Aluminum pipe painting detection equipment, detection method thereof and conductive liquid for detection

Abstract

The invention discloses aluminum pipe inner coating detection equipment, a detection method thereof and conductive liquid for detection, and the detection method comprises the following steps: filling the conductive liquid into an aluminum pipe of which the inner wall is provided with an inner coating, electrifying between the conductive liquid and the outer surface of the aluminum pipe, and measuring the actual current value of an electrified circuit; when the default inner coating is in a complete state, the default current value measured according to the measurement mode is A0, and when the actual current value is larger than the default current value, it is judged that the inner coating is abraded or the thickness does not reach the standard. Conductive liquid is filled into an inner cavity of an aluminum pipe, meanwhile, by means of the structural characteristics that a pipe nozzle of the aluminum pipe faces downwards and is exposed (not painted), the pipe nozzle is connected to a lower electrode, an upper electrode is inserted into the conductive liquid from the tail of the aluminum pipe, namely, resistance is formed between a pipe body and the conductive liquid, and the larger the resistance is, the lower the current value is, otherwise, the higher the current value is. Therefore, the coverage of the inner coating of the inner cavity of the aluminum tube is judged.

Description

Technical Field

[0001] The present invention relates to a quality inspection device and method for aluminum hoses for packaging, in particular to an aluminum hose inner coating inspection device and a detection method thereof and a conductive liquid for the detection. Background Art

[0002] The production process of aluminum hoses (aluminum tubes) generally includes the following steps: forming, heat treatment, internal spraying, baking, external spraying (or painting), baking, and covering; among them, the quality of the inner coating is related to the quality of the aluminum tube. Once the inner coating is worn, the contents of the aluminum tube will come into contact with the aluminum material, which is easy to corrode the aluminum tube.

[0003] In the production process of the above-mentioned aluminum tube, the quality of the inner coating is generally affected in two steps. The first is the process of internal spraying, and the spraying process will affect the uniformity of the spraying; the second is the process of internal spraying. Figure 5 and Figure 6 As shown, during exterior painting, the aluminum tube 1 is enclosed within a rotating shaft 6 and driven to rotate by it (specifically, the aluminum tube processing equipment is equipped with a turntable 7 that rotates in the direction of the arrow R1, gradually rotating each workstation to the painting area; the turntable is equipped with a rotating shaft 6 corresponding to each workstation, which drives the enclosed aluminum tube to rotate in the direction of the arrow R2). Dirt, scratches, or idling with the aluminum tube can cause varying degrees of wear on the inner coating 13. Existing methods for inspecting inner coatings primarily rely on observation. Because the inner paint layer is dark yellow (light brown), the uncoated aluminum tube is silver-gray. The difference between thick and thin coatings is that a thick coating is darker, while a thinner coating is lighter. By randomly breaking open the aluminum tube and observing the inner coating color, the uniformity of the coating can be determined. Any transition between light and dark indicates uneven coating. However, this inspection method is prone to misjudgment. Furthermore, if the coating quality deteriorates due to the second cause, observation can easily miss the location of wear. Summary of the Invention

[0004] The first object of the present invention is to provide an aluminum tube paint detection device with a simple and reasonable structure and easy use.

[0005] The first object of the present invention is achieved in this way: A device for inspecting the paint coating of an aluminum tube comprises an aluminum tube mounting platform for fixing an inverted aluminum tube. The aluminum tube mounting platform is provided with a lower electrode and an upper electrode. The lower electrode is used for conductive contact with the nozzle of the aluminum tube. The upper electrode cooperates with the aluminum tube mounting platform for lifting and lowering and is used for extending from the tail end of the aluminum tube into the inner cavity of the aluminum tube. A current detection device supplies power to the lower electrode and the upper electrode, detects the current flowing between the lower electrode and the upper electrode, and provides feedback.

