In July this year, the total investment of more than 1 billion yuan of the Land Wheels production line was put into trial operation in Fuzhou, Jiangxi Province.This is the first domestic and international digital continuous automated forged aluminum wheel production line, marking the achievement of the "four-dimensional manufacturing" project of Demarco, which has undergone eight years of research and development, entering the industrialization stage.

Four-dimensional manufacturing is a method of working that is formed on the basis of traditional three-dimensional manufacturing with the use of force offset and balance principles, introducing a new dimension of mechanical considerations.

Starting from the transformation of equipment, technology, and process, the "four-dimensional manufacturing" innovation and transformation of traditional equipment such as forging presses effectively achieves energy conservation, emission reduction, and green manufacturing

Taking the forged aluminum wheel production line as an example, the series of equipment using the "four-dimensional manufacturing" technology all adopt symmetrical integrated structure and modular production, with force and torque cancellation of nearly 100%, which can reduce vibration amplitude by 75%, energy consumption by 80%, improve rigidity by 4 times, accuracy by 4 geometric orders, and production efficiency by 10 times. The comprehensive benefits of performance, energy conservation, environmental protection, etc. can be increased by 10 times.

By Yu Xue and Chen Yan, reporters of the news magazine Outlook

The four-station spinning machine developed using the "four-dimensional manufacturing" technology saves 75% of material, weighs 25% of traditional equipment, costs 25% of traditional equipment, and improves work efficiency by four times.The picture shows the new spinning machine in production operation. Huang Ruipeng

The wheel hub is the rotating part of the wheel core connected by the column of steel in the inner profile of the car tire, which plays a role in bearing, steering, driving, braking, etc. It is one of the important components of the car.

In July this year, the production line of the Land Wheels with a total investment of over 1 billion yuan was put into trial operation in Fuzhou, Jiangxi Province.As a demonstration project of the "Four-dimensional Manufacturing" project, this digital continuous automation forging aluminum wheel production line marks the achievement of the "Four-dimensional Manufacturing" project of Derma after 8 years of research and development.

Four-dimensional manufacturing is a working method based on traditional three-dimensional manufacturing, which uses the principle of force offset and balance to introduce a new dimension of mechanical considerations, forming a four-dimensional manufacturing method.

Li Wenlong, chief engineer and chief scientist of Derma Company, said that the "four-dimensional manufacturing" technology focuses on the transformation and iteration of high-end equipment and industrial mother machines, and precisely targets energy conservation, emission reduction, and lightweighting in the automotive industry. It breaks away from traditional thinking and path dependence, and achieves breakthroughs in basic theories and technical methods.

At present, the "Four-dimensional Manufacturing" R&D team has completed the basic theoretical demonstration, topological data evaluation, the production of the first set of equipment, and the combination of scene-based simulation pipelines. It has obtained 125 domestic and foreign patents, including 58 invention patents, in 15 countries and regions such as China, the United States, Japan, and the European Union.

Innovatively propose the "four-dimensional manufacturing" working method

The investor of the "Four-dimensional Manufacturing" project is Ningbo Jingyi Micro-shaft Co., Ltd. (hereinafter referred to as "Jingyi Company").This company is famous for producing and exporting micro-shafts. Over the past decades, it has produced more than 10 billion micro-shafts (sets) and exported them to more than 30 countries and regions such as the United States, Europe, and Japan. The blue light intelligent energy-saving window developed by its investment fills in many domestic and international gaps with advanced concepts.

Develop high-end special equipment to adapt to the development trend of lightweight automobiles.In 2010, Dong Xiangyi, Chairman of Jingyi Company, found during his inspection in the United States that the wave of lightweight automobiles was rising and spreading in developed countries and regions such as Europe, America and Japan. Among them, the trend of replacing steel and cast aluminum wheels with forged aluminum wheels appeared in the metal parts of the inner tire, while China was just starting.After returning to China, Dong Xiangyi and the management team of the company conducted research and demonstration, and established Ningbo Dermar Intelligent Machinery Co., Ltd. in early 2015, focusing on scientific research and equipment development.

