Die – casting aluminum process technology

With economic development rapidly , and china manufacturing industry also is  developed in modern society rapidly. Improving industrial level and innovation, it is the trend in die casting industry.

Die casting is a kind of precision casting method which let the metal change to complex metal mold shape by the high pressure. In 1964, the Japanese Association defined die casting as “in the high temperature will be pressed into the molten alloy precision casting , casting in a short time a large number of production of high precision and excellent casting surface”.

The USA called it Die Casting, the UK called it Pressure Die Casting, but in china are familiar with the Japanese saying, known as Die Casting, so the castings are manufactured by the die casting method called die castings, and you know the tensile strength of these materials is almost twice as high as that of ordinary cast alloy. next let’s discuss the application and die casting characteristics of aluminum alloy die-casting products in die casting industry.

die-casting-aluminum-process-technology

The aluminum alloy die-casting products are mainly used in electron, household appliance and communications industry etc. Now it is also applied in many LED lights, as heat sink of the LED flood lights is used integral die-casting aluminum radiator technology.Its advantages is weight lighter, transportation costs lower,an excellent luminous efficiency and a long service life, rather than other heat sink slowly.

However, now the aluminum alloy die casting products are more widely used because of its own unique characteristics, it is used in large aircraft, ship and other relatively high requirements of the industry.

LED aluminum shell die-casting is zinc ingot mold generally, the transmission rate of about 80~90W/M.K (w / M. C), small power many basic 1-3W using this process. The advantages is low cost, fast production,but the heat dissipation is worse.

Aluminum Purity: 98% the following properties of aluminum, hard and brittle, only foundry casting products. Therefore, most of the aluminum alloy die castings, including LED lamps die casting shell is the use of aluminum, because the production of aluminum is only suitable for the production of die castings, and high hardness, low cost. In addition, the die casting LED lamp shell has an advantage in mass production, because the production of die casting speed is very fast, the production cost is low.

The aluminum alloy die casting is high performance on strength and hardness commonly, because its surface is special treatment, such as electroplating, electrophoretic paint, spray, sand blasting, anodizing, paint, high temperature paint, rust and passivation etc. Different surface treatment process, the product of the requirements are not the same as the tolerance.

In general speaking, the aluminum alloy die casting main resistance testing includes neutral salt spray, RCA tape abrasion test, abrasion test, pencil hardness test, 100 lattice test etc.

aluminum-alloy-die-casting-main-resistance-testing

Now more and more design use luminum alloy die casting,due to the good heat dissipation, low transportation costs, metal utilization, the structure advantages.

Advertisements

Electronic Ballast Introduction

The electronic ballast is used electronic technology to drive electric light source, which is one requirement of lighting electrical equipment. Now more and more LED lights also used electronic ballast because it’s lighter and even is integrated with the light .And more, it is as starter, which can remove the individual starter. And improving the current frequency or current waveform to adjust the phenomenon of the flicker of fluorescent lights. Let fluorescent light can use DC power supply.

traditional-electronic-ballast

 

The electronic ballast is a conversion device that converts the power frequency AC power source into the high frequency DC power source, its basic principle is the power supply directly become DC power supply through the radio frequency interface filter, full wave rectifier and passive(or active) power factor corrector(PPFC or APEC).

electronic-ballast-circuit

Through DC/AC converter, high frequency AC power output of 20K-100KHZ, and the lamp is connected to a series resonant circuit and resonant heating filament, high voltage on the capacitor, and at both ends of the lamp, but the lamp “discharge” into the “on” state, then enter the luminous state at high frequency inductive limits current increase effect of guarantee lamp to obtain a lamp voltage and lamp current required for normal work, often set up all kinds of protection circuit, such as abnormal protection, surge voltage and current protection, temperature protection and so on.

led-electronic-ballast

The electronic ballast has 4 series of 16 varieties, include one common type and special electronic ballast, lamp box type is divided into 20W, 30W, 40W a total of 6 species, one for two, ordinary and special electronic ballast box type is divided into 2x20W、2x30W, 2x40W a total of 6 species, ring lamp electronic ballast is divided into 22W, 32W, 40W, a total of 3 species, last one is the quartz bactericidal lamp ballast for 35-60W a total of 1 species.

All different dimension lights are used in different field, such as the one for one and one for two light electronic ballast are designed specifically for outdoor light boxes and outdoor billboard, because it has the advantages of waterproof, high insulation performance, and the light box cloth doesn’t turn yellow because of the heat.

Electronic ballast is suitable for different occasion for general lighting. Ring lamp electronic ballast is suitable for the installation of the balcony in the home lighting, staircase corridor lighting and other public places. The quartz bactericidal lamp ballast can be used for shops, display windows, exhibition halls, jewelry stores, bars, museums, shops, etc.