[0006] The purpose of the present invention can also be solved by the following technical measures: As a more specific solution, the aluminum tube mounting platform includes a base, a socket, a vertical pole and a plug. The socket and the vertical pole are fixed on the base. The top surface of the socket is provided with a groove corresponding to the tube head of the aluminum tube, and the lower electrode is arranged at the bottom of the groove; a cross bar is provided on the vertical pole, and the plug is located below the cross bar and directly opposite the socket. The upper end of the plug is movably coordinated with the cross bar through a lifting rod, and the upper electrode is arranged at the bottom of the plug.

[0007] As a further solution, the upper electrode is a silver electrode.

[0008] As a further solution, a cavity is provided at the bottom of the groove corresponding to the nozzle of the aluminum tube, the lower electrode is arranged in the cavity, and a spring is provided between the bottom of the lower electrode and the cavity.

[0009] As a further solution, the aluminum tube includes a tube body and a tube head, one end of the tube body is open to form the tail of the aluminum tube, and the tube head includes a tube shoulder and a tube nozzle, the tube nozzle is closed and connected to the other end of the tube body through the tube shoulder; the inner wall of the aluminum tube is provided with an inner coating, or the inner wall of the aluminum tube and the outer wall of the tube body are provided with an inner coating and an outer coating respectively, and the aluminum surface of the tube nozzle is exposed; during testing, a conductive liquid is filled inside the aluminum tube, the upper electrode is in contact with the conductive liquid, and the tube nozzle is in contact with the lower electrode.

[0010] As a further solution, the current detection device includes a DC power supply circuit and a current detection circuit. The DC power supply circuit supplies power to the lower electrode and the upper electrode. The current detection circuit is connected in series with the upper electrode or the lower electrode. The current detection circuit can feedback the current value.

[0011] A second object of the present invention is to provide a method for detecting aluminum tube paint that is simple to operate and reliable.

[0012] The second object of the present invention is achieved in this way: A method for detecting aluminum tube paint coatings comprises: filling a conductive liquid into an aluminum tube having an inner coating on its inner wall, passing electricity between the conductive liquid and the outer surface of the aluminum tube, and measuring the actual current value of the energized circuit; assuming the inner coating is intact, the default current value measured according to the above measurement method is A0; when the actual current value is greater than the default current value, it is determined that the inner coating is worn or the thickness does not meet the standard.

[0013] As a further solution, the conductive liquid is made of copper sulfate, aerosol, glacial acetic acid and distilled water. When the inner coating is worn and the aluminum material is exposed, a short circuit is formed and the actual current value increases significantly. In addition, when the aluminum tube is cut open, it can be seen that the conductive liquid attached to the worn position changes color, so that the corresponding position where the inner coating is worn caused by the processing equipment can be found through the wear position of the inner coating of the aluminum tube.

[0014] As a further solution, the aerosol is silicon dioxide aerosol; the conductive liquid is filled into the inner cavity of the aluminum tube, and the power-on test is performed after 5 seconds.

[0015] A third object of the present invention is to provide a safe and reliable conductive liquid for detection.

[0016] The third object of the present invention is achieved by: A conductive liquid for detection is prepared by mixing 50 g of copper sulfate, 0.25 g of silicon dioxide aerosol, 2.5 g of glacial acetic acid and 5 kg of distilled water.

[0017] The beneficial effects of the present invention are as follows: (1) The present invention fixes the inverted aluminum tube by an aluminum tube mounting stand, making it easy to fill the inner cavity of the aluminum tube with conductive liquid. At the same time, with the structural characteristics of the aluminum tube nozzle facing downward and exposed (not painted), the nozzle is supported on the lower electrode, and the upper electrode moves up and down, making it easy for the upper electrode to be inserted into the conductive liquid from the tail of the aluminum tube, that is, a resistance is formed between the tube body and the conductive liquid. The better the inner coating of the inner cavity of the aluminum tube protects the material of the inner surface of the tube body, the better the quality. At the same time, the greater the resistance, the smaller the current value measured by the current detection device. Conversely, when the inner coating is thin or damaged, the current value measured by the current detection device increases, thereby detecting the quality of the inner coating.

