Beijing Longyuan Pioneer of China's 3D Printing Industry

In the beginning of winter in Beijing, there was a slight chill, but the sky was clear and blue, with no clouds in sight. on November 15, 2012, the atmosphere in the Metropolitan Hotel was very warm, and a plaque unveiling ceremony was being held.

This was the inaugural meeting of the "Beijing Digital Manufacturing Industry Technology Innovation Alliance", where experts, scholars and entrepreneurs from China's science and technology sector, aerospace industry, high-end manufacturing industry, universities and colleges witnessed China's first industry alliance to impact the 3D printing industry. This move has attracted great attention from government leaders and the scientific research community, and everyone was excited about the China-made 3D printing products on the booth, which did not have a lot of exhibits, especially the products of Beijing Longyuan Automated Molding Systems, China University of Aeronautics and Astronautics, and Tsinghua University were notable.

    Echoing this, the global 3D printing industry has been in full swing. 2009, the United States took the lead in the publication of the "3D printing development roadmap", 2011 established the "3D Printing Industry Association", 2012, the Obama administration's initiative and the direct guidance of the establishment of the "3D Printing Alliance", the United States is striving to achieve "re-industrialization, remanufacturing" through the breakthrough of intelligent robotics, artificial intelligence, 3D printing three digital manufacturing technology. In 2012, at the initiative of the Obama administration and under the direct guidance of the establishment of the "3D Printing Alliance", the United States is striving to break through the intelligent robotics, artificial intelligence, 3D printing three major digital manufacturing technology, to achieve "re-industrialization, remanufacturing", to regain the dominant position in the manufacturing industry.

    The European Union has also set up funds to support 3D printing technology, respectively, in the University of Nottingham, the University of Sheffield, the University of Exeter established a 3D printing center, which the University of Exeter and other European regional development funds to support the establishment of £ 2.6 million investment in incremental laminar manufacturing center, in order to promote the Southwest of the United Kingdom and the surrounding economic development.

    In South Africa, in 2011, the South African National Laser Center (SANLC) and Aerosud, a South African aerospace manufacturing company, announced research on the Aeroswift project, with strong support from the South African Department of Science and Technology (DST), which has invested 28 million rand (about $3.4 million) in the project.

    3D printing technology has become the keyword to lead the future development trend of global manufacturing.

    With 3D printing technology as an opportunity, China also for the first time with the world's powerful countries, standing side by side in the starting line of high-end manufacturing industry research and development applications.

In China, there are only a few organizations engaged in 3D printing technology research, and only a few enterprises applying and industrializing 3D printing technology, and Beijing Longyuan Automatic Forming System Co. Founded in 1994, Beijing Longyuan was the earliest company in China to enter the research and development of 3D printing, and successfully developed China's first laser rapid prototyping machine in 1994, and devoted itself to the development of SLS rapid prototyping machine, as well as the application of rapid prototyping processing services. Has launched the AFS-360, 500, laserCore5100, 5300, 7000 and other models of SLS equipment (maximum forming space of 1400 × 700 × 400mm), with more than 200 users of equipment and more than 500 processing services, spread in the aerospace, shipbuilding, automotive manufacturing, and foundry industry and other broad areas.

Until today, only the United States, Japan and Germany can produce and process products with laser rapid prototyping machines in the world, and Beijing Longyuan's research and development and application have been synchronized with the world's advanced. As the pioneer of China's 3D printing industry, Beijing Longyuan has been walking on this lonely but charming road for a long time.

Twenty Years of Sword Sharpening and Fruit Making

    As early as in the mid-1980s, China put forward the implementation of a high-tech research and development program, which has a significant impact on the future economic and social development of biotechnology, information technology, automation technology, new materials technology, laser technology and many other areas, to establish 15 thematic projects as the focus of breakthroughs in order to track the world's advanced level. Under this situation, Beijing Longyuan Automatic Molding System Co.

The company was founded in 1994 with a registered capital of US$2 million, specializing in the research, development and sales of rapid prototyping equipment, and successfully manufactured China's first SLS rapid prototyping equipment - AFS-360 in the same year of its founding.

