Appearance treatment process of film capacitor for rail transit

Abstract

The invention discloses an appearance treatment process of a film capacitor for rail transit. The appearance treatment process comprises the following procedures of preparation, shot blasting preparation, first shot blasting, second shot blasting, inspection, appearance treatment and unloading. The time for each step is defined. The method is suitable for appearance treatment of the rail transit thin film capacitor with the stainless steel shell, the appearance of the thin film capacitor can be effectively made attractive, the corrosion resistance can be effectively improved, and the production efficiency of products is improved.

Description

Technical Field

[0001] The present invention relates to the field of capacitor manufacturing, and particularly to an appearance treatment process for thin film capacitors used in rail transit. Background Art

[0002] Thin film capacitors are the core components of converters used in rail transit. The functions of such thin film capacitors are: to provide voltage support for the converters used in rail transit, and at the same time to suppress harmonics on the DC side and buffer the energy exchange between the AC side and the DC side; the process of its energy exchange is relatively complex, and both too large and too small capacitance will affect the control accuracy, and the magnitude of the DC voltage fluctuation also affects the volume and cost of the converters used in rail transit.

[0003] At present, thin film capacitors used in rail transit include two types: oil-immersed capacitors and dry-type capacitors. Among them, the oil-immersed capacitor is composed of a stainless steel box shell, a box cover, an insulator, a guide rod, a core, and impregnated vegetable oil or silicone oil; the dry-type capacitor is composed of a stainless steel box shell, a box cover, an insulator, a guide rod, a core, and cast resin, etc. The weight of such capacitors is in the range of 10 - 40 kg. More and more thin film capacitors are exported to foreign markets together with the whole locomotive or high-speed rail vehicle.

[0004] The box shell and box cover of the thin film capacitor are both made of stainless steel material, and need to be welded by special tools to make them sealed. In addition, there are many production processes for capacitors, and it is inevitable to have marks of surface bumps and scratches on the capacitor box shell during the production process. The welds and the marks of bumps and scratches, etc. need to be subjected to appearance treatment. Usually, the appearance of such capacitors is treated by spraying paint, so that the appearance of the capacitor becomes beautiful, and the surface corrosion resistance of the capacitor box shell also becomes stronger. However, such a treatment method does not meet the environmental protection policies and export requirements of relevant government departments.

[0005] In the appearance treatment methods of metals, passivation is also a commonly used process method. But in this method, it is necessary to wash the capacitor with water, and there are processes for waste water recovery and discharge, thus increasing the production cost. Therefore, it is very necessary to have other appearance treatment process methods to replace the paint process to ensure the beautiful appearance and corrosion resistance of the thin film capacitor. Summary of the Invention

[0006] In order to solve the above problems, the present invention provides an appearance treatment process for a thin film capacitor used in rail transit (hereinafter referred to as "capacitor" for short).

[0007] The technical solution adopted by the present invention is as follows.