[0018] (2) The present invention uses a prepared conductive liquid with uniform conductivity to avoid adverse effects on detection and improve accuracy.

[0019] (3) The conductive liquid of the present invention produces a chemical reaction when it contacts the aluminum material, so that copper adheres to the surface of the aluminum material, which makes it easier for inspectors to know the location of the inner coating wear after cutting open the aluminum tube, and to find the parts of the aluminum tube processing equipment that cause wear and tear and repair them. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a structural diagram of an embodiment of the present invention.

[0021] Figure 2 for Figure 1 Enlarged structural diagram at point B in the middle.

[0022] Figure 3 This is a schematic structural diagram of an embodiment of the aluminum tube in the present invention.

[0023] Figure 4 This is a schematic diagram of the structure after the upper electrode of the present invention is extended into the aluminum tube.

[0024] Figure 5 This is another embodiment of the aluminum tube in the present invention and a schematic diagram of its structure after being sleeved with a core rod.

[0025] Figure 6This is a schematic diagram of the turntable mechanism in the external coating painting mechanism of aluminum tube processing equipment. DETAILED DESCRIPTION

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments: See also Figures 1 to 6 As shown, an aluminum tube paint inspection device includes an aluminum tube mounting platform 2 for fixing an inverted aluminum tube 1. The aluminum tube mounting platform 2 is provided with a lower electrode 32 and an upper electrode 41. The lower electrode 32 is configured to electrically contact the nozzle 12 of the aluminum tube 1. The upper electrode 41 is movable in a lifting manner with the aluminum tube mounting platform 2 and is configured to extend from the rear end of the aluminum tube 1 into the inner cavity 11 of the aluminum tube 1. A current detection device 5 is configured to supply power to the lower electrode 32 and the upper electrode 41, detect the current flowing between the lower electrode 32 and the upper electrode 41, and provide feedback.

[0028] The aluminum tube mounting platform 2 includes a base 21, a socket 3, a vertical rod 22, and a plug 25. The socket 3 and vertical rod 22 are fixed to the base 21. The top surface of the socket 3 is provided with a groove 34 corresponding to the tube head of the aluminum tube 1, and the lower electrode 32 is disposed at the bottom of the groove 34. The vertical rod 22 is provided with a crossbar 23, and the plug 25 is located below the crossbar 23 and directly opposite the socket 3. The upper end of the plug 25 is movably engaged with the crossbar 23 via a lifting rod 4. The upper electrode 41 is disposed at the bottom of the plug 25. The socket 3 is made of rubber material and can be tightly fitted with the tube head of the aluminum tube 1.

[0029] The upper electrode 41 is a silver electrode. Silver has good stability and is thus prevented from being electrolyzed when in contact with the conductive liquid.

[0030] The bottom of the groove 34 is also provided with a cavity 31 corresponding to the nozzle 12 of the aluminum tube 1 . The lower electrode 32 is disposed in the cavity 31 . A spring 33 is provided between the bottom of the lower electrode 32 and the cavity 31 .

