Steel structures can be used in many
industries such as foundation reinforce, electric power transmission structures
and tubular scaffolding, etc.
A flange can also be a plate or ring to form
a rim at the end of a pipe when fastened to the pipe. A blind flange is a plate
for covering or closing the end of a pipe. A flange joint is a connection of
pipes, where the connecting pieces have flanges by which the parts are bolted
together.
Although the word flange generally refers to
the actual raised rim or lip of a fitting, many flanged plumbing fittings are
themselves known as 'flanges':
There are many
different flange standards to be found worldwide. To allow easy functionality
and interchangeability, these are designed to have standardised dimensions.
Common world standards include ASA/ASME (USA), PN/DIN (European), BS10
(British/Australian), and JIS/KS (Japanese/Korean). In the USA, ANSI stopped
publishing B16.5 in 1996, and the standard is ASME B16.5
Steel Structures,Steel Structure Building,Classic Steel Structure,Light Steel Structures Yixing Steel Pole International Trading Co., Ltd , https://www.yx-steelpole.com
According to the LED production process, the industry can be divided into three industrial chains: upstream epitaxial wafer growth, midstream chip fabrication and downstream chip packaging.
The upstream epitaxial wafer grows into a key technology for LEDs with the added value. The single wafer is the substrate, and sapphire is currently used more. Epitaxial wafers of different material layers can be grown on the substrate by using different materials. The existing size is 2 inch and 3 inch epitaxial wafers, and the thickness is very thin like flat metal, and then used for midstream.
According to the needs of the LED component structure, the midstream manufacturer first performs metal evaporation, and then etches and heat-treats the epitaxial wafer to form metal electrodes at both ends of the LED, and then the substrate is thinned, polished, and cut into small LED chips. Due to the brittleness of the substrate and poor machinability, the yield of the chip cutting process is the focus of the midstream production stage. The final step in the middle reaches is to test the sorting.
Downstream, the chip from the middle is pasted and welded to the lead frame, which is tested, sealed, and packaged into various products. In principle, the smaller the chip, the higher the technical difficulty of the package. However, compared to the upstream, the technical content is still relatively low. Therefore, in addition to the diversification of packaging capabilities, there are also ways to increase the high-power LED products with high packaging difficulty to enhance profit and competitiveness.
Because the quality of the mid-stream chip production is mainly determined by the upstream epitaxial film, the correlation between the two is very close. In general, upstream manufacturers will also carry out the chip production process, and midstream manufacturers will also extend upstream in order to control quality. Therefore, the upstream epitaxial wafer growth and the midstream chip manufacturing are often integrated, and the two together account for more than 70% of the total LED industry output value.
LED production process
In addition to these three, the broader LED industry chain includes the manufacture of substrates (substrates) and the development of LED applications after chip packaging. The former can also be attributed to the materials industry, which can be classified into various application fields.
The epitaxial wafer growth of LEDs mainly includes LPE (liquid phase epitaxy), VPE (vapor phase epitaxy) and MOCVD (organic metal vapor phase epitaxy) technologies. The former two are mainly used to produce conventional LEDs, and the latter are used to produce high-brightness LEDs. As high-brightness LEDs become more and more mainstream in LEDs, the newly purchased epitaxial wafer growth devices are all MOCVD.
LED main epitaxial wafer growth technology
Different substrate materials, and different luminescent layer materials, correspond to different wavelengths, and also correspond to different colors. Since blue-green and white light are the future development directions and are now mainstream products, sapphire is currently used most as a substrate.
LED epitaxial wafer material classification
The LED product packaging structure is generally divided into three types: point light source, surface light source and light-emitting display. A single die generally constitutes a point light source, and multiple die assemblies generally constitute a surface light source and a line light source for information, status indication and display, and illumination. The display is also a combination of multiple dies in series and in parallel.
LED main packaging technology
At present, the major LED manufacturers in the world are Nichia, Toyota Synthetic, CREE, GELCORE, LUMILEDS and OSRAM. These international companies are mainly distributed in Europe, America and Japan. They have the main patents of LED technology and are also the main development force of LED frontier technology.
Nichia (Nic Hia)
There are nearly 200 MOCVD equipments, mainly monolithic. The substrate used was mainly sapphire. Production of blue, green, violet, ultraviolet, white light low power (<20mW), medium power (20-50mW), and high power (>50mW) LED products. Only LEDs and follow-up products are sold, and the die and epitaxial wafers are not sold. Phosphor technology is very mature.
The products are widely used, and almost all of them related to GaN-LED have their products. Especially in the outdoor full-color large screen, it is almost monopolized by the Japanese company.
It has a global market share of about 20 to 30%.
Toyota Synthetic (Toyota Gosei)
The self-made MOCVD equipment has a larger output than Nichia, and the product quality is slightly worse than that of Nichia. Sapphire substrate. Only LEDs and follow-up products are sold, and the die and epitaxial wafers are not sold. Production of blue, green, violet, ultraviolet, white light low power (<20mW), medium power (20-50mW), and high power (>50mW) LED products.
The products are widely used, and almost all of them related to GaN-LED have their products. However, the outdoor full-color large screen cannot be compared with Nichia.
It has a global market share of about 20%.
CREE
There are both MOCVD equipment purchased on the market and MOCVD equipment developed and improved by ourselves. Mainly multi-chip MOCVD equipment produces GaN-LEDs. The substrate used is SiC, which has a very mature SiC single crystal production technique and is easy to obtain SiC substrate materials. Only LED epitaxial wafers and dies are sold. It can produce blue, green, purple, ultraviolet light low power, medium power, and high power LED epitaxial wafers.
The products are widely used, and almost all of them related to GaN-LED have their products.
It has a global market share of about 10%.
GELCORE
GaN-LED epitaxial wafers are mainly produced by EMC OR MOCVD equipment. The substrate used was mainly sapphire. GelCore can produce blue, green, violet, ultraviolet, white light low power, medium power, and high power LED products, but high power products are still relatively immature. Pay attention to white LEDs. There are strong advantages in lighting design.
The products are widely used, and almost all of them related to GaN-LED have their products. Especially the high-end lighting market (such as architectural decoration lighting).
LUMILEDS
It is mainly sapphire and also uses a GaN substrate. Only LEDs and subsequent products are sold, and the die and epitaxial wafers are not sold. Production of blue, green, violet, ultraviolet, white light low power, medium power, and high power LED products. In particular, it can produce high-power LED products with a power of 5W. Focus on high-power white light lighting.
At present, the output of LUMILEDS products is not very large, but its high power production. 