[0008] The appearance treatment process method for the capacitor includes the following processes: (1) Preparation: Cover each capacitor insulator with a cover; Add stainless steel shot with a diameter of Φ0.3 - 0.5mm, 400kg, to the shot blasting machine at one time, and add an appropriate amount of shot regularly. (2) Shot Blasting Preparation: Hang the capacitors on the hanging rack by the lifting equipment, and blast two capacitors at a time; Start the dust collection device and the power supply of the shot blasting machine. The inlet and outlet of the shot blasting machine are V-shaped hanging rack tracks. The capacitors to be blasted are sent to the door of the shot blasting machine through the V-shaped track. (3) First Shot Blasting: Set the shot blasting time to 15 minutes, the rotational speed of the shot blasting variable frequency motor to 2850 rpm, the frequency to 50 Hz, and the shot velocity to 64 m / s; The shot blasting machine automatically opens the inlet and outlet doors. The left hanging rack of the capacitor automatically enters the shot blasting chamber, and the inlet and outlet doors are closed. The right hanging rack is loaded with the capacitor for preparation; The shot blasting machine works according to the shot blasting time and the speed of the shot blasting motor. The hanging rack of the capacitor rotates 360 degrees in the shot blasting chamber; After the shot blasting machine finishes working, it automatically opens the inlet and outlet doors. The left hanging rack with the capacitor exits to the original position through the V-shaped hanging rack track, and the dust on the surface of the capacitor and the shot embedded in the weld are removed with compressed air or a brush. (3) Second Shot Blasting: The right hanging rack (already loaded with the capacitor) automatically enters the shot blasting machine; Set the shot blasting time to 15 minutes, the rotational speed of the shot blasting variable frequency motor to 2850 rpm, the frequency to 50 Hz, and the shot velocity to 64 m / s; The shot blasting machine works according to the shot blasting time and the speed of the shot blasting motor. The hanging rack of the capacitor rotates 360 degrees in the shot blasting chamber; After the shot blasting machine finishes working, it automatically opens the inlet and outlet doors; The shot blasting of the capacitor is completed and it is loaded onto a trolley and sent to the next process. (4) Inspection: The surface color of the capacitor case is silver - gray; The shot blasting roughness on the surface of the case is uniform, and there is no phenomenon of missed shot blasting; No scratches, spots, or fingerprints should be observed on the surface of the case after shot blasting; The color of the weld and the mounting bracket of the case has no obvious difference from that of the case; There is no dust and residual shot on the surface of the capacitor. (5) Appearance Treatment: Hang the capacitor on the special production line, and coat the entire surface of the capacitor with high - strength stainless steel protective film liquid, and it can only be taken off the line after natural drying for at least 4 hours. (6) Unloading: Load the capacitor onto a trolley and enter the packaging and warehousing process.

[0009] Among them, the deviation of each of the above - mentioned times can be within ±5%.

[0010] Furthermore, by repeating steps (2) - (5) of the above process, the appearance treatment of multiple capacitors can be carried out.

[0011] Furthermore, when the operator takes the capacitor off the line and transports it, gloves must be worn, and when using a fixture to transport the case, it must not touch oil stains or water spots.

[0012] Furthermore, when transporting the capacitor, it is strictly forbidden to touch the case with hands to avoid bruising or scratching the surface of the case.

[0013] The beneficial effects of the present invention are as follows: According to the structural characteristics of the stainless steel housing of the thin film capacitor for rail transit, by adopting the above method, the appearance of the thin film capacitor can be effectively made beautiful, the corrosion resistance can be increased, and the production efficiency of the product can be improved. Specific embodiments

[0014] The following specific embodiments further illustrate the present invention. This process includes the following procedures: (1) Preparation: Cover each capacitor insulator with a cover; The primary addition amount of stainless steel shot is Φ0.3~0.5mm, 400kg, add it to the shot blasting machine, and add an appropriate amount of shot at regular intervals; (2) Shot blasting preparation: Hang the capacitor on the hanging bracket by the hoisting equipment, and shot blast two capacitors at a time; Start the dust collection device and the power supply of the shot blasting machine. The V-shaped hanging bracket track at the inlet and outlet of the shot blasting machine requires the capacitors to be shot blasted to be sent to the door of the shot blasting machine through the V-shaped track; (3) First shot blasting: Set the shot blasting time to 15 minutes, the rotational speed of the shot blasting variable frequency motor is 2850rpm, the frequency is 50Hz, and the shot velocity of the steel shot is 64m / s; The shot blasting machine automatically opens the inlet and outlet doors, the left hanging bracket of the capacitor automatically enters the shot blasting chamber and closes the inlet and outlet doors, and the right hanging bracket is installed with the capacitor for preparation; The shot blasting machine works according to the shot blasting time and the speed of the shot blasting motor, and the capacitor hanging bracket rotates 360 degrees in the shot blasting chamber; After the shot blasting machine completes the work, it automatically opens the inlet and outlet doors, and the left hanging bracket with the capacitor exits to the original position through the V-shaped hanging bracket track, and use compressed air or a brush to remove the dust on the surface of the capacitor and the shot particles embedded in the weld; (3) Second shot blasting: The right hanging bracket (already installed with the capacitor) automatically enters the shot blasting machine; Set the shot blasting time to 15 minutes, the rotational speed of the shot blasting variable frequency motor is 2850rpm, the frequency is 50Hz, and the shot velocity of the steel shot is 64m / s; The shot blasting machine works according to the shot blasting time and the speed of the shot blasting motor, and the capacitor hanging bracket rotates 360 degrees in the shot blasting chamber; After the shot blasting machine completes the work, it automatically opens the inlet and outlet doors; After the capacitor shot blasting is completed, it is installed on the trolley and sent to the next process; (4) Inspection: The surface color of the capacitor case is silver-gray; The shot blasting roughness on the surface of the case is uniform, and there is no phenomenon of missed shot blasting; No scratches, spots, or fingerprints should be observed on the surface of the case after shot blasting; The color of the case weld and the installation bracket is not significantly different from that of the case; There is no dust and residual shot particles on the surface of the capacitor; (5) Appearance treatment: Hang the capacitor on the special production line, and coat the entire surface of the capacitor with a high-strength stainless steel protective film liquid, and it cannot be taken off the line until it is naturally dried for at least 4 hours; (6) Dismounting: Install the capacitor on the trolley and enter the packaging and warehousing process.