[0031] The aluminum tube 1 comprises a tube body and a tube head. One end of the tube body is open, forming the tail of the tube 1. The tube head comprises a tube shoulder and a nozzle 12. The nozzle 12 is sealed and connected to the other end of the tube body via the tube shoulder. The inner wall of the aluminum tube 1 is provided with an inner coating 13, and the aluminum surface of the nozzle 12 is exposed. During testing, the aluminum tube 1 is filled with a conductive liquid A, the upper electrode 41 contacts the conductive liquid A, and the nozzle 12 contacts the lower electrode 32. The conductive liquid A is prepared by mixing 50g of copper sulfate, 0.25g of silica aerosol, 2.5g of glacial acetic acid, and 5kg of distilled water. The copper sulfate 50g mixed with water produces a light blue color, making it easily recognizable. Furthermore, it contains copper ions, which are conductive. Furthermore, upon contact with aluminum, a chemical reaction occurs, depositing copper on the aluminum surface, making it easier to determine where the inner coating of the aluminum tube 1 is worn. The distilled water used for mixing is relatively pure and free of extraneous conductive ions, resulting in uniform conductive properties across the entire conductive liquid A. A trace amount of silica aerosol mixed with copper sulfate creates a conductive liquid with mild polishing properties. This can selectively corrode the aluminum at extremely small points of inner coating wear (13 points), causing a rapid conductive reaction and preventing missed detection. Glacial acetic acid reacts with copper sulfate to produce copper acetate, which promotes copper deposition, allowing the precipitated copper to better settle on the aluminum at the inner coating wear site, making it easier to detect.

[0032] The current detection device 5 is a prior art device, which generally includes a DC power supply circuit and a current detection circuit. The DC power supply circuit supplies power to the lower electrode 32 and the upper electrode 41. The current detection circuit is connected in series with the upper electrode 41 or the lower electrode 32. The current detection circuit can feedback the current value.

[0033] The DC power supply circuit includes a step-down coil, a rectifier bridge stack and a filter capacitor.

[0034] The current detection device further includes a voltage detection circuit electrically connected between the upper electrode 41 and the lower electrode 32. The current detection circuit and the voltage detection circuit are provided with a current digital display screen 531 and a voltage digital display screen 521 respectively.

[0035] The current detection device 5 provides a 5V DC power supply through a DC power supply circuit 51. The positive (+) pole of the DC power supply is electrically connected to the upper electrode 41 through the current detection circuit, and the negative (-) pole of the DC power supply is electrically connected to the lower electrode 32. The voltage detection circuit is electrically connected between the upper electrode 41 and the lower electrode 32.

[0036] The detection principle is as follows: an aluminum tube 1 having an inner coating 13 on the inner wall of an inner cavity 11 is inserted upside down into a groove 34 of a socket 3, with the nozzle 12 in conductive contact with the lower electrode 32; a conductive liquid A is introduced into the inner cavity 11, and the plug 25 is pulled down to the tail end of the aluminum tube 1, with the upper electrode 41 inserted into the conductive liquid A. The current detection device 5 is activated to allow electricity to flow between the conductive liquid A and the outer surface of the aluminum tube 1, and the actual current value of the energized circuit is measured, which is fed back to the current digital display 531.

[0037] Combined with the conductivity of the aluminum tube and the resistance of the inner coating (calculated based on the inner coating thickness of qualified products), a current range value (A0) after a standard part is energized in the above manner is set as a reference standard. When the actual current value is higher than A0, it is judged that the inner coating 13 does not meet the standard (indicating that the thickness of the inner coating is uneven or worn); when the actual current value is lower than A0, it is judged that the inner coating 13 is too thick, or the electrode has poor contact. In addition, combined with Figure 6 As shown, when the aluminum tube 1 being tested is provided with an outer coating 14, the inner coating 13 is more or less worn due to the nesting of the aluminum tube 1 and the rotating shaft core 6 and the outer painting process. Therefore, when testing aluminum tubes with both inner and outer coatings, the current range value A0 of the reference standard needs to be appropriately increased.

[0038] The current detection device 5 may have an alarm function, and a reference current value A0 is pre-set. When the actual current value is higher or lower than A0, an alarm is given through an indicator light and / or a buzzer. This type of circuit also belongs to the prior art. The present technical solution is to combine this method with the aluminum tube mounting platform 2 for inner coating quality detection.

[0039] The above is a preferred embodiment of the present invention, which shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements are intended to fall within the scope of the present invention as claimed, which is defined by the appended claims and their equivalents.