SLS rapid prototyping is a kind of 3D printing technology, 3D printing technology belongs to a kind of non-traditional processing technology, also known as additive manufacturing, rapid prototyping, etc., is in the field of global advanced manufacturing in the past 30 years, a set of optical / mechanical / electrical, computer, numerical control and new materials in one of the advanced manufacturing technology. With the traditional cutting and other materials "removal method" is different, 3D printing technology through the powder, liquid sheet and other discrete materials layer by layer accumulation, "natural growth" into a three-dimensional entity. The technology will be three-dimensional entity into a number of two-dimensional plane, greatly reducing the complexity of manufacturing. Theoretically, as long as the design of the structural model on the computer, you can apply the technology in the absence of tools, molds and complex process conditions to quickly turn the design into a physical object. The technology is particularly suitable for aerospace, weaponry, biomedical, automotive manufacturing, mold and other fields in small batches, structural asymmetry, curved surfaces and internal structure of the parts (such as aero-engine hollow blades, human bone prosthesis, with the shape of the cooling waterway, etc.) of the rapid manufacturing, in line with the modern and future development trend.

Feng Tao, Chief Engineer of Beijing Longyuan, graduated from Tsinghua University and worked at the Institute of Polymer Materials of Tsinghua University, has rich theoretical and practical experience in polymer materials and laser optics, and is one of the earliest experts engaged in the research of laser rapid automatic molding technology in China. He has deep attainments in the application of 3D printing technology and materials. As early as 1995, he proposed the application of SLS to rapid precision manufacturing. Compared with other 3D printer technologies, the most outstanding advantage of SLS is the wide range of molding materials it uses. Theoretically, any powder material that can form interatomic bonding when heated can be used as the molding material for SLS. Currently, the materials that can be successfully molded by SLS include paraffin, polymer, metal, ceramic powders and their composite powder materials. SLS has a wide variety of molding materials, material savings, and a wide distribution of molded part properties, plus SLS does not require the design and manufacture of complex support systems, which makes it suitable for a wide range of applications. Under his leadership, Beijing Longyuan has successively successfully developed complex process production methods such as casting molten molds, wax mold pressing and casting shells, as well as the application methods of polystyrene powder and synthetic materials in 3D printing.

    As the earliest company in China to realize the industrialization and service of 3D printing technology, Beijing Longyuan has been exploring and leading the 3D printing industry in China for 19 years, leading and promoting the development of China's 3D printing industry.

In 1994, we successfully manufactured the first SLS rapid prototyping machine in China, specializing in the development and sales of rapid prototyping equipment;

In 1995, it passed the expert appraisal organized by Beijing Municipal Science and Technology Commission; it was awarded a patent for invention;

In 1997, sintered materials for precision casting and rapid casting processes were successfully researched and entered the field of rapid development of complex metal structural parts;

In 1998, we participated in the rapid prototyping demonstration service center project of the Ministry of Science and Technology, and our equipment was selected by two service centers;

In 2000, the SLS-based rapid casting process for metal parts with complex internal cavity structure was successfully developed, laying the foundation for the rapid production of engine-type complex structural parts, and the direct molding technology for metal materials entered a substantial development stage;

In 2002, the research on direct manufacturing of metal parts by high-power laser was started with the China Academy of Engineering Physics (CAEP);

In 2004, cooperated with South China University of Technology to carry out selective laser melting metal forming technology. At present, the density of 100% stainless steel and Ni-based alloy steel parts can be manufactured; in 2003, the launch of large-size rapid prototyping equipment AFS-450, hardware and software than the AFS-320 has 22 major improvements. The equipment is more stable, reliable, user-friendly, faster and more accurate, and has become the preferred equipment for enterprise users;

In 2005, AFS-500 was introduced with molding size of 125 liters and sales were formed in the same year. A sintered fine casting wax that can be directly steam removed was also introduced, which seamlessly connects with traditional investment casting and solves the problem of rough surface of titanium alloy rapid casting;

In 2008, we developed the AFS-700 molding machine, with a molding size of 245 cubic liters, which was the largest laser powder sintering machine at that time, and met most of the requirements for precision casting size. The equipment adopts a new way of loading and spreading powder, which reduces the unidirectional spreading time by half and eliminates the need for intermediate feeding. The equipment was sold in the same year;

In 2009, a breakthrough was achieved in laser sintered sand. The strength and gas generation of the molded sand core reached the casting requirements. Started the development of casting sintered sand sintering molding of proprietary equipment laser core making machine;

In 2010, the development of LaserCore 5300 prototype was completed and test marketing started.

