end of the temporary storage room is communicated with the lower end of the galvanizing tank.

[0023] A piston plate, which is arranged to move vertically in the temporary storage room and is driven to move by a second driving mechanism.

[0024] In a preferred technical solution, the first driving mechanism includes a first motor arranged at the lower end of the galvanizing tank, and the output end of the first motor extends into the galvanizing tank and is fixedly connected to the rotation center at the lower end of the rotating frame.

[0025] In a preferred technical solution, a circular chute is provided on the inner wall of the galvanizing tank, and a sliding edge that is embedded in the chute and slides is provided on the edge of the rotating frame.

[0026] In a preferred technical solution, the second driving mechanism includes an electric push rod installed at the upper end of the temporary storage room, and the electric push rod extends into the temporary storage room and is fixedly connected to the piston plate.

[0027] In a preferred technical solution, a cover plate for closing the galvanizing tank is provided on the upper end of the galvanizing tank, and air holes are opened on the cover plate.

[0028] In a preferred technical solution, the heating component includes a number of electric heating tubes.

[0029] In a preferred technical solution, a temperature sensor is provided in the galvanizing tank.

[0030] Compared with the prior art, the beneficial effects are:

[0031] 1. In the present invention, first, lime is brought into contact and mixed with the grease on the surface of the nut. The lime can react with the fatty acids in the grease to form soap. Then, coarse bran is added and mixed continuously. The coarse bran is relatively rough and rubs against the surface of the nut, which will not cause wear to the surface of the nut. Instead, it can cause the soap formed on the surface of the nut to fall off through friction. After that, charcoal is added for adsorption to further promote the soap to fall off from the surface of the bolt, so that the grease on the surface of the nut can be removed. Moreover, the materials used are not highly corrosive, reducing the danger in the process.

[0032] 2. In the present invention, the galvanizing bath is filled with zinc solution. At the beginning, the piston plate moves upward, thereby sucking the zinc solution into the temporary storage chamber for temporary storage until the rotating frame is exposed. After loading the nuts into the galvanizing basket, the galvanizing basket is placed on the rotating frame, and the polygonal limit block is inserted into the limit groove. Then, the piston plate moves downward, squeezing the zinc solution into the galvanizing bath to submerge the galvanizing basket. The temperature of the zinc solution is maintained by the heating component to galvanize the nuts. After galvanizing is completed, the piston plate moves upward again to suck the zinc solution into the temporary storage chamber, exposing the galvanizing basket. The rotating frame rotates to centrifuge the nuts in the galvanizing basket, thereby throwing out the excess zinc solution. After completion, the galvanizing basket is taken out. Through the present invention, after galvanizing in the galvanizing bath, the residual zinc solution after galvanizing can be removed by centrifugation, ensuring the accuracy of the threads of the nuts and avoiding the spillage of the zinc solution during the transfer of the nuts, which is more convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a schematic cross-sectional view of the galvanizing equipment in the present invention.

[0034] Figure 2 is a schematic top view of the rotating frame of the galvanizing equipment in the present invention.

[0035] Reference numerals: 1, galvanizing bath; 2, rotating frame; 3, sliding edge; 4, sliding groove; 5, galvanizing basket; 6, hollow hole; 7, limit groove; 8, polygonal limit block; 9, electric heating tube; 10, first motor; 11, cover plate; 12, air hole; 13, temperature sensor; 14, temporary storage chamber; 15, piston plate; 16, electric push rod. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0037] A surface galvanizing process and equipment for riveted nuts, wherein the galvanizing process includes:

[0038] S1. Load the riveted nuts into a drum, add quicklime and stir, then add coarse bran and continue stirring, and finally add charcoal and stir. After completion, remove the coarse residue;

[0039] S2. The rivet nuts after removing the coarse slag are sent into a spraying device and continuously sprayed with clean water at least twice to remove the fine slag on the surface of the rivet nuts.

[0040] S3. Then the sprayed rivet nuts are added into a mixed solution of hydrochloric acid and an inhibitor for pickling, and the pickling temperature is 20 - 30 °C.

[0041] S4. The pickled rivet nuts are sent into the spraying device again and sprayed and cleaned with clean water.

[0042] S5. After spraying and cleaning, the rivet nuts are put into a zinc ammonium chloride solution and soaked at a temperature of 60 - 70 °C.

[0043] S6. After the soaked rivet nuts are dried by hot air, they are added into a galvanizing device and galvanized in a zinc - aluminum mixed solution at a temperature of 445 - 455 °C.

[0044] S7. After galvanizing is completed, the rivet nuts are immediately sent into normal - temperature cold water for cooling.

[0045] S8. The cooled rivet nuts are soaked in a silicate passivation solution.

[0046] S9. The passivated rivet nuts are dried.