After investigating several domestic automotive wheel hub manufacturers, the team of Derma found that the equipment technology and manufacturing process of these enterprises are relatively traditional, with high energy consumption, scattered production processes, and high cost risks, making it difficult to adapt to the application and promotion of large-scale industrialization in the future.Therefore, Derma proposed to learn from the experience of lean micro-shafts and blue-ray energy-saving windows, take the research and development of high-end special equipment as the early breakthrough, and embark on a unique path of intelligent manufacturing transformation and upgrading.

Innovatively proposing the "four-dimensional manufacturing" working method to assist in the transformation and upgrading of intelligent manufacturing. Huang Jin, Deputy General Manager of Derma Company, said that forging alloy aluminum wheels requires an efficient and high-power dedicated forging press. When disassembling and dissecting the original equipment components, it was found that the true force point of the 10000 ton forging press is on the 4 screws and 8 nuts inside the column. It relies on the tightening force of the screw nuts to resist the processing pressure, and the forging press itself also has to withstand the rebound force of the forging impact.

When studying the improvement of equipment structure, Dong Xiangyi proposed to cancel the four columns and design the forging press as two or four stations using the force offset and balance theory.At that time, the team faced a dilemma - could the idea of introducing Newtonian mechanics dimensions be theoretically justified?

The Dermar team invited experts and professors, senior engineers to demonstrate that the introduction of force compensation and balance principle in the field of machine tool equipment and industrial machine research and development has scientific basis. From the perspective of technical conditions and implementation path, China's existing equipment technology conditions and digital manufacturing capabilities are also sufficient to support.After extensive discussions, the idea was finally named the "four-dimensional manufacturing" method, and efforts were made to tackle key problems in high-end professional equipment and forged aluminum wheel production lines.

Starting from the transformation of equipment, technology, and process, the "four-dimensional manufacturing" innovation and transformation of traditional equipment such as forging presses effectively achieves energy conservation, emission reduction, and green manufacturing.Forging alloy aluminum wheels requires high-efficiency and high-power dedicated forging presses. Li Wenlong turned a 16-meter-high, 1,000-ton vertical forging press onto its side, turning it into a 2-meter-high, horizontal forging press, achieving balanced force on all four legs of the forging press and improving the stability factor.

At the same time, the team changed the shape design of the forging machine to an olive shape with smooth lines and beautiful appearance, cleverly installing two symmetrical workstations, greatly improving work efficiency. "Traditional equipment is rectangular or square, with many weak stress links, making the equipment design appear bulky and robust. Now, we use elliptical or olive shaped forging machines to evenly distribute the force on the entire machine, which can greatly reduce material loss and energy consumption." said Li Wenlong.

The workload of the dual-station horizontal lying forging press is equivalent to the efficiency of two traditional forging presses.The original machine weighs 2,000 tons, while the new forging press using the "four-dimensional manufacturing" technology has a total weight of 120 tons, including the reinforced steel ring, which is equivalent to 6% of the original machine weight, and the compressive strength is increased by 5 times.The equipment assembly components have been reduced from more than 200 to more than 30, making manufacturing and assembly more convenient.

The Derma team has invited professionals to evaluate the comprehensive functionality and ergonomics of four-dimensional manufacturing technology. Taking the production line of forged aluminum wheels as an example, the series of equipment using "four-dimensional manufacturing" technology adopts a symmetrical integrated structure and modular production, with nearly 100% force and torque cancellation, which can reduce amplitude by 75%, energy consumption by 80%, improve rigidity by 4 times, accuracy by 4 geometric levels, increase production efficiency by 10 times, and comprehensive benefits such as performance, energy conservation, and environmental protection can be improved by 10 times.

Make the machine tool equipment fine and detailed

According to traditional technology and process, to match the processing capacity of the assembly line forging press, it is necessary to configure four single-station spinning machines, which is costly and inefficient."We adopted the 'four-dimensional manufacturing' technology and successfully developed a balanced and symmetrical four-station new spinning machine, which can save 75% of materials, with a price equivalent to 25% of the original equipment, and the work efficiency is improved by four times," said Huang Jin.

The initial effect of the new equipment did not meet the target.R&D personnel invited Wang Jun, a senior technician from China Baowu, and several experts to demonstrate that there was no problem with the structural design of the new equipment, but there were flaws in the process guidance and insufficient motor torque.Several experts replaced the original ordinary motor with insufficient spindle power with a high-power motor, and installed servo motor drives at each workstation, effectively solving the efficiency problem of the spinning machine.