3D printing technology, as one of the most advanced manufacturing methods, also represents the most cutting-edge science and technology in the world today.

However, the development of science and technology industry is not overnight, must be after a long and arduous accumulation, there will be an outbreak, after nearly 20 years of cultivation and progress, Beijing Longyuan finally ushered in the outbreak of the 3D printing industry.

3D Applications Leading China

　　Since the outbreak of the global economic crisis caused by the financial crisis in the United States in 2008, the world economy seems to have never come out of the doldrums, and despite several attempts to rebound during that period, growth has ultimately been weak due to a lack of strength. Historical experience has repeatedly shown that when the global economy is in recession, it is the time for the emergence of a new economy and the birth of new technologies. The sluggishness of the global economy showed that the traditional relations of production had seriously impeded the development of productive forces and that change would be the new driving force of those relations.

　　This year, the discussion of the third industrial revolution has reached a climax. American scholar Jeremy Rivkin said that the combination of the Internet and new energy sources will produce a new round of industrial revolution - this will be the third "revolution" after the 19th-century steam engine and 20th-century electrification. The Economist magazine also pointed out that the market potential of 3D printing technology is huge, and it is bound to become one of the many breakthroughs that will lead the future trend of manufacturing. These breakthroughs will enable factories to say goodbye to traditional tools such as lathes, drills, stamping presses and mold-making machines, and be dominated by more nimble computer software, which is a sign of the arrival of the third industrial revolution.

　　As an advanced manufacturing technology integrating light/machine/electricity, computer, numerical control and new materials, 3D printing technology is now widely used in aerospace, and weapons, automotive and racing cars, electronics, biomedical, dental, jewelry, gaming, consumer goods and daily necessities, food, construction, education and many other fields. It is foreseeable that the technology will be more inclined to the direction of daily consumer goods manufacturing, functional parts manufacturing and integrated manufacturing of tissues and structures.

　　After 19 years of exploration and innovation, Beijing Longyuan has become a leader in the application of 3D printing technology in China, and has made outstanding contributions to the take-off of China's aerospace, automotive, and other industries.

　　Aerospace field: Aerospace products are characterized by complex shape, small batch size, large differences in part specifications, high reliability requirements, and the stereotyping of the products is a complex and precise process, which often requires many times of design, testing and improvement, costly and time-consuming, and it is difficult to manufacture by traditional methods. Therefore, 3D printing technology has a unique application prospect in the research and development of modern aerospace products with its flexible and various process methods and technical advantages. In foreign countries, the United States, Boeing will be 3D printing technology and traditional casting technology, manufacturing aluminum alloy, titanium alloy, stainless steel and other different materials such as cargo door bracket parts; General Motors application of 3D printing technology to manufacture aerospace and marine impeller and other key parts; Belgium Materialise company's Mammoth laser rapid prototyping system, its one-time maximum processing size Mammoth laser rapid prototyping system of Belgium Materialise Company, its one-time maximum processing size of up to 2200mm.

　　In China, Beijing Longyuan, relying on its own technical advantages, provides China's aerospace and other sectors and aircraft manufacturers with the production and service of helicopter engines, helicopter magazines, worm gear pumps, titanium frames, exhaust ducts (maximum height up to 2800mm), aircraft suspension parts, flywheel shells and other aircraft parts: in 1996, the first commercialized SLS rapid prototyping machine was sold to the Beijing Institute of Aeronautical Material Research In 1996, the first commercialized SLS rapid prototyping machine was sold to Beijing Aeronautical Material Research Institute (BAMRI), and was successfully applied to the development of new products for military aviation; in 1999, the second generation of commercialized equipment, AFS-320, was successfully introduced to the market. The application of rapid prototyping has gradually unfolded, and it has participated in and completed the development of several key national aerospace projects, such as: liquid oxygen-kerosene and liquid oxygen-liquid hydrogen engines for high-thrust rockets, and satellite gyroscope frames.

　　Military industrial field: 3D printing technology and traditional manufacturing technology, compared with simple, easy to operate and so on, especially for some new materials processing, the results are particularly significant. Such as aluminum alloy has been the most widely used metal structure material in the military industry. Aluminum alloy has the characteristics of low density, high strength, good corrosion resistance, high temperature resistance, etc. As a structural material, due to its excellent processing performance, it can be made into a variety of cross-sectional profiles, tubes, high-bar plates, etc., in order to give full play to the potential of the material, and to improve the stiffness of the components. Therefore, aluminum alloy is the lightweight structural material preferred for weapon lightweighting. The U.S. military has applied 3D printing technology to assist in the manufacture of pop-up igniter models for missiles, and has achieved good results.

