Concave cavity plating compensation tool

Abstract

The utility model belongs to the technical field of brush plating, and relates to a concave cavity plating compensation tool. The cavity coating compensation tool comprises a handle, a metal brush pen base body and a graphite anode which are connected in sequence. The graphite anode is wrapped with a liquid absorption gasket; the graphite anode and the liquid absorption gasket are both in a semi-spherical shape. The performance of a plating layer repaired by the compensation tool is stable and reliable, a good protection effect on parts is achieved, the corrosion resistance of a passive film layer is not less than 96 hours, and the corrosion resistance of the plating layer is not less than 360 hours; after 200 hours of hydrogen embrittlement tensile test, the used brush plating solution does not generate hydrogen embrittlement performance on parts; a binding force test is carried out through an adhesive tape method, the binding force of the plating layer and the substrate is good, and the plating layer separation phenomenon does not occur.

Description

Technical Field

[0001] The utility model belongs to the technical field of electric brush plating and relates to a cavity plating compensation tool. Background Art

[0002] High-strength steel materials are increasingly used in the aviation field. Some parts are large in size and complex in shape. Non-matching surfaces are generally protected by low-hydrogen embrittlement cadmium plating or cadmium-titanium plating. During the electroplating process, low-current areas often appear in the cavity area due to the uneven distribution of power lines, and the resulting coating will be thin or even non-coated. For such local cavity areas, the solution of reworking and re-plating the entire part is not only costly and time-consuming, but also often causes local damage to the part and requires multiple reworks to compensate successfully. However, multiple reworks will also affect the performance of the part.

[0003] Prior art CN105350038B discloses a local electroplating device and a local electroplating method, which are particularly suitable for local electroplating of a workpiece with a through inner hole to be plated, and mainly position the workpiece between the fixed part and the moving part, and at the same time, the fixed part and the moving part are respectively provided with a liquid guide hole connected to the part to be plated, so that the workpiece is set as the cathode, and the anode metal strip is inserted into the liquid guide hole and the electroplating liquid is continuously injected into the liquid guide hole, thereby allowing the cations to flow through the part to be plated with the electroplating liquid and be reduced to a coating to complete the local electroplating; the invention can directly perform local electroplating through the overall structural configuration, without the need for pre-operation to separate the electroplated part from the non-electroplated part, and no subsequent trimming is required after electroplating, which significantly simplifies the process and improves the process efficiency and economic benefits. However, this method is not suitable for local electroplating of the outer surface, and for installed parts, such as field parts performing flight missions, if there is local damage to the concave cavity arc surface, it cannot be applied to the local electroplating of the concave cavity. Utility Model Content

[0004] The utility model aims to provide a cavity plating compensation tool.

[0005] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0006] A concave cavity plating compensation tool comprises a handle, a metal brush pen base and a graphite anode which are connected in sequence; the graphite anode is wrapped with a liquid absorbing gasket; the graphite anode and the liquid absorbing gasket are both in a hemispherical shape.

[0007] By using a hemispherical graphite anode and a liquid absorbing gasket, local brush plating compensation is performed on the thin coating thickness and the uncoated area. The graphite anode and the liquid absorbing gasket can fit tightly with the arc surface of the concave cavity without causing power loss, and can produce a uniform coating in the repaired area.

[0008] In one preferred embodiment, the metal brush pen base and the graphite anode are threadedly connected.

[0009] The hemispherical graphite anode is mainly used for conducting electricity and providing power lines, and is the most important part of the brush plating tool. After installing the graphite anode on the brush plating pen base, it must be firmly clamped to ensure good conductivity.

[0010] In one preferred embodiment, the handle is made of insulating material.

[0011] In one of the preferred embodiments, in order to ensure good conductivity, the surface of the metal brush pen base needs to be polished.

[0012] Use emery cloth to polish off various oxides or corrosion products on the metal brush plating pen substrate before connecting to the graphite anode.

[0013] In one of the preferred embodiments, the liquid absorbent pad is a multi-layer structure.

[0014] In one of the preferred embodiments, the liquid-absorbing pad has a three-layer structure, which includes filter paper, a surface pad and a gauze from the inside to the outside.

[0015] In one preferred embodiment, the face pad is a cotton sponge.