[0047] In the above process, first, lime is contacted and mixed with the grease on the surface of the nut. Lime can react with the fatty acid in the grease to form soap. Then, coarse bran is added and mixed continuously. The coarse bran is relatively rough. The coarse bran rubs against the surface of the nut, which will not cause wear to the surface of the nut. Moreover, through friction, the soap formed on the surface of the nut can be shed. Then, by adding charcoal for adsorption, it further promotes the shedding of the soap from the surface of the bolt, so that the grease on the surface of the nut can be removed. And the materials used are not highly corrosive, reducing the danger in the process.

[0048] In addition, soaking in zinc ammonium chloride forms a protective film on the surface of the nut to prevent secondary oxidation, and hot - air drying after soaking thoroughly removes moisture, avoiding splashing of the zinc - aluminum solution during subsequent galvanizing.

[0049] In an optimized technical solution, the content of zinc in the zinc - aluminum mixed solution is not less than 98.5%, and the content of aluminum is 0.01 - 0.02%.

[0050] The galvanizing device includes: a galvanizing tank 1, a rotating frame 2, a galvanizing basket 5, a temporary storage room 14, and a piston plate 15.

[0051] A heating component is provided in the galvanizing tank 1. The galvanizing tank 1 is filled with zinc liquid, and the heating component is used to maintain the temperature of the zinc liquid.

[0052] The rotating frame 2 is rotatably arranged in the galvanizing bath 1. The rotating frame 2 is driven to rotate by a first driving mechanism. The upper end of the rotating frame 2 protrudes with a polygonal limiting block 8 overlapping with the rotation center. A through hole for the zinc liquid to pass through is vertically penetrated through the rotating frame 2.

[0053] The galvanizing basket 5 can be placed on the upper end of the rotating frame 2 and can be removed from the rotating frame 2, which is used to lift the galvanizing basket 5 out of the galvanizing bath 1 to install nuts or pour out nuts. A plurality of hollow holes 6 are provided on the side wall of the galvanizing basket 5 to facilitate the entry and ejection of the zinc liquid. A limiting groove 7 matching with the polygonal limiting block 8 is opened at the bottom of the galvanizing basket 5. Through the cooperation of the limiting groove 7 and the polygonal limiting block 8, the rotating frame 2 can drive the galvanizing basket 5 to rotate.

[0054] The temporary storage chamber 14 is arranged on the side of the galvanizing bath 1, and the lower end of the temporary storage chamber 14 is communicated with the lower end of the galvanizing bath 1.

[0055] The piston plate 15 is arranged to move vertically in the temporary storage chamber 14 and is driven to move by a second driving mechanism.

[0056] The galvanizing bath 1 is filled with zinc liquid. At the beginning, the piston plate 15 moves upward, and the zinc liquid is sucked from the galvanizing bath 1 into the temporary storage chamber 14 for temporary storage through negative pressure until the rotating frame 2 is exposed. After the nuts are loaded into the galvanizing basket 5, the galvanizing basket 5 is placed on the rotating frame 2, and the polygonal limiting block 8 is inserted into the limiting groove 7. Usually, when the positions of the polygonal limiting block 8 and the limiting groove 7 cannot be observed, the galvanizing basket 5 is placed on the rotating frame 2 and shaken left and right, and the rotating frame 2 is rotated. When the polygonal limiting block 8 and the limiting groove 7 overlap, the polygonal limiting block 8 naturally snaps into the limiting groove 7. Then the piston plate 15 moves downward, squeezing the zinc liquid into the galvanizing bath 1 to submerge the galvanizing basket 5. The temperature of the zinc liquid is maintained by the heating component to galvanize the nuts. After the galvanizing is completed, the piston plate 15 moves upward again to suck the zinc liquid into the temporary storage chamber 14, exposing the galvanizing basket 5. The rotating frame 2 rotates rapidly to centrifuge the nuts in the galvanizing basket 5, so as to eject the excess zinc liquid. After completion, the galvanizing basket 5 is taken out. Through the present invention, after galvanizing in the galvanizing bath 1, the residual zinc liquid after galvanizing can be removed by centrifugation, which ensures the accuracy of the nut threads and avoids the spillage of zinc liquid during the transfer of nuts, making it more convenient.

[0057] In a preferred technical solution, the first driving mechanism includes a first motor 10 arranged at the lower end of the galvanizing bath 1. The output end of the first motor 10 extends into the galvanizing bath 1 and is fixedly connected to the rotation center at the lower end of the rotating frame 2. The rotating frame 2 is driven to rotate by the first motor 10.

[0058] Preferred technical solution: A circular chute 4 is provided on the inner wall of the galvanizing tank 1, and a sliding edge 3 that is inserted into and slides in the chute 4 is provided on the edge of the rotating frame 2. Thus, the rotating frame 2 is supported on the inner wall of the galvanizing tank 1 and rotates.

