The quality of the chrome layer is directly related to the stability of the current density. The quality of the chrome layer directly affects the surface quality of the components. In order to ensure the quality of the parts coating, the cycle is generally used to improve the current efficiency and electroplating speed, which makes the plating layer crystal finely, good uniformity, strong ductility, abrasion resistance, resistance Strong corrosion performance. These processes are performed in different current density, and DC pulse control is required to control it in a certain range.
With the development of electronic technology, electroplating workers have felt that most of the performance of the pipe tube rectifier is better than ordinary DC power supply. However, the process of the phase control process of the crystal tube, with the changes in the angle of the pilot, the average value caused by the average value and the peak value are large, so that the smoothness of the current density is poor. According to the conclusions obtained from the relevant data, the ripple factor of the power supply is greater than 5%of the chrome grain sorting and displacement.
Under the guidance of this new idea, in October 2001, I designed a 15000A/12V positive and negative output low -ripple power supply with a crystal tube, which are the chrome chromium plating test for various types of large products of various types. Essence
1. \u0026 nbsp; Modern technology is a guarantee of high -quality chrome layer
Electro -plated workers use single -phase full waves, three -phase and half -phase silicon rectification power supply chrome, chrome -plated layer surface surface Black, gray, and white appear separately. The original factory used an ordinary hexagonal rectifier for chrome chrome, and its life test was only half of the product life indicator. These valuable data are the basis for creating new products for power workers. The current trend of power supply components is to use the self -off -cutting crystal triode and its closure of the crystal tube, and the control method adopts discrete type (digital) and continuous (simulation). The former adopts the principle of PWM adjustment. Due to the power limit, the secondary breakdown and the complex manufacturing process, the cost is relatively high. The power supply drops to 3 ~ 4V on the smooth electrical resistor, and the loss is relatively large.
Placing at the level is relatively high in performance of the power supply, especially the ripple factor and stability accuracy within the chrome -plated process control curve range. Only by maintaining a certain current density accuracy can the quality of the chrome layer be guaranteed. According to the relevant information and experience, the solution in the gauge has a chemical reaction when the current density is greater than a certain value. When the current or 20%of the current or voltage of the ripple factor is set at the rated power spare parts, the ripple factor is less than 5%, and the control accuracy is required to be 1%.
In order to ensure the performance of the power performance meets the above process, I designed the KF low ripple power supply (see the picture), which is characterized by:
(1) \u0026 nbsp; Wave factor, reducing energy loss and improving the harmonic interference of the grid;
(2) \u0026 nbsp; adjustment method, adopt a continuous PI regulator than a closed -loop and dual -channel PI, the tracking speed and high accuracy;
(3) \u0026 nbsp ;control method,According to user requirements, soft start, manual, and cycle direction, process curve control and computer monitoring interface;
(4) \u0026 nbsp; protection functions, adopt pressure limit, current limit, overvoltage, overcurrent, lack of pressure, lack of lack Phase, and short -circuit protection functions;
(5) \u0026 nbsp; adopt a multi -phase converter, the main circuit of the power supply below 10000A uses a balanced electrocomputer, and the main circuit of the power supply above 10000A does not use a balanced electrical resistor, using a variety generator, using a variety generator, using a variety generator. Make the equipment structure simple and good heat dissipation.
2, \u0026 nbsp; kf main data and usage status:
In practical applications, due to the electroplating grooves as a resistance load, the measured SV can also be reduced by 1%to 2%. \u0026 nbsp;
3． \u0026 nbsp; KF rectifier’s performance compares with chrome quality:
(1) The quality of chrome-plated is affected by the stability of current density
Our company uses KF-15000A power supply to use program control in the use of program control Process processes, such as cleaning workpiece → Electric punching process to quickly combine the workpiece and electroplating layer → milk white plating to uniformly refine the crystal → slow -up chrome layer transition smoothly to reduce the stress of the two types of chromium. The comprehensive performance of high static control accuracy and low ripples to ensure the stability of the current density. The two -year process comparative life test of the rectifier and other rectifiers. The rectifier is good.
(2) The electroplating quality is related to the current
Due to the small current output of the auto -coupled regulator, the two plating interfaces are obvious when the large -plated workpiece. The output current of the KF rectifier is large, continuous and smooth pressure regulation to achieve a uniform surface quality of the plating device, and the electroplating speed can be increased by 1.8 times.
(3) Large range of chrome -plated quality and smooth current density of workpieces
Profile Extrusion line Pass
Due to the different number of flowers in the crystal tube, the average output average is different from the peak value. Essence The more the number of phases, the lower the peak value. Under a smaller flat wave electrical resistance, the output current has a small pulse. In addition, when the frequency is high at low voltage, the current is easy to continuously. Therefore, the KF rectifier can successfully complete all the company’s collaborative extra -large plating in each company.
(4) The quality of chrome -plated is related to the reliability of the system
The power supply is unreliable, and the plating parts in the plating fluid are comprehensive in the crystal world of metal, selective corrosion, stress corrosion and other comprehensive comprehensives Sexual processes have exacerbated the micro roughness of the surface of the workpiece. At the same time, the hydrogen analysis during self -corrosion generates the suction hydrogen on the surface exceeding the balance, which exacerbates the plating hydrogen and brimming. In terms of accuracy, the current measurement current changes at 10000 ~ 10010A, and the voltage 11V remains unchanged. KF rectifier current is 11000 ~ 12000AInternal changes, the voltage changes at 10.00 ~ 10.10V.
4. \u0026 nbsp; Endmark
KF series rectifier, which is based on the problem of current density stability and the problem of chrome -plated quality and surface treatment.EssenceUnder the conditions of modern technology, the KF series rectifier indicators are better.