The progress of China's three-dimensional warehouses
1. Background introduction
The emergence and development of three-dimensional warehouses are the result of the development of production and technology after the Second World War. In the early 1950s, three-dimensional warehouses using bridge-type stacking cranes appeared in the United States; in the late 1950s and early 1960s, three-dimensional warehouses with driver-operated lane-type stacking cranes appeared; in 1963, the United States took the lead in using computer control technology in elevated warehouses and established The first computer-controlled three-dimensional warehouse was built. Since then, automated three-dimensional warehouses have developed rapidly in the United States and Europe, and formed a specialized discipline. In the mid-1960s, Japan began to build three-dimensional warehouses, and the development speed is getting faster and faster, becoming one of the countries with the most automated three-dimensional warehouses in the world today.
my country’s development of three-dimensional warehouses and material handling equipment was not late. In 1963, the first bridge-type stacking crane was developed (Beijing Hoisting and Transportation Machinery Research Institute of the Ministry of Machinery), which began in 1973. Developed my country's first computer-controlled automated three-dimensional warehouse (15 meters high, responsible for the Hoisting Department of the Machinery Department), which was put into operation in 1980. As of 2003, the number of automated three-dimensional warehouses in my country has exceeded 200. Three-dimensional warehouses have become an indispensable warehousing technology for enterprise logistics and production management due to their high space utilization, strong entry and exit capabilities, and the use of computers for control and management, which are beneficial to enterprises in implementing modern management. Enterprise's attention. With the rapid development of science and technology, information technology, automated production technology and commercialized economy, the handling, storage, distribution and corresponding information of raw materials, semi-finished products, finished products and various materials in the circulation link are no longer an isolated process. things. In fact, in the development process from Manufacturing Resource Planning (MRPⅡ) to Enterprise Resource Planning (ERP), all aspects of logistics have completed their integration process. Automated warehousing, logistics and information flow have become key nodes in organizing production, connecting production, sales, and management networks, and are playing an increasingly important role in the national economy as an important means of reducing logistics costs. my country's first fully automated three-dimensional warehouse, the Beijing Automobile Manufacturing Plant Automated Three-dimensional Warehouse, was developed and produced by the Beijing Hoisting and Transportation Machinery Research Institute. After the automated three-dimensional warehouse was applied in my country in the 1980s, it developed rapidly and was widely used in the 1990s. For more than 20 years, Beijing Crane Institute has designed and manufactured more than 100 sets of various forms of automated three-dimensional warehouses. The products are widely used in machinery, metallurgy, chemical industry, medicine, military industry, food, transportation and electronics industries, leading and promoting The development and application of logistics technology in my country. In 2000, Beijing Crane Institute completed the largest fully automated three-dimensional Coulomb library with the highest technical level produced in my country to date - Lenovo Computer Company's integrated logistics system. Lenovo's logistics system integrates the latest international three-dimensional warehouse technology, and the entire system adopts about 30 new technologies. The lane stacker is one of the key equipment of the three-dimensional warehouse system. It includes more than 10 new technologies such as operating speed regulation technology, laser ranging technology, fork speed regulation technology, lifting mechanism address recognition technology, and variable cross-section column technology. All are my country's latest research and application results or internationally advanced technologies. The conveyor equipment adopts a number of new technologies such as combined structure, cantilever lifting platform and automatic pallet collection technology. The distribution vehicle adopts the latest research results in terms of operation adjustment and address recognition. The adoption of dual-vehicle avoidance technology allows the distribution vehicle to achieve higher capabilities than the design requirements. The shelf structure adopts finite element analysis. The surface treatment adopts a new surface spraying process, which is beautiful and durable. The control system adopts PROFIBUS fieldbus control technology, and its high integration with the R/3 system reflects the breakthrough achievements of this three-dimensional warehouse system in integrating with large-scale information systems. Lenovo's automated logistics system is an internationally advanced product independently developed by my country. The successful operation of the system marks a new level of my country's logistics automation technology.
2. Current status of technology
A relatively complete automated three-dimensional warehouse system mainly includes:
(1) Storage and turnover of goods - high-rise shelves and pallets, Cargo boxes;
(2) Inbound and outbound operations—stacking cranes;
(3) Inbound and outbound distribution systems—roller, chain conveyor, distribution truck , lifts, etc.;
(4) Automatic control system - including computer-controlled entry and exit equipment, distribution systems and all electronic control devices of various testing and insurance institutions;
(5) Computer management system - warehouse account management, data analysis, reasonable management of cargo locations, status display of equipment operation and inventory status, etc. Management system and control system are networked.