Technological research and development cannot be separated from the great collaboration between industry, academia, and research. In recent years, Derma has integrated various resources and created a cross industry and academia industry university research community, covering universities such as Zhejiang University, Fudan University, Shanghai Jiao Tong University, Xi'an Jiao Tong University, Beijing University of Science and Technology, Tianjin University, as well as leading manufacturing enterprises such as China FAW, China Yizhong, Ansteel, Baowu Group Baosteel Co., Ltd., Jingda Equipment, China Society of Mechanical Engineering, China Machinery Intelligent Equipment Association, and China Academy of Intelligent Industries, And engineering and research personnel from industry authoritative institutions.

The shaping of automotive wheel hub products is completed by the milling process. Traditional milling machines are mostly single arm overhanging structures, with an arm length of 50 to 100 centimeters. The larger the wheel hub size, the longer the overhanging arm, and the easier it is for the center of gravity to tilt. In order to maintain equipment stability, the self weight needs to reach one or two to three tons or more. Chen Zhen, the Technical Director of Derma, said that the basic equipment structure of the single cantilever center of gravity tilt system results in poor processing stability, which prevents the spindle speed from increasing. In addition, the milling feed depth is limited, and the surface accuracy of the product can only reach level 7, which is equivalent to semi-finished products, and further polishing treatment is required.

Based on "four-dimensional manufacturing" technology, the Derma team has changed the milling machine tool from a single arm overhanging structure to a double arm riding design, with the machining arms extending towards both ends of the machine position. Chen Zhen said that in this way, the milling cutters on both sides rotate simultaneously, and the center of the spindle falls at the middle point. The vibration stress generated during processing is offset, effectively ensuring the stability of equipment operation and greatly reducing the self weight component.

The application of new technologies has brought significant results. The spindle box of the milling machine tool originally weighed 1 ton, but now it has been reduced to 200 kilograms, with a material saving rate of 80%; The original maximum spindle speed was 7000 revolutions per minute, but now it has increased to 17000 revolutions per minute; The milling depth has increased from 2 millimeters to 8 millimeters, and the surface accuracy exceeds that of the grinding machine, even reaching level 11 in the grinding process.

In July this year, the Land Wheels hub production line with a total investment of over 1 billion yuan was put into trial operation in Fuzhou, Jiangxi. As a demonstration project of "four-dimensional manufacturing", this digital, continuous, and automated forged aluminum wheel production line marks the industrialization stage of the Derma "four-dimensional manufacturing" project, which has undergone 8 years of research and development.

"Four dimensional manufacturing" is a work method formed by applying the principles of force opposition and balance, and introducing new dimensions of mechanical considerations on the basis of traditional three-dimensional manufacturing.

Li Wenlong, Chief Engineer and Chief Scientist of Derma Company, said that the "four-dimensional manufacturing" technology focuses on the transformation and iteration of high-end equipment and industrial mother machines, with the precise goal of energy conservation, emission reduction, and lightweighting in the automotive industry. It breaks away from traditional thinking and path dependence, and achieves breakthroughs in basic theories and technical methods.

At present, the research and development team of "four-dimensional manufacturing" has completed basic theoretical demonstration, topology data evaluation, production of the first set of equipment, scenario based simulation assembly line combination and other research and development goals. It has obtained 125 domestic and foreign patents, including 58 invention patents, in 15 countries and regions such as China, the United States, Japan, and the European Union. 

The first domestically and internationally to adopt "four-dimensional manufacturing" technology, with fully independent intellectual property rights, a fully automatic continuous forged aluminum wheel production line, and an annual production of 1.5 million automotive wheels. The picture shows the fully enclosed green intelligent machining center assembly (taken in November 2023) by Huang Ruipeng

Promote innovation and iteration of the "national treasure"

The high-end machine tools that advanced manufacturing relies on are known as the "national treasure" of industrial mother machines. China is the world's largest producer, importer, and consumer of industrial mother machines, but in the past, China relied on imports for high-end specialized CNC machine tools and key components.