Of course, the electronic ballast is more widely used in different because of its products have many advantages. Firstly what most attracts attention is the energy-saving, the lamp with the electronic ballast has low power consumption, the total input power of the lamp is decreased by about 20%, and the energy-saving effect is better.

It has no flicker and light more stable, it’s also beneficial to improve the visual resolution,improve the power efficiency, alleviate visual fatigue so that is beneficial to eye protection. Its power factor reach about 0.95, it means that not only reduces the cost of investment, but also reduces the loss of energy.

Furthermore, it has the stability of input power and output luminous flux, although power supply, voltage deviation maybe is very large, it can still maintain a constant power source, stable light intensity, energy-saving as well, the last is that can prolong the lifespan of the product. However, it has some disadvantages such as the problem of heat dissipation, because heat dissipation is an important factor affecting the lifespan of electronic ballast, and this aspect still needs to improve, but in a word , the electronic ballast has a big development space.

 

How important secondary optics design is in led applications

Due to the variety and complexity of lighting requirements, based on the principle of light distribution, we use the optical transmission design with traditional design method. Then  secondary optical design is published according to its feature of unique light distribution, it meet the national lighting standard , and reduce the design complexity, which is used LED flood light or LED street light design .

The basic function of secondary optical design is to make light source spread out, next to gather the light in a smaller range. Now it is used material with silica gel lens, optical lenses PMMA lens, PC lens and the glass lens commonly, etc.

led-lens

Considering the transmittance, production efficiency, manufacturing difficulty, heat resistance and processing cost, PMMA lens is widely used in many fixture and become mainstream increasingly, its light transmittance can reach 93% . You know most of LED flood light adopts the PMMA lens, its advantages is high thermal conductivity, small light failure, light color purity, no ghosting, and high brightness.

Then let us deeply know the optical lens design. It’s said that the designing idea of the traditional lamp is band coefficient method, which is under the condition of known light distribution and target light distribution, divided the target lamp into a series of light band according to appropriate view, so each band has a corresponding band coefficient, corresponding to the light source is also divided into a series of band, also to calculate the flux in the band, so it’s too difficult for us.

Lens simulation software to establish the secondary optical lens entities, and entities need to be given material properties and surface properties, according to the previous analysis, PMMA lens is the main product material. Surface feature corresponding to the light transmittance of the material, the penetration rate of 3mm thickness generally can reach about 93%, and the material of different wavelengths of light refraction properties is relatively uniform,when tracing, using a single wavelength to improve the efficiency of

The LED light is used in different field. For instance, the LED flood light is installed on the wall for passers in the night.Due to the influences of light source, a normal light maybe easy to form a glare and round without the light distribution. In order to solve this problem, need to improve the light distribution of LED, it means that should design a secondary light distribution. At the same time, you know people prefer to warm white,if it is required the light penetration in fog days, so the light need yellow spectrum to create a better lighting environment for people.

Actually, the purpose of secondary transmission design is to meet the application requirements by changing the light beam angle and light distribution . The secondary optical lens design can solve the problems of LED flood light and LED street light,just like the light efficiency/the light uniform/the angle of light distribution/glare and safety effectively etc. Of course, the secondary optical transmittance lens still has a reference significance to realize green lighting.

 

7 ways to ensure led fixture light quality

7 ways to ensure led fixture light quality

The high-power LED demand is more and more prosperous , also the LED quality requirement need higher than before, mainly reflect in the following 7 aspects:

high-quality-led

1.International testing standards- AQL

The LED light’s detect standard is classified with four grades:

1.1 Slight: LED bulb function is normal, but it still have a little flaws in the appearance and other aspects, AQL=2.5;

1.2 Genera: LED can work properly, but it’s also affected by its defect function.AQL=0.4;

1.3 Serious: LED can’t work properly, it seriously lacks the relevant functions.AQL=0.15;

1.4 More serious : LED isn’t work at all, and maybe happens security risks, so it isn’t followed to appear in the market.AQL=0.

led-quality-control-aql

Other is our experience summary.

2.Forward voltage test

The forward-voltage range is within the permissible range of the  circuit design, then the forward-voltage size will directly influence the overall circuit parameters, so it is a hidden trouble for product quality. In addition,for the circuit power requirements, want to ensure same luminous efficiency, the forward voltage is more lower is more better.

3.Luminous flux

LED user is care about Luminous flux measure, and knowing their LED Luminous flux range, so ensuring their product brightness uniformity and consistency.

4.Reverse leakage current test

Reverse leakage current is injected a certain voltage which should be lower than the required volume.During operating, Static electricity, led chip quality and other factors can lead to high LED reverse leakage current. It also a hidden trouble for LED product quality, may having LED dead lights phenomenon.

