Shows all kinds of rectifier knowledge in rectifier industry, of course, the mostly usage is in plating machine area.

Pulse power supply gold plating

Pulse power supply gold plating

Pulse power supply gold plating superiority:

The superiority of pulse power supply plating can be better reflected especially on gold plating. Pulse power supply gold plating could obtain dense crystal electroplating layer coating, that not only significantly increased its finish degree, corrosion resistance, weldability, wear resistance, high temperature capability and have a greater degree of discoloration, but also greatly saved gold.

Pulse power supply gold plating

Pulse power supply gold plating

Someone think no need pulse power supply gold plating:

But there is a view: that barrel gold electro plating using pulse power supply of little significance to improve the density, which their reason is that the barrel plating machine tumbling action make the coarse crystals can not grow, therefore can get dense electroplating layer coating, bright, so no need use a pulse power supply. This view seems not unreasonable, but that is biased. Because barrel plating machine tumbling just a mechanical polishing action, its limited capacity and can not replace the role of fine-grained action generated large pulse current by electro chemical polarization. Therefore, if there is high quality requirements of gold plating, still need to use pulse rectifier gold plating, which this is the best control method outside the plating tank.

Vivid explain to tell you why need pulse power supply gold plating:

For example, now integrated lead frame, linear tube shell, connectors and other parts the pulse power supply barrel plating has been very common.
Also, there is gradually formed a consensus that gold plating bottom plating – nickel layer electroplating should also adopts pulse rectifier plating. The reason is pulse-plated nickel layer of stress, density, uniformity is far superior to the DC rectifier nickel plating, which undoubtedly will lay a solid foundation for gold electro plating, thus greatly improving the functional indicators of gold plating.
For example, one electronic products factory choosing pulse rectifier plating for products gold plating, and the thickness of the gold electro plating layer meet the requirements, which plating workpieces appearance is also good, but still can not meet the 380 ℃ ~ 450 ℃ temperature assessment test. Then they hire experts to help them to solve the problem. One of the measures is to use a pulse power supply nickel barrel plating instead of DC power supply, of course, there are other measures, such as strict operation, improved Pulse power supply gold plating liquid formulations and so on.

The parameters pulse power supply gold plating adopt can refer to the following:

Single pulse: 10% to 20% duty cycle (turn on: 0.1ms ~ 0.2ms, turn off: 0.8ms ~ 0.9ms), pulse frequency 900Hz ~ 1000Hz, the average current density equal to or slightly larger than the DC power source plating;
Reverse pulse: positive pulse duty cycle of 20% (turn on: 0.2ms, turn off: 0.8ms), working time 100ms, the average current density equal to or slightly larger than the DC rectifier plating;
Reverse pulse duty cycle of 10% (on 0.1 ms, off 0.9ms), working time 10ms, an average current density of the reverse peak current density of the positive peak current density of 1 to 2 times, obtained by calculating backwards.

But many people believe that when acidic gold plating, because the gold anode insolubility, reverse peeling double pulse does not work, so the use of the double pulse is superfluous. In fact, the double pulse reverse reeling gold plating only improve the uniformity small, but it can not say that is superfluous, or can not say there is no significance. There is a small experiment may indicate the presence or absence of other dual pulse gilded significance. In the same acidic gold plating solution, the same current density, respectively, DC power source, single pulse, double pulse at the same time each plating a test piece. Comparison of three test pieces, can see clearly that the plating coating brightness is incrementally from DC to single pulse and then to double pulse power supply gold plating.

This shows dual pulse reverse stripping gold plating for improving the crystallization is advantageous, otherwise adopting double pulse plating will not more bright than the single pulse. This should be due to that though reverse pulse not achieve anodic dissolution, but can play the role of electro-polishing, which facilitates the subsequent cathodic deposition coating pulse period is more detailed, bright.

Further, reverse pulse may also have the plating coating be more fully in the subsequent recrystallization cathode pulse period effect, and thus the plating layer coating will be finer grain.

But the reverse pulse work time shall not too long (less than 1/10 of the positive pulse time), otherwise the deposition rate is slow. Also, reverse pulse peak current density should not be less than the positive pulse, otherwise reverse electro-polishing effect is not obvious. Double pulse barre plating as well. Decorative gold plating barrel plating time is short, thin plating coating, good brightness Ni underlying coating nonfunctional requirements, so generally not suggest the use of pulse power supply plating, in order to save the cost of expensive pulse rectifier. But production practice shows that, use double pulse power supply gold plating, if select parameter properly, plating time can be shortened more than 1/3, so as to achieve the effect of the save gold.