According to Professor Cang Daqiang from the School of Metallurgy and Ecology at Beijing University of Science and Technology, aerospace, ocean going vessels, nuclear industry, automobiles, high-speed rail, military industry, mines, and tunnel shield tunneling machines all require large or ultra large high-precision intelligent machinery. Currently, there are still many relying on imported equipment and technology, and there is an urgent need to innovate theories and develop new equipment technologies.

Several industry experts believe that the basic theory and core technology of Derma's "four-dimensional manufacturing" technology can be widely applied in high-end equipment "industrial mother machines" and advanced manufacturing industries, especially in the high-precision specialized equipment and high-end machine tool industries.

On the one hand, innovation breaks through basic theories and injects fresh water into the design and manufacturing of mechanical equipment. Cang Daqiang believes that the basic theoretical innovation of Derma's "four-dimensional manufacturing" lies in its application of force and reaction force, even number multiplication principle, breaking the traditional cognition of mechanical equipment design and manufacturing, providing new ideas and approaches for the improvement, iteration, and green transformation of high-end equipment and industrial mother machines.

According to data, the Derma horizontal forging machine saves 94% of materials and improves work efficiency by 5 times; The integrated milling machine tool saves 80% of materials, increases equipment rigidity by 4 times, milling accuracy by 4 times, and reduces overall energy consumption by 50%. Some equipment even drops by 80%. According to third-party evaluations, the comprehensive benefits of the Derma forged aluminum wheel hub demonstration production line, including material conservation, energy conservation, green environmental protection, and performance quality, have increased by 10 times compared to traditional technological equipment.

On the other hand, promoting the innovative application of technology provides important technical support for the research and manufacturing of advanced equipment. Yan Shanwu, an expert from the China Forging and Pressing Association, said that Derma's "four-dimensional manufacturing" technology can be applied to various high-end CNC machine tools such as turning, cutting, forging, and milling, as well as special machining machines and specialized machining centers. It can be said that it applies innovative technology to the production field of high-end products and makes practical demonstrations, not only developing advanced equipment, but also manufacturing excellent products.

Currently, intelligence, precision, and lightweight have become a major trend in the CNC machine tool industry.

On the Derma Land Wheels production line, the CNC machine tool with multi axis, multi station, and integrated turning and milling in the machining center is equipped with 4 stations, 8 turrets, and 4 main axes with 16 secondary axes, ensuring stable operation and seamless connection. At the same time, the surface processing accuracy exceeds the grinding process, with an error of only 0.2 micrometers, which is equivalent to 2% of human hair.

Professor Lv Zhengyu from the School of Electrical Engineering at Zhejiang University said that the Derma team has introduced topology, established a data simulation model, and integrated robots into the entire production scene through digital calculation and pre control. They can track and switch various process flows and technical links on the streamline in real-time, reflecting an important breakthrough in the transformation and iteration of intelligent manufacturing.

At Fuzhou Land Wheels Hub Manufacturing Co. ,Ltd., the Derma Land Wheels wheel hub production line has started trial operation. This is the first domestically and internationally dedicated production line for forged aluminum wheels with fully independent intellectual property rights, which realizes raw material cutting, low-temperature forging, spinning and shaping, as well as one-time turning and milling, and digital automation. The production time for a single product is 15 seconds, and the annual production of 1.5 million automotive wheels is achieved.

"Compared to enterprises of the same investment scale, Land Wheels has significant advantages in terms of site area and labor costs." said Sang Jianguo, General Manager of Fuzhou Land Wheels Hub Manufacturing Co. ,Ltd. This production line covers an area of 20 acres, with a factory area of 10000 square meters, which is one tenth of that of peer enterprises. The annual average tax revenue per acre can reach 10 million yuan. In terms of labor costs, traditional equipment requires 800 to 1000 operators, while Land Wheels only needs 40 to 50 management personnel.

In the future, the Derma team will use new technologies and equipment to assist in the upgrading and transformation of industrial parks and clusters in various regions. Huang Jin said that we will use market-oriented methods to build a "four-dimensional manufacturing" technology town through technological cooperation, investment co construction, equipment leasing, etc., to provide efficient and cost-effective one-stop technical services for small and medium-sized enterprises in mold design, product research and development, and finished product delivery.

(Outlook, Issue 47, 2023)