(6) A stacker crane can be used in several lanes of a three-dimensional warehouse with low frequency of entry and exit. In this case, stacker crane transfer equipment (such as a transfer car) should be equipped.
The technical status of the main equipment of my country's automated three-dimensional warehouse is roughly as follows:
1. High-rise shelves, pallets, and containers
High-rise shelves are the core components of automated three-dimensional warehouses Main structure part. Generally, the steel structure is welded or assembled. Each row of shelves is divided into several columns and layers of unit cargo compartments, and each cargo compartment generally stores 1-3 pallets (cartons). At present, the high-rise shelves manufactured in China are generally less than 20 meters, and most are 10-15 meters. Shelves are made of steel, and welded shelves mostly use hot-rolled steel. Prefabricated shelves mostly use thin cold-rolled steel. Welded construction is strong and durable, but bulky. The assembled appearance is beautiful, the disassembly and assembly performance is good, and the transportation is convenient. Due to the good mechanical properties of the cold-rolled thin-walled steel section, it is lightweight and saves steel, reducing costs and has great potential. If the connector parts are designed very reasonably and firmly, this is the development direction of high-rise shelves. The design of the shelf structure generally uses a corbel-type structure when the pallet (cargo box) is large in size, and one pallet (cargo box) is stored in each cargo compartment. When the pallet size is small, a beam-type structure is used. Each cargo compartment can store 1- 3 pallet (carton) units. At present, there are more users of beam-type racking structures than corbel-type ones. There is a trend of further increase. Currently, steel structures or steel-wood structures are used more often, but with the The development of lightweight plastic industry and injection molding technology. Plastic pallets (cartons) will play an important role in pallets (cartons) of smaller size and weight due to their appearance, corrosion resistance, and light weight.
< p> 2. Stacking craneThe stacker crane is the main execution equipment for storing and retrieving goods in the automated three-dimensional warehouse. It can carry the goods to move horizontally, lift and reach left and right in the aisle of the shelf. To complete various operation functions such as warehousing, unloading, and reversing, the horizontal, vertical, and reaching movements of the stacker are set at two or more speeds (or stepless adjustment with frequency conversion). speed). To reduce the impact when parking, and can be accurately positioned to meet the stopping accuracy requirements of ±10mm for horizontal operation, ±10mm for vertical lifting, and ±5mm for left and right reach. The stacker is equipped with a virtual and solid detection device for the cargo space and the loading platform. To prevent accidents caused by repeated warehousing when the cargo space is already occupied due to control (or management) errors, the stacker should set the original position and stop accurately. If the stacker does not stop accurately due to inertia or other reasons, the stacker will follow the instructions. PC; program control automatically "corrects deviations". In addition, the stacker is also equipped with terminal speed limits and limit switches for operation, start and end, and a mechanical stop is set at the final end to prevent the stacker's various mechanisms from operating beyond the limit position. In order to ensure For the safety of the driver and cargo of a stacker crane with a driver's cab, the cargo platform is equipped with a rope-breaking protection device or a speed-limiting anti-drop device. The electrical system of the stacker crane is also equipped with conventional electrical interlocks, voltage loss protection, zero-position protection, Overload protection and other functions The current operating speed of each mechanism of the stacker is: horizontal operation 80m/min: lifting 10-16m/min; fork 8-15m/min
3. Personnel outbound distribution system<. /p>
In the automatically controlled three-dimensional warehouse, the inbound and outbound distribution system allocates the incoming goods to a certain lane entrance according to the computer instructions, and then the lane stacker sends them to the designated row or column according to the instructions. , layer cargo position. Output in the opposite direction. A weighing device can be installed at the entrance of the goods. An over-height and over-width size detection device will prevent the goods entering the warehouse from being overloaded, overweight, or oversized.
At present, roller or chain conveyors are mostly used to transport goods according to the structure and weight of the goods, pallets or containers. Elevators are often used to solve the height difference problem at intersections where goods are transported. In addition, a conveying channel should be set up so that goods (pallets) with unqualified weight and size can be transported to a designated point for sorting before entering the warehouse area. It can also be used when picking in and out of the warehouse (parts entering and leaving the warehouse), sending unit goods there and returning after picking. When the frequency of entry and exit is not high, you can consider using one stacker crane for several lanes. At this time, a transfer car or other transfer equipment should be equipped. In order to transfer the stacker to another lane.