5.Main wavelength

For monochromatic light LED, the dominant wavelength is an important indicators to measure its color parameters, and it directly reflects the human eye visual perception on the LED light.

6.Color rending index

The CRI is related to the object discoloration extent from the light directly , it’s very important for the LED products.

7.Relative color temperature

For the white LED, color temperature is a parameter that often be measured by its color industry, and it can directly show up whether the LED color tone is warm,cold or right white.

 

 

7 ways to choose China reliable supplier in international trade?

7 ways to choose China reliable supplier in international trade?

1.Real Register Company

It shows company/factory status truly, all files information consistency,including business license and registration certificate.

The sales staff generally say that their company’s quality is good, they have rich industry experience, then has honesty and trustworthiness, however I would say that most of it is credible, but if you are unlucky, you still meet the fake company.

So you must see the corporation license in relevant government departments, which can help you to have rights and kinds once you have a dispute with the company. As you know, the office address and the sales staff can be changed, but the corporation license is a legal effect.

Then,the people who business many

years with Chinese also know that your china supplier both have Hong Kong and China mainland receivables account for international business. Hong Kong company’s use registration certificate, and it must update every year with government. The China mainland company is also. If you want to know when the company be set up, you should see its earliest registration certificate.

2.Quality problem

It’s a prerequisite that what king of product quality you want to have, is determined by buyer rather than the Chinese supplier. For instance, it’s impossible to make value equal to UD$100 by UD$50 .But we can request the top quality by US$50 with UD$50 value . Buyer can use data to control quality.

Let them provide AQL report , then we can demand that would be rework if beyond a percent , Or to get a discount certain ,or give more free spare part.

Generally the Chinese suppliers cannot will not easily agree, because it is related to the profile. Then we have to go to the negotiation, we can try to a draft, it’s better to accept, the reliable supplier will cooperate you as much as possible.

If some supplier agree your demand easily,need pay more attention. He just want to get this order, don’t consider carefully.After he gets the deposit,he may tell your demand to high who can’t meet it. Then buyer is passived.So buyer can write all special quality demand in PI.So my point, if the suppliers will cooperate effectively and achieve the buyers’ goal who will be put in Reliable suppliers lists.

3.Delivery time

There is a delivery time in each quotation. The fast is from 5 to 20 working days, the low speed is from 35-60working days. But a reliable suppliers is not must the fastest delivery time. As a buyer need to know the Deadline  local Warehousing , then estimate the order delivery time, let the Chinese suppliers before this date. But the reality is that In China, 70% of small enterprises are delayed delivery, because their suppliers will delay to them,who give VIP customers supply firstly,. So I concluded that the Chinese suppliers keep their promise date for you, buyer can put in the reliable suppliers lists.

4.Price

Price is a necessary factor, but it isn’t the only one.In same industry, actually, price is more or less.if  price is much more different, maybe their brand effectiveness is more different,or can give some different value. To sum up, it is reasonable(middle) price in one industry ,can put in the reliable suppliers lists.

5.Payment types

Many buyer want to use the letter of credit,which is considered if buyer is famous brand or re-order.. Buyer want to use L/C for first order, you have to prepare to have a long-negotiation.And the normal payment items is Exwords factory,other is need negotiation.FOB Hong Kong can be accepted. Then 30% Deposit,70% Deposit is normal.So I concluded that if they will use L/C payment in

Future business,and all your payment they will try to test. types at their second trade, it can put in the reliable suppliers lists.

6.Service

After-sales service, warranty service, technical support service,etc. I want to say that it can reflect a reliable suppliers service is not normal status is to face the problems and difficulties.So if the buyer in trouble status,and a china supplier try their best to help you,and no get any profits.I can say not just a reliable suppliers, but the quality of long-term cooperation partner.

7.Website

Buyer can know many information by visiting supplier website,not only long-term product layout, but also the developmental ability of new product.

Actually, buyer don’t believe to many engineers and equipment in supplier company from sales mail,you can open a official website of Chinese suppliers ,then you can realize.From supplier website, You can know Chinese suppliers culture?what’s the latest news? Is there an industry trend analysis? Have any professional knowledge? And so on. if the website not only bring good user experience, but the products are particularly competitive, and we can also learn more industry professional knowledge, so this Chinese suppliers can be put in the reliable suppliers lists.

At last, .to do long-term business, there must be several reliable suppliers to support you.it’s very hard to find a reliable and long-term cooperative suppliers, it need time to develop and foster.Only a win-win situation,it can build a long-term cooperation relation

This is my original intention of writing a blog, I hope to share my experience of foreign trade, if can be useful to you, I have great sense of accomplishment.