　　In China, titanium alloy has been widely used in the manufacture of self-propelled artillery turrets, components, armored vehicles, tanks, military helicopters, etc. In 1999, Beijing Longyuan Automatic Forming Co., Ltd. participated in the completion of a number of key national military industry projects by using 3D printing technology, such as the turbocharger of the new JS-II tanks, the shells of infrared guidance instrument observation mirrors, etc. In 2002, Beijing Longyuan began to carry out research on high-power laser direct manufacturing of metal parts with the China Academy of Engineering Physics, thus further promoting the development of China's military industry. In 2002, Beijing Longyuan started to carry out research on high-power laser direct manufacturing of metal parts with China Academy of Engineering Physics, which further promoted the development of China's military industry.

　　Automobile manufacturing field: Germany's Audi Automobile Company (Audi) used 3D printing technology to successfully use KUKA robots to manufacture the Audi RSQ car. With the development of China's automobile industry, the rapid growth of automobile production, some key components are also increasingly complex, large-scale and lightweight, which requires the realization of the parts of the overall and integrated manufacturing. The use of molds for sanding the traditional process of mold making, making the mold more and more complex, the number of live blocks has also increased dramatically, these factors to a certain extent have constrained the development of China's automotive industry.

　　In China, the technical team of Beijing Longyuan, a leader in 3D printing technology in China, has launched a research on 3D printing technology in the field of automotive engine manufacturing. SLS uses infrared laser beams to melt thermoplastic materials to form three-dimensional parts, and one of its most important features is that the molding process is independent of the degree of complexity, which makes it particularly suitable for the extremely complex internal structure of the engine block, cylinder head, intake and exhaust pipes and other components. components. In addition, SLS technology molding materials, especially with casting resin sand and disappearable mold material molding, therefore, can be combined with casting technology, rapid casting of engine parts. the combination of SLS technology and casting technology, derived from the rapid casting technology, can be effectively applied to engine design and development stage of the prototype of the rapid manufacturing. Its suitability for single-piece and small batch trial production and production characteristics, can quickly respond to the market and provide small quantities of products for testing and experimentation, help to ensure the speed of product development. The controllability of its molding process allows for instant modifications at low cost during the design development stage in order to check designs or provide assembly models. Helps to improve the quality of product development, its rapid prototyping raw material diversity, for the product development stage provides different process combinations, due to the localization of SLS raw materials and molding process can be organically combined with the traditional process, which helps to reduce the cost of development, the combination of the rapidity of the process, to support the increase in the frequency of the product replacement, and help to promote the product to enter the market as soon as possible.

　　Using 3D printing technology, Beijing Longyuan produces engine blocks, cylinder heads, gearbox shells, etc. for automobile manufacturers, which are not only fast but also highly accurate, thus making the manufacture of complex automobile parts digital, precise, flexible and green. Nowadays, Longyuan's products can be seen in the engines of many domestic high-speed railroads, moving trains and subways.

　　In 2001, Beijing Longyuan developed successful rapid prototyping and additive manufacturing processes for key structural components of automobiles, and began to provide RP services for cylinder blocks, cylinder heads, intake pipes, and transmission housings for automobile companies;

　　In 2006, Beijing Longyuan laser direct molding casting sand core technology to the market, the sale of the first specialized for casting sand core molding equipment. And successfully used in the rapid development of automobile engine block, cylinder head and supercharger;

　　In 2011, Beijing Longyuan started to research and develop large-size laser core making machine to meet the needs of diesel engine and other industries; through the cooperation with Guangxi Yuchai Machinery Co., Ltd. and Dongfeng Commercial Vehicle Crafts Institute, it has developed the rapid manufacturing method and process of diesel cylinder block and cylinder head, and so on.