Claims

1. An aluminum tube paint detection device, characterized in that: It includes an aluminum tube mounting platform, which is used to fix the inverted aluminum tube. The aluminum tube mounting platform is provided with a lower electrode and an upper electrode. The lower electrode is used to be in conductive contact with the nozzle of the aluminum tube. The upper electrode is coordinated with the aluminum tube mounting platform for lifting and lowering, and is used to extend from the tail of the aluminum tube into the inner cavity of the aluminum tube. The current detection device supplies power to the lower electrode and the upper electrode, detects the current flowing between the lower electrode and the upper electrode, and provides feedback.

2. The aluminum tube paint detection equipment according to claim 1 is characterized in that: The aluminum tube mounting platform comprises a base, a socket, a vertical pole and a plug. The socket and the vertical pole are fixed on the base. A groove is provided on the top surface of the socket corresponding to the tube head of the aluminum tube, and the lower electrode is arranged at the bottom of the groove. A cross bar is provided on the vertical pole, and the plug is located below the cross bar and directly opposite to the socket. The upper end of the plug is movably matched with the cross bar through a lifting rod, and the upper electrode is arranged at the bottom of the plug.

3. The aluminum tube paint detection equipment according to claim 1 is characterized in that: The upper electrode is a silver electrode.

4. The aluminum tube paint detection equipment according to claim 2 is characterized in that: The bottom of the groove is also provided with a concave cavity corresponding to the nozzle of the aluminum tube, the lower electrode is arranged in the concave cavity, and a spring is arranged between the bottom of the lower electrode and the concave cavity.

5. The aluminum tube paint detection equipment according to claim 1 is characterized in that: The aluminum tube includes a tube body and a tube head, one end of the tube body is open to form the tail of the aluminum tube, the tube head includes a tube shoulder and a tube nozzle, the tube nozzle is closed and connected to the other end of the tube body through the tube shoulder; the inner wall of the aluminum tube is provided with an inner coating, or the inner wall of the aluminum tube and the outer wall of the tube body are provided with an inner coating and an outer coating respectively, and the aluminum surface of the tube nozzle is exposed; during detection, a conductive liquid is filled inside the aluminum tube, the upper electrode is in contact with the conductive liquid, and the tube nozzle is in contact with the lower electrode.

6. The aluminum tube paint detection equipment according to claim 1 is characterized in that: The current detection device comprises a DC power supply circuit and a current detection circuit. The DC power supply circuit supplies power to the lower electrode and the upper electrode. The current detection circuit is connected in series with the upper electrode or the lower electrode. The current detection circuit can feed back a current value.

7. A method for detecting aluminum tube paint, characterized in that: A conductive liquid is filled into an aluminum tube with an inner coating on the inner wall, and electricity is passed between the conductive liquid and the outer surface of the aluminum tube, and the actual current value of the power circuit is measured; when the default inner coating is in an intact state, the default current value measured according to the above measurement method is A0. When the actual current value is greater than the default current value, it is judged that the inner coating is worn or the thickness does not meet the standard.

8. The aluminum tube paint detection method according to claim 7, characterized in that: The conductive liquid is made of copper sulfate, aerosol, glacial acetic acid and distilled water. When the inner coating is worn and the aluminum material is exposed, a short circuit is formed and the actual current value increases significantly. In addition, when the aluminum tube is cut open, it can be seen that the conductive liquid attached to the worn position changes color, so that the corresponding position where the inner coating is worn caused by the processing equipment can be found through the wear position of the inner coating of the aluminum tube.

9. The aluminum tube paint detection method according to claim 8, characterized in that: The aerosol is silicon dioxide aerosol; the conductive liquid is filled into the inner cavity of the aluminum tube, and the power-on detection is performed after 5 seconds.

10. A conductive liquid for detection, characterized in that: The conductive liquid is blended according to the proportion of 50 g of copper sulfate, 0.25 g of silicon dioxide aerosol, 2.5 g of glacial acetic acid, and 5 kg of distilled water.

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