[0016] In the liquid absorbing pad, the filter paper is wrapped on the hemispherical graphite anode to prevent the carbon particles of the anode from accumulating in the plating solution. The loose carbon particles on the surface of the hemispherical graphite anode are cleaned before wrapping. The sponge surface pad mainly plays the role of absorbing and storing the brush plating solution. The surface pad is tightly wrapped on the surface of the hemispherical graphite anode. There should be no bulges and thin spots, let alone any cracks. The gauze mainly plays the role of fixing the surface pad to ensure that the surface pad will not fall off.

[0017] In one preferred embodiment, the angle between the straight line from the uppermost position of the graphite anode to the axis and the straight line from the lowermost position of the graphite anode to the axis is the central angle, and the central angle is 60-120°.

[0018] In one preferred embodiment, the distance from any point of the graphite anode to the axis is the radius, and the radius is 2-5 mm smaller than the diameter of the cavity. If the diameter is too large or too small, the graphite anode cannot fit well with the arc surface of the pit, resulting in uneven brush plating.

[0019] The size of the central angle and the size of the radius of the graphite anode are adjusted according to the size of the pit.

[0020] The beneficial effects of the utility model are:

[0021] The utility model studies the local repair process of the coating in the concave camber surface area of ​​high-strength steel materials, and explores a feasible local coating repair tool and method, which can replace the electroplated cadmium layer or cadmium-titanium layer. During the brush plating process, the electric lines between the hemispherical graphite anode and the concave camber surface are distributed in a "fan-shaped" manner, the distance between the electric lines is basically equal, and the generated coating liquid is uniform. The coating performance after being repaired by the compensation tool of the utility model is stable and reliable, and has a good protective effect on the parts. The corrosion resistance of the passivation film layer is not less than 96h, and the corrosion resistance of the coating is not less than 360h; the brush plating liquid used has been subjected to a 200-hour hydrogen embrittlement tensile test and will not produce hydrogen embrittlement performance on the parts; the bonding force test is carried out by the tape method, and the bonding force between the coating and the substrate is good, and no coating separation occurs; the brush plating tool and method used should be simple and fast to operate, and have strong operability. The tool and method used in the utility model are simple and fast to operate, and can not only realize the local compensation of the coating in the low current density area of ​​the concave cavity of the in-field parts, but also can easily realize the local compensation of the coating in the low current density area of ​​the concave cavity of the out-field parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The structure diagram of the concave cavity coating compensation tool, wherein 1-handle, 2-metal brush pen base, 3-graphite anode, 4-filter paper, 5-surface pad, 6-gauze;

[0023] Figure 2 It is the overall schematic diagram of the cavity plating compensation tool;

[0024] Figure 3 A cross-sectional view of a cavity plating compensation tool;

[0025] Figure 4 Schematic diagram of brush plating trajectory. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the utility model more clear, the embodiments of the utility model will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0027] Example 1

[0028] like Figure 1 As shown, a cavity plating compensation tool comprises a handle 1, a metal brush pen base 2 and a graphite anode 3 connected in sequence; the graphite anode 3 is wrapped with a liquid absorbing gasket; the graphite anode 3 and the liquid absorbing gasket are both hemispherical. The metal brush pen base 2 and the graphite anode 3 are connected by threads. The handle 1 is an insulating material. The liquid absorbing gasket is a three-layer structure, which includes filter paper 4, a surface pad 5 and a gauze 6 from the inside to the outside. The surface pad 5 is a cotton sponge.

[0029] Example 2

[0030] 1. The arc radius R1 of a certain cavity is 120mm, the arc length is 160mm, the thickness of the liquid absorbing gasket is 3mm, and the radius R2 of the graphite anode is determined to be 117mm according to the area of ​​the pit, and the central angle θ is 76.4°.

[0031] 2. Press Figure 1 Prepare the cavity plating compensation tool.

[0032] 3. Calculate the brush plating area that needs compensation

[0033] S 刷镀面积 =RL / 2=120*80 / 2=4800mm 2 =0.48dm 2

[0034] (Where R is the radius of the arc, L is the length of the arc)

[0035] 4. Calculate the amount of electricity required for brush plating

[0036] Q=C*δ*SSPS 5070 brush plating solution power consumption coefficient C is 0.0488A·h / dm 2 ·μm, the coating thickness of brush plating is 10μm, and the area of ​​brush plating is 0.48dm 2 .