　　Biomedical field: At present, 3D printing technology is also applied to the biomedical field, including bones, teeth, artificial liver, artificial blood vessels, drug manufacturing and so on. In terms of bio-manufacturing, developed countries such as Europe and the United States have more research, a wider range and have achieved clinical applications: in the United States, the use of SLA manufacturing technology, the use of biocompatible resins can be made for medical hearing aids, eye crystal models, artificial teeth, etc.; in Italy, the use of SLA manufacturing technology has been manufactured using the human skeletal restorations.

　　In China, Beijing Longyuan cooperates with Peking University Stomatological Hospital, where the CT scan data of patients are processed by Magics software from CT workstation to PC, burned and stored in standard format (Dicom format), and then provided to Longyuan, which develops and researches the rapid prototyping machine AFS-320 accordingly. This equipment adopts the selective laser powder sintering method, and the raw material is polystyrene powder, which is made into a solid model, and can be used in oral healthcare for symptoms such as abnormal zygomaticomandibular bone fiber hyperplasia and other symptoms, and has achieved very good curative effects. Meanwhile, in the treatment of old zygomatico-zygomatic arch comminuted fracture, the results of clinical application showed good therapeutic effect.

Rigorous management in pursuit of excellence

　　At present, many countries and regions in the world are developing or applying 3D printing technology. According to some information, in 2010, the total output value of the global 3D printing industry reached 1.325 billion U.S. dollars, an increase of 24.1% over the previous year; in 2011, the global revenue was 1.7 billion U.S. dollars, an increase of 2.94% over the previous year; it is predicted that it will reach 2.1 billion U.S. dollars in 2012, 3.7 billion U.S. dollars in 2015, and 6.5 billion U.S. dollars in 2019. It can be said that the number of 3D printing technology to a certain extent shows the country's economic vitality and innovation ability.

　　According to the international authoritative 3D printing industry report "Wohlers Report 2012", the world's major countries and regions according to the number of equipment owned by the top 10 rankings are as follows: the United States 38.3%, Japan 10.2%, Germany 9.3%, China 8.6%, the United Kingdom 4.4%, Italy 3.9%, South Korea 2.2%, Canada 1.9%, China Taiwan 1.5%. TP3T, France 3.0%, South Korea 2.2%, Canada 1.9%, China Taiwan 1.5%, of which the U.S. and the EU is the most important equipment owning countries, China has less than 10% of the number of equipment, and many of them are imported from abroad. And the production equipment of major countries and regions equipment manufacturers are as follows: the United States 72.9%, Europe 10.2%, Israel 9.3%, Japan 3.7%, China 3.6%, and the remaining 0.3% is owned by other countries and regions. The above data shows that China still needs to catch up in 3D printing.

　　Among the few domestic enterprises in the 3D printing industry, Beijing Longyuan is undoubtedly an industry leader. In the course of nearly twenty years of development, Beijing Longyuan has also experienced the experience that all new technology industries are bound to go through. As the earliest domestic realization of 3D printing technology (additive manufacturing technology) industrialization, service-oriented listed companies, Beijing Longyuan not only has excellent technical strength, in the management also has excellent. The company has a stable and effective team, from the chief engineer Feng Tao, marketing director to the technical backbone, etc., are the old staff since the start of the business, they have comprehensive professional knowledge, professional and technical skills, rich market experience, with good collaboration and communication skills, can be in-depth and accurate grasp of the customer's product design, development and production requirements, through the scientific and rigorous workflow, combined with the long-term practical experience to provide users with the most suitable solutions. Through scientific and rigorous workflow, combined with long-term practical experience, we can provide the most suitable solutions for our customers.

　　Beijing Longyuan not only has independent intellectual property rights of 3D printing equipment and products, but also has a unique service system. We provide one-stop solution to our customers. The company has the domestic top equipment, can provide a complete set of equipment and services for small batch production, as well as personalized customization services, to achieve the true meaning of one-stop processing to solve the problem. At the same time, the use of comprehensive technology and strong technical strength, for the different stages of product design and development, to provide the best equipment and technical means, to provide customers with the shortest time, the lowest cost, the best performance of products and services.

　　Beijing Longyuan has many types of self-developed SLS-type series 3D printers, processing materials including paraffin, polymer, metal, ceramic powder and its composite powder, etc. Its products are fully in line with the requirements of customers in aerospace, automobile manufacturing and other high-precision fields.