Hard oxidation rectifier

Hard oxidation

Hard oxidation and ordinary oxidation difference: Hard anodized oxide film has 50% penetration inside the aluminum products, an another 50% attached to the aluminum workpieces surface, so after a hard anodizing exterior of the product size becomes bigger, the hole becomes smaller, while after hard oxidation the external dimensions of ordinary oxidation becomes smaller and the hole becomes bigger.

Hard oxidation colors:

Hard oxidation colors usually made of black and oxidation film true colour (natural color), true color is determined by the aluminum alloy composition, even the same type of aluminum ( for example 6061-T6), and different manufacturers, the color of the oxide film is different, if Aluminum use same manufacturer the same type of material maybe colors are different, and therefore, the true nature of the oxide film is generally used for the internal parts of the product.

Hard oxidation aluminum advantages:

1, Aluminum hard anodizing surface hardness can even up to HV500, which can compare to chrome plating;
2, The hard anodizing film thickness from 25 to 250um;
3, Have features of strong adhesion, according to the generated hard anodized oxidation characteristics: hard oxidation film has a 50% penetration in aluminum inside,
50% adhered to the surface of an aluminum alloy;
4, Good insulation: breakdown voltage up to 2000V;
5, Great wear resistance: for if copper content more than 2% in aluminum alloy, its maximum wear index of 3.5mg/1000rpm. All other alloys wear index should not exceed than 1.5mg/1000rpm;
6, Non-toxic: the oxidation film and for anodic oxide film produced by an electrochemical process there is no toxic to humans.

So now a lot of industry in order to facilitate machining and reduce the weight of products, and environmental protection requirements, some hard oxidation aluminum alloy parts products are currently to replace stainless steel, and conventional spray, plating treatment process.

Hard oxidation real case:

This customer use our Hard oxidation pulse power supply for aluminum pot hard oxidation, the result is very good. You can see the below surface, the hardness also very good, there is no any scratch on surface even use a knife to cut the aluminum pot hard anodizing surface.

2000A90V Hard oxidation rectifier, using our power supply you can get very good treatment even 2 & 7 series aluminum grade.

Oxidation pulse power supply

Oxidation pulse power supply

Hard oxidation pot using our pulse rectifier

Hard oxidation pot using our pulse rectifier

Hard oxidation pot using our pulse power supply

Hard oxidation pot using our pulse power supply

Electrolytic power supply

Our company specializes in design and manufacture and sale of silicon controlled rectifier, high-frequency switching pulse power, high-power switching power supply, oxidation power supply, electrolysis power supply, electrophoresis rectifier, coloring power supply, electroplating rectifiers, experimental power supply.

High frequency electrolytic power supply description:

1, Can configure a single main cabinet or double main cabinet plus control cabinet structure according to user requirements.
2, When DC output current≥10 KA, adopt full circuit electrically coupled in parallel with the reverse-phase rectifier circuits, drastically reducing the eddy current losses and improve the efficiency of electrolytic power supply.
3, Control mode can be divided into: open loop (manual) and closed loop (automatic) two kinds according to production process requirements, and mutual conversion, DC current output phase number according to harmonic currents standard can be divided into 6,12 24,36 and 48 phase pulse rectifier, eliminating power rectifier 3,5,7 current harmonic pollution on the grid.
4. This series electrolytic power supply with over-current, over voltage, short circuit, under branches, under phase, high water temperature, water pressure, oil temperature and high/low, higher oil pressure protection, fully integrated control loop.
5, Major control board using high anti-interference high-power digital circuit triggers system, has a strong anti-jamming capability. And having advantages of high accuracy control, good stability, reliable operation.
6, Cabinet adopts cutting magnetic link, reducing the eddy current loss, the cabinet with a whole spray plastics.
7, Control methods: integrated analog control and computer control two categories.

High frequency electrolytic power supply application:

Mainly for non-ferrous metal electrolysis: aluminum, magnesium, zinc, lead, copper, manganese and manganese dioxide; gold, silver and other metal smelting; NdFeB rare earth smelting; carbide, diamond smelting; salt water, potassium electrolysis made caustic soda, potash, sodium system; fire electric heating material, as well as other types of high-power DC power supply.

High frequency electrolytic power supply specifications:

Electrolytic power supply output Current: 0-50000A;
Electrolytic power supply output voltage: 0-500V.

Electrolysis power supply

20000A High frequency rectifier

High frequency rectifier 20000A

High frequency rectifier

High frequency rectifier

High frequency rectifier development tendency:

Application in various power systems and power electronics, switching power supply high frequency rectifier technology are all at the core position. For large electrolytic plating power supply, conventional circuit is very large and heavy, if use high frequency rectifier switching mode power supply technology, which will be a significant decline in volume and weight, but also can greatly improve the power utilization efficiency, save materials and reduce costs. Electric vehicles and variable frequency drive, they are more indispensable switching mode high frequency rectifier power supply technology, electricity frequency changed by switching power supply, so can achieve nearly ideal load matching and drive control. High frequency rectifier switching power supply technology, also is all kinds of high-power switching power supply (inverter welding machine, communication power, high-frequency heating power, laser power supply, power supply operation, etc.) core technology.