[0037] Q=0.0488*10*0.48=0.234A·h

[0038] 5. According to Figure 2 Connect the cavity plating compensation tool to the positive pole of the power supply, and connect the part to the negative pole of the power supply. In this way, during the brush plating process, the part is the cathode, the graphite electrode of the brush plating pen is the anode, and the SPS 5070 brush plating solution is an electrolyte containing metal cadmium ions.

[0039] 6. Before brush plating, pre-treat the pits. The specific process is as follows:

[0040] 1) Organic solvent cleaning: Use acetone for manual cleaning until the oil stains are completely removed.

[0041] 2) Shielding protection: electroplating protective tape or insulating tape.

[0042] 3) Grinding of the area to be compensated: Use 180 mesh or finer water-abrasive sandpaper or aluminum oxide grinding pad to grind the brush-plated area, and grind the transition area to a smooth transition.

[0043] 4) Surface cleaning: Use a clean cloth to clean the dust after grinding.

[0044] 5) Organic solvent cleaning: Use acetone to clean the polished surface.

[0045] 6) Cold water washing: Use a washing bottle to spray deionized water to rinse the polished surface for 1 minute to 2 minutes.

[0046] 7) 30s water film continuity check: Carry out a 30s water film continuity check on the cleaned surface. The surface is qualified if the water film does not break within 30s.

[0047] 8) Brush plating solution cleaning: Use SPS 5070 brush plating cadmium solution to clean the brush plated surface of the parts. The relative moving speed of the anode and cathode is 6m / min~15m / min. The voltage is 14V. The parts are connected to the positive pole of the power supply and the brush plating pen is connected to the negative pole of the power supply.

[0048] Then, the graphite anode wrapped with cotton pad is completely soaked in SPS 5070 brush plating solution, the reverse current button on the power supply is adjusted, the brush pen connection is adjusted to the negative pole, the zero connection is the positive pole, the voltage is adjusted to 14V, and the brush pen is moved at a relative speed of 6m / min to 15m / min to clean the area to be brush plated, and the time is about 3-5s. In this process, the part as the anode is an electrochemical corrosion process, and a fresh brush plating surface can be obtained.

[0049] 7. Adjust the positive and reverse current buttons on the brush plating power supply so that the brush plating pen is connected to the positive pole of the power supply and the parts are connected to the negative pole of the power supply.

[0050] 8. Move the brush pen dipped in the plating liquid on the surface of the plating area for several circles to ensure that all the plating areas are wetted by the plating liquid.

[0051] 9. Turn on the power switch and set the power required for brush plating to 0.234A·h on the brush plating power supply equipment.

[0052] 10. Set the impulse voltage to 20V, and let the brush start plating in the compensation area with an "O"-shaped motion trajectory at a relative moving speed of 15m / min to 36m / min. The schematic diagram of the brush plating trajectory is as follows: Figure 4 As shown. After a visible coating is formed in the brush-plated area, adjust the voltage to 8V-14V immediately and continue brush-plating. During the voltage adjustment process, the brush pen should be separated from the parts.

[0053] 11. The amount of electricity used for brush plating is determined based on the thickness of the coating and the area of ​​brush plating. Therefore, when the electricity alarm sounds a prompt, the power will be cut off immediately and the brush plating will be completed.

[0054] 12. Cold water washing: Use a washing bottle to spray deionized water to rinse the brush-plated surface for 1 minute to 2 minutes.

[0055] 13. Remove shielding protection: Remove shielding and protective materials without any residual foreign matter.

[0056] 14. Polishing transition area: Use aluminum wool to polish the brush-plated transition area or edge to form a uniform transition.

[0057] 14. Cold water washing: Use a washing bottle to spray deionized water to rinse the polished surface for 1 to 2 minutes. If necessary, you can use a rag to wipe and clean.

[0058] 15. Local passivation: Use a cotton cloth dipped in Ultrachromate 300 passivation liquid to gently wipe the brush-plated surface of the concave arc area of ​​the part repeatedly for about 60s to 90s until a passivation film of light golden to dark bronze is formed on the brush-plated surface.