　　In terms of service, Longyuan's performance is more professional. Longyuan provides customers with 24-hour online consulting services, and has branches or offices in many parts of the country. Whenever and wherever problems or difficulties are encountered, Longyuan's engineers will provide assistance through the network, telephone or door-to-door. At the same time, Longyuan requires every after-sales service personnel to master the relevant technical and theoretical knowledge, and be able to carry out after-sales technical training and maintenance, to solve the customer's use of the problem, to maintain a good relationship with the customer. For example, the service personnel should know how to operate CAD drawing operation, in order to provide customers with timely and effective technical support and after-sales service. In addition, Longyuan's after-sales service personnel are all professionals with bachelor's degree or above in related majors, such as mechanical, electromechanical, electronic, material application, etc., and also have a certain amount of work experience.

Continuous innovation and sailing for the future

　　For the world in the 21st century, this is an era when "Made in China" is ubiquitous. 2010, China surpassed the United States to become the largest country in the manufacturing industry, with the share of manufacturing output accounting for 19.8% in the world. of the 22 major categories of the manufacturing industry, our country ranked first in the world in seven of the major categories. "Made in China" has made great contributions to China's economic takeoff and the development of the world economy. However, China has a long way to go to become a manufacturing powerhouse and change the status quo of being in the middle and low end of the international division of labor and industrial chain.

　　The arrival of the wave of 3D printing industry is an excellent opportunity. The third industrial revolution centered on the digitalization and intelligence of the manufacturing industry is coming - the connotation of advanced manufacturing technology innovation includes product innovation, manufacturing technology innovation and industrial model innovation. Digital, intelligent technology will profoundly change the manufacturing production mode and industrial form, will bring unprecedented challenges and opportunities for China's manufacturing development, the next two decades, will be China's manufacturing industry from big to strong, to achieve leapfrog development, innovation and comprehensive competitiveness to enter the world's forefront of the excellent development opportunities.

　　Beijing Longyuan continues to stand in the tide of China's 3D printing industry, on the one hand, advocating the development of the industry, successively initiated the establishment of the "Beijing Digital Manufacturing Industry Technology Innovation Alliance" and "China 3D Printing Technology Industry Alliance", and at the same time invested in the research and development of newer and higher-end technologies and products. At the same time, it invests in R&D and production of newer and higher-end technologies and products. According to Feng Tao, Chief Engineer, Beijing Longyuan is working on the application of metal powder in SLS technology and has achieved certain results. In his opinion, realizing the use of high melting point metal direct sintering molding parts is of particular importance for the wider application of 3D printing technology in high strength parts that are difficult to manufacture by traditional cutting and machining methods. Feng Tao believes that the research direction of SLS forming technology in the field of metal materials should be the sintering molding of unit system metal parts, the sintering molding of multiple alloy material parts, advanced metal materials such as metal nanomaterials, amorphous metal alloys, such as laser sintering molding, etc., is particularly suitable for the molding of micro components of cemented carbide materials. In addition, parts with functional gradient and structural gradient are sintered and formed according to the specific functional and economic requirements of the parts. It is foreseeable that, with the mastery of laser sintering metal powder molding mechanism, the optimal sintering parameters of various metal materials to obtain, as well as the emergence of special rapid prototyping materials, the research and references of SLS technology will certainly enter a new realm.

　　In addition, Beijing Longyuan Institute also has a newer application direction in the medical field, i.e., professional rapid prototyping and rapid manufacturing solutions in the dental field: CAD design of dentures can be realized by using specific CAD software, including 3D design of tooth bases, crowns, bridges, hooded crowns, veneers, inlays and so on. With CAD design, rapid prototyping and rapid manufacturing of dentures can be automated, with high results, fewer consumables and lower costs.

　　As one of the most typical and widely used technologies in the digital manufacturing industry, 3D printing technology will play an unparalleled role in upgrading China's industrial manufacturing industry. This kind of innovative technology, which has a series of strategic advantages such as broad market prospects, low resource consumption, large driving factor, many employment opportunities, and good comprehensive benefits, will help to cultivate strategic emerging industry clusters, as well as promote and upgrade a number of key industry clusters.

　　Undoubtedly, the promotion of 3D printing technology is of great strategic significance to enhance China's industrial innovation capability, improve process manufacturing capability, drive the development of related industrial chain, crack the industrial development and resource environment dilemma, cultivate new industries and optimize industrial structure.

　　Beijing Longyuan, in the 3D printing industry on the road, but also continue to stride forward.