High frequency rectifier frequency:

Theoretical analysis and practical experience shows that transformers, inductors and capacitors volume weight is inversely proportional to power supply frequency square root. So when we increase the frequency from 50Hz to 20kHz, increase 400 times, then the volume weight of electrical equipment is substantially reduced to 5 ~ 10% of frequency design. Whether inverter rectifier welder, or communication usage power supply switch mode rectifier, all show this basic principle. Similarly, the traditional “rectification industry” electroplating, electrolysis, electrical processing, charging, float charging, power closing with various DC power can also be transformed in accordance with this principle, a “class switching converter power supply”, the main material may save 90% or more, also saving electricity power at least 30% or more. Due to gradually increase the power electronic device operating frequency limit, prompting many of the original tube using conventional solid- frequency equipment, bring significant economic benefit in energy, water, economic saving materials, but also can reflect the value of this technical content.

High frequency rectifier specification and parameter:

High frequency rectifier Input voltage AC 3 phase 380V/415V/440V 50-60Hz
Output voltage 6V/12V/15V/18V/24V/36V/48V optional or according to customers’ request
Output current 0-20000A (Random optional)
Voltage stability ≤1%
Current stability ≤1%
Ripple factor 1%-2%
Efficiency ≥90%
 Stabilization mode Current stabilization/Voltage stabilization (Switchable easily)
Adjustment range Voltage/Current from 0-100% continuously adjustable within rated range
Cooling system Air cooling/Water cooling/Oil cooling
Control method Manual/PLC
Display contents Voltage meter/Current meter/Working/Over temp/Error, etc..
Protection method Input over voltage/Under voltage/Over current/Output short/Over heating self protection etc..
Operating temperature -20-50℃
Ambient temperature -30-65℃
Ambient humidity ≤90%
Working loading Full capacity operation, more than 1,000 meters above sea level, reduced load operation

High frequency rectifier  Packing details:

TypeLength (mm)Width (mm)Height (mm)Weight (kg)
Copper plating line

Copper plating line

Copper plating line

Copper plating line products

Copper plating line process:

Electroless copper plating line is a process for printed circuit board manufacturing, often called sink-copper or PTH, which is a self-catalytic redox reactions. First treatment with activator agent, adsorbed on insulating substrate layer surface of active particles usually as metal palladium particles (palladium is a very expensive metal, the price is high and has been rising, to reduce cost now practical colloidal copper process is in the application), copper ions are first reduced on these active palladium metal particle, which these reduced metal copper nuclei itself has become a copper ion catalyst layer, so that copper reduction proceed on these new copper nuclei surfaces.

Electroless copper plating: traditional copper plating mostly as vertical lines, process are similar, the general process is:
Cleaning → Neutralization → Degreasing → Microetching → Pre-ditching → Activation → Chemical copper plating.

The main components are cathode and anode in copper plating line:

Cathode: giving rise to the starting & end a couple of stainless steel rod having a pair of electrical contact ring, copper brush is pressed against the copper ring in order to get good contact, connected to the negative pole of rectifiers. By retaining roller, the cathode cut off contact with plating solution.
Copper plating line anode: 2 titanium plate installed in plating bath, these two anode pieces connect with positive rectifies pole by electricity cable directly. Anode soaked in chemical plating solution.

Chemical copper plating line principle:

Electroless copper plating on the surface of the catalytic activity by the action of a reducing agent to precipitate the copper ions reduced:
Reduction (cathode) reactions: CuL2 + + 2e- → Cu + L
Oxide (anode) reaction: R → O + 2e-
Thus, with hypophosphite as a reducing agent for chemical copper plating main reaction is: 2H2PO2- + Cu2 + + 2OH- → Cu + 2H2PO3 + H2 ↑
In addition to the establishment of the thermodynamics, chemical reactions must also meet dynamics conditions. Like other chemical copper as the catalytic reaction thermal energy is required to cause a reaction, which is why only when the chemical bath plating deposition get speed plating under certain temperature. Theoretically copper plating speed to express by increasing the concentration of the reaction product of reactant concentrations and reduce the speed. In actual use, the electroless copper plating solution containing certain additives, its have too many factors to effect, the situation becomes too complicated. Thus, most of the electroless copper plating dynamics research is limited to the most basic component of the bath at the start.

And copper plating line rectifiers normally as following specification:

Rectifiers for Copper Plating Line

Rectifiers for Copper Plating Line