[0059] Preferred technical solution: The second driving mechanism includes an electric push rod 16 installed at the upper end of the temporary storage chamber 14, and the electric push rod 16 extends into the temporary storage chamber 14 and is fixedly connected to the piston plate 15. The piston plate 15 is driven to move vertically by the electric push rod 16.

[0060] Preferred technical solution: A cover plate 11 for closing the galvanizing tank 1 is provided on the upper end of the galvanizing tank 1, and an air hole 12 is opened on the cover plate 11. The cover plate 11 is arranged on the upper end of the galvanizing tank 1 to prevent zinc liquid from splashing when the rotating frame 2 drives the galvanizing basket 5 to rotate.

[0061] Preferred technical solution: The heating assembly includes a plurality of electric heating tubes 9.

[0062] Preferred technical solution: A temperature sensor 13 is provided in the galvanizing tank 1.

[0063] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0064] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0065] All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A surface galvanizing process for rivet nuts, characterized in that: include: S1. Put the rivet nut into the drum, add quicklime and stir, then add bran and continue stirring, finally add charcoal and stir, and remove the coarse residue after completion; S2. After the coarse slag is removed, the rivet nut is sent to a spraying device and sprayed with clean water continuously for at least two times to remove the fine slag on the surface of the rivet nut; S3, then add the sprayed rivet nuts into a mixed solution of hydrochloric acid and corrosion inhibitor for pickling, the pickling temperature is 20-30°C; S4. The pickled rivet nuts are sent to the spraying device again and sprayed with clean water for cleaning; S5. After spray cleaning, put the rivet nut into zinc ammonium chloride solution and soak it at 60-70℃; S6. After being soaked, the rivet nuts are dried with hot air and then added to the galvanizing equipment for galvanizing in a zinc-aluminum mixed solution at a temperature of 445-455°C; S7. After galvanizing is completed, immediately put the rivet nut into cold water at room temperature for cooling; S8. Soak the cooled rivet nut in silicate passivation solution; S9. Dry the passivated rivet nuts.

2. The surface galvanizing process of the rivet nut according to claim 1, characterized in that: The zinc content in the zinc-aluminum mixed solution is not less than 98.5%, and the aluminum content is 0.01-0.02%.

3. A galvanizing equipment as claimed in claim 1, characterized in that: include: A galvanizing pool (1), wherein a heating component is provided in the galvanizing pool (1); A rotating frame (2), the rotating frame (2) being rotatably disposed in the galvanizing pool (1), the rotating frame (2) being driven to rotate by a first driving mechanism, and a polygonal limit block (8) overlapping with the rotation center being protruded from the upper end of the rotating frame (2); A galvanized basket (5), the galvanized basket (5) can be placed on the upper end of the rotating frame (2), a plurality of hollow holes (6) are provided on the side wall of the galvanized basket (5), and a limiting groove (7) is provided at the bottom of the galvanized basket (5) to cooperate with a polygonal limiting block (8); A temporary storage room (14), wherein the temporary storage room (14) is arranged on the side of the galvanizing pool (1), and the lower end of the temporary storage room (14) is connected to the lower end of the galvanizing pool (1); A piston plate (15) is matched and arranged in the temporary storage chamber (14) to move vertically, and the piston plate (15) is driven to move by a second driving mechanism.

4. The galvanizing equipment according to claim 1, characterized in that: The first driving mechanism comprises a first motor (10) arranged at the lower end of the galvanizing pool (1), wherein the output end of the first motor (10) extends into the galvanizing pool (1) and is fixedly connected to the rotation center at the lower end of the rotating frame (2).

5. The galvanizing equipment according to claim 1, characterized in that: The inner wall of the galvanizing pool (1) is provided with a ring-shaped sliding groove (4), and the edge of the rotating frame (2) is provided with a sliding edge (3) embedded in the sliding groove (4) for sliding.

6. The galvanizing equipment according to claim 1, characterized in that: The second driving mechanism comprises an electric push rod (16) mounted on the upper end of the temporary storage chamber (14); the electric push rod (16) extends into the temporary storage chamber (14) and is fixedly connected to the piston plate (15).

7. The galvanizing equipment according to claim 1, characterized in that: The upper end cover of the galvanizing pool (1) is provided with a cover plate (11) for closing the galvanizing pool (1), and the cover plate (11) is provided with air holes (12).

8. The galvanizing equipment according to claim 1, characterized in that: The heating component comprises a plurality of electric heating tubes (9).

9. The galvanizing equipment according to claim 1, characterized in that: A temperature sensor (13) is provided in the galvanizing pool (1).

Images