4. Automatic control system
All operable equipment in the warehouse area, such as stackers, conveyors, elevators, distribution cars, transfer cars, etc., as well as the operation guarantee system of these equipment, All should be controlled by a unified computer program. The control system has alarm and diagnostic display functions for mechanical, electrical and other faults. And you can handle some alarms by yourself. The operation of each equipment realizes automatic connection and the operation is reliable. Generally, a high-quality programmable controller (PC) is used. In order to ensure the smooth and reliable operation of each institution and accurate address recognition, high-quality frequency converters, photoelectric components and other high-quality control components should also be selected.
5. Computer management system
The computer management system should be able to complete the following main management functions for all cargo locations and all inventory goods:
(1) As required Realize management functions such as first-in-first-out, priority in certain lanes, and even distribution of goods, and manage inbound and outbound cargo locations;
(2) Inventory and query according to cargo locations and cargo types;
(3) Print various statistical reports;
(4) Inventory situation analysis;
(5) Modify the contents of the data file.
The management machine can use 486,586 microcomputers of various levels, and can realize online communication with subordinate monitoring and control machines. The communication method can use cables or closed safety slides, and it is best to use infrared signal transmission systems. Easy to install, reliable transmission and long life. As needed, digital, text or graphic analog display devices for equipment operation and operating targets can be set up in prominent locations in the warehouse area and in the machine room to monitor the entire operation process.
In summary, my country's three-dimensional warehouse industry has formed a certain scale and development capabilities. The current mainstream of the three-dimensional warehouse market is: single-machine automatic control, frequency conversion speed regulation operating mechanism (due to horizontal operation and cargo expansion and contraction cannot operate at the same time) . It can use the same frequency converter), a stacker with a closed sliding conductor power supply, a load capacity of less than 600 kg, and a height of 10-15 meters. It is equipped with cold-rolled thin-walled steel modular shelves, inbound and outbound conveyors or trolleys. A three-dimensional warehouse can be equipped with a management machine responsible for warehouse account management. But there is still a big gap compared with developed countries
Currently, the height of warehouses in developed countries such as the United States and Japan has reached tens of meters. The number of warehouses built reaches thousands. The running speed of the stacker exceeds 100m/min, and it has a variety of inbound and outbound logistics distribution systems and safety assurance systems. The forms of vertical storage equipment vary according to their uses. Gravity shelves have been successfully used, but they are basically blank in China.
3. Development is better than expected
1. Market development
According to incomplete statistics, by the end of 2006, the number of automated three-dimensional warehouses nationwide had More than 500 seats. In 2006, more than 80 automated three-dimensional warehouses were built, mainly in machinery manufacturing, automobiles, tobacco, food processing, clothing production, pharmaceutical production and circulation. Compared with 2005, the entire market has developed greatly. The main manifestations are:
(1) The number of automated three-dimensional warehouses constructed in the tobacco industry has declined, with about 10 new three-dimensional warehouses being built. Currently, the tobacco manufacturing industry still has some unfinished projects from the previous round of comprehensive technological transformation projects. Tobacco sales companies mostly use simple flat warehouses or forklift three-dimensional warehouses, and basically do not use automated three-dimensional warehouses.
If we hope that there will be a large market demand in the tobacco industry, we must wait for further upgrading and equipment upgrading of tobacco manufacturing and distribution enterprises;
(2) Pharmaceutical industry: Pharmaceutical production enterprises still have demand for automated three-dimensional warehouses Stable, 1,020 automated three-dimensional warehouses were built in 2006. Companies such as Sanjiu Pharmaceutical and Yangzijiang Pharmaceutical have built automated three-dimensional warehouses as their production scale has expanded. Driven by GSP certification, pharmaceutical distribution companies still have great demand for automated three-dimensional warehouses. In 2006, more than 10 automated three-dimensional warehouses were built;
(3) Some standard parts and fasteners in the machinery industry Parts manufacturing companies, valves, and water pump manufacturing companies have built automated three-dimensional warehouses;
(4) Although automobile manufacturers have adopted automated three-dimensional warehouses for the storage of car bodies and accessories, they basically use foreign products. Every year The number of new automated three-dimensional warehouses built in the automobile industry is between 10 and 20;
(5) Large dairy companies such as Yili and Mengniu are enthusiastic about building automated three-dimensional warehouses. In 2006, the industry built more than 15 automated three-dimensional warehouses. , and generally large scale, there are still many projects planned and constructed in 2007, including a certain number of refrigerated warehouses;
(6) Although the demand for automated three-dimensional warehouses in the home appliance manufacturing industry is still not strong, Home appliance sales companies such as Suning have built automated logistics and distribution centers, expanding the market for automated three-dimensional warehouses;
(7) In 2006, clothing industry giant Youngor took the lead in building an automated clothing logistics center, including 1 An automated three-dimensional warehouse. As the effects of use become more prominent and spread among enterprises, other enterprises will inevitably follow suit, and this industry breeds a huge market;
(8) The construction of automated three-dimensional warehouses in the military has accelerated, and the entire military has been included in the list in the past two years. There are dozens of automated three-dimensional warehouses planned to be built. Each supplier pays special attention to this market area, and competition will become increasingly fierce in the future.