[0059] 16. Cold water washing: Use a washing bottle to spray deionized water to rinse the passivated surface for 1min to 2min.

[0060] 17. Drying: Use clean compressed air with a temperature not exceeding 50°C to dry the passivated surface. If it is inconvenient to use compressed air in the field, you can also wipe it dry gently.

[0061] 18. Coating inspection: Visually inspect the appearance of the brush-plated coating in the compensation area; use a thickness gauge to measure the thickness of the brush-plated coating in the compensation area; use the 3M tape method to measure the bonding strength of the brush-plated coating in the compensation area.

[0062] Tests have shown that the corrosion resistance of the passivation film layer is not less than 96 hours, and the corrosion resistance of the coating is not less than 360 hours; the brush plating solution used has undergone a 200-hour hydrogen embrittlement tensile test and will not cause hydrogen embrittlement to the parts; the bonding strength test was carried out using the tape method, and the bonding strength between the coating and the substrate was good, and no coating separation occurred.

[0063] During the brush plating operation, the electrode surface should be in contact with the compensation surface to be brush plated, and the applied pressure should be minimized to avoid solution loss and excessive wear of the brush plating pen covering.

[0064] Apply the solution to the surface to be plated using a wash bottle, medical cotton wool saturated with the solution, or a natural cotton cloth.

[0065] Before turning on the power supply, the cathode and anode should be in contact with each other in the moistened area to be compensated and start to move relative to each other before turning on the current. The anode is not allowed to remain still on the cathode surface when current is on to avoid burns.

[0066] The brush plating pen performs an "O" shape movement. The direction of movement of the brush plating pen cannot be changed on the compensated area, otherwise burns will occur. The direction of movement can only be changed when the brush plating pen is on the protective area and completely separated from the plated area.

[0067] The brush plating pen should move at a constant speed to ensure uniform distribution of the coating.

[0068] At present, the common brush plating anodes include rod-shaped anodes, plate-shaped anodes, and ring-shaped anodes, which are not effective in treating such pits. Rod-shaped anodes generally have better brush plating effects on local areas in holes. When brush plating on curved surfaces, the contact point between the rod-shaped anode head and the curved surface is small, the brush plating efficiency is too low, and it is not convenient to operate; plate-shaped anodes are generally rectangular or square anodes. This type of anode has the best brush plating effect on flat surfaces. When used on curved surfaces, the local area cannot fit the curved surface, an air layer will be generated, resulting in uneven brush plating, etc.; ring anodes are generally semicircular rings, mainly for brush plating the uniformly sized outer circumference of rod-shaped or cylindrical parts, and cannot be brush plated on the curved surface of concave cavities.

[0069] The brush plating anode used in the utility model is a hemispherical graphite anode, which fully complies with the concept of pictographic design, and the graphite anode used has good conductivity and stable chemical properties, and can be well fitted with the concave cavity surface of brush plating to ensure uniform distribution of electric lines during brush plating.

Claims

1. A cavity plating compensation tool, characterized in that: It comprises a handle, a metal brush pen base and a graphite anode which are connected in sequence; the graphite anode is wrapped with a liquid absorbing gasket; the graphite anode and the liquid absorbing gasket are both in a hemispherical shape; the liquid absorbing gasket is a multi-layer structure; the liquid absorbing gasket is a three-layer structure, which comprises filter paper, a surface pad and a gauze from the inside to the outside.

2. The cavity plating compensation tool according to claim 1, characterized in that: The metal brush pen base and the graphite anode are threadedly connected.

3. The cavity plating compensation tool according to claim 1, characterized in that: The face pad is a cotton sponge.

4. The cavity plating compensation tool according to any one of claims 1 to 3, characterized in that: The angle between the straight line from the uppermost position of the graphite anode to the axis and the straight line from the lowermost position of the graphite anode to the axis is the central angle, and the central angle is 60-120°.

5. The cavity plating compensation tool according to any one of claims 1 to 3, characterized in that: The distance from any point of the graphite anode to the axis is the radius, and the radius is 2-5 mm smaller than the diameter of the cavity.

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