[0015] Among them, the deviation of each of the above times can be within ±5%.

[0016] Furthermore, by repeating the steps (2) to (5) of the above process, the appearance treatment of multiple capacitors can be carried out.

[0017] Furthermore, when the operator removes the capacitors from the production line, gloves must be worn, and when using a fixture to carry the case, it must not touch oil stains or water droplets.

[0018] Furthermore, when carrying capacitors, it is strictly prohibited to touch the case with hands to avoid damaging or scratching the surface of the case.

[0019] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A process for processing the appearance of a film capacitor for rail transit, the process comprising the following steps: (1) Preparation: Cover each film capacitor insulator with a cover; add stainless steel shot blasting particles into the shot blasting machine; (2) Shot blasting preparation: Use the lifting equipment to hang the film capacitor on the hanger, and shot blast two film capacitors at a time; start the dust collection device and the shot blasting machine power supply. The inlet and outlet of the shot blasting machine are V-shaped hanger tracks. The film capacitors to be shot blasted are sent to the door of the shot blasting machine through the V-shaped track; (3) First shot blasting: Set the shot blasting time to 15 minutes, the speed of the shot blasting variable frequency motor to 2850rpm, the frequency to 50Hz, and the steel shot blasting speed to 64m / s; the shot blasting machine automatically opens the inlet and outlet doors, the left hanger of the film capacitor automatically enters the shot blasting room and closes the inlet and outlet doors, and the right hanger is loaded with the film capacitor for preparation; the shot blasting machine works according to the shot blasting time and the speed of the shot blasting motor, and the film capacitor hanger rotates 360 degrees in the shot blasting room; after the shot blasting machine completes the work, it automatically opens the inlet and outlet doors, and the left hanger with the film capacitor withdraws to its original position through the V-shaped hanger track, and the dust on the surface of the film capacitor and the shot blasting particles embedded in the weld are removed with compressed air or a brush; (3) Second shot blasting: The right hanger automatically enters the shot blasting machine; the shot blasting time is set to 15 minutes, the speed of the shot blasting variable frequency motor is 2850rpm, the frequency is 50Hz, and the steel shot blasting speed is 64m / s; the shot blasting machine works according to the shot blasting time and the shot blasting motor speed, and the film capacitor hanger rotates 360 degrees in the shot blasting room; the shot blasting machine automatically opens the inlet and outlet doors after completing the work; the film capacitor is shot blasted and loaded onto a trolley for the next process; (4) Inspection: The surface color of the film capacitor case is silver-gray; the shot blasting roughness of the case surface is uniform, without any missed shots; no scratches, spots, or fingerprints should be observed on the case surface after shot blasting; the case welds and the color of the mounting bracket should not be significantly different from the case; There is no dust accumulation and residual shot blasting particles on the surface of the film capacitor; (5) Appearance treatment: Hang the film capacitor on a dedicated production line, apply high-strength stainless steel protective film liquid to the entire surface of the film capacitor, and dry it naturally for 4 hours; (6) Unloading: Load the film capacitors onto a cart and enter the packaging and warehousing process; Among them, the deviation of the above times can be within ±5%.