2. Technology and product development
There is a certain demand in China for automated three-dimensional warehouses with working temperatures below 120°C for cold drink manufacturers, but currently domestic suppliers cannot provide them. Solutions and related products that fully meet the requirements are simply replaced with components suitable for low-temperature conditions, or some local heating and insulation measures are taken to barely meet user requirements. However, the effect is not ideal, and there is an urgent need for suppliers to conduct research on the overall design. We will start comprehensively in the research and development of equipment and provide overall solutions that suit the needs of the industry.
3. Supplier development
The overall number of companies in the industry has not changed much. Except for some companies that have failed to perform well and have faded out of the market, several foreign manufacturers have also joined the competition in the domestic market. At the same time, there have been The market demand in 2007 is promising as the phenomenon of foreign companies acquiring domestic companies has been eliminated.
The overall development of the automated three-dimensional warehouse market in 2006 was steady and rapid. Although overall profits declined, all manufacturers had full production orders and sales results were better than expected. It is expected that the situation will be better in 2007, and the construction scale of automated three-dimensional warehouses will be close to 100 throughout the year. In the future, as the scale and number of Chinese enterprises expands, and the awareness of attaching importance to and rationally using land as a scarce resource continues to increase, automated three-dimensional warehouses with the advantages of saving land resources and improving the level of enterprise management will surely be more widely used. The further expansion of application fields will put forward new and higher requirements for corresponding equipment and technology. Chinese enterprises must carry out comprehensive technological innovation and product upgrades in order to seize the opportunities given by the times.
4. Adapt to national conditions and develop appropriately
At present, our country has basically established a market economy. The development of technology is undoubtedly promoted or restricted by the market. However, because the market is not yet very complete and standardized, it often depends on more than just demand. Especially for larger projects such as three-dimensional libraries (ranging from hundreds of thousands to millions or more). Funding often becomes the key. However, with the development of all walks of life, my country's three-dimensional warehouse industry will also make great progress. In the next few years, there will be an increasing number of fully automated three-dimensional warehouses where management machines, stackers, and inbound and outbound distribution systems are networked together, becoming the mainstream of the three-dimensional warehouse market.
As the market expands, new types of three-dimensional warehouses with higher-level management and control systems will continue to appear. Designing and manufacturing special stackers and logistics transportation systems suitable for various goods will become one of the important tasks of three-dimensional warehouse manufacturers. one. Shelf production processes and shelf profile rolling processes that are lighter, have better assembly performance and better stability will also be developed and improved. In short, my country's automated warehouse technology will continue to update and develop with changes in the domestic market. At the same time, the professional experience of three-dimensional warehouse design and manufacturing units will also guide and promote the progress of my country's three-dimensional warehouse industry.
5. Introduce advanced technology and reach a new level
Judging from the current situation of three-dimensional warehouse design, manufacturing and use. Developed countries are ahead of us. It is undoubtedly a shortcut to introduce, digest and absorb advanced foreign products and technologies, and eventually localize them into our own products. The prerequisite is to introduce advanced projects that are suitable for the domestic market. Never introduce it blindly. At present, there are very few domestic companies that have introduced a complete set of technologies for the main equipment of the three-dimensional warehouse. In a sense, whoever takes the first step is left to chance. Who will be able to take the lead and occupy the market. The following points should be grasped when introducing:
(1) The comprehensive technology of advanced practical products should be introduced, that is, not only the products should be introduced, but also the design and process technology should be introduced. Novel designs are equally important as advanced process methods, and improvements in process technology are often more costly and laborious.
(2) Digest and absorb quickly. Master your own skills as soon as possible.
(3) Localize as soon as possible. You cannot rely on imported parts for a long time. But one principle must be grasped. That is, the quality of domestic replacement parts should not be lower than imported parts. Otherwise, the significance of introduction will be partially lost.
(4) When introducing technology, we must not only see the current market demand, but also see the future market development. After digestion and absorption, the product should be an advanced product in the current market. Establish a higher starting point and develop your own development capabilities on this basis. Stay ahead of the market changes. If the above points can be achieved, the introduction will be successful.