Crane development trend

Material handling has become an important part of human production activities and it has been more than 5,000 years of development history. With the expansion of production scale and the improvement of automation, cranes, which are important equipment for material handling, are used more and more widely in modern production processes, and their functions are becoming greater and greater. The requirements for cranes are also increasing. The crane is undergoing a tremendous transformation.

Large-scale and specialization As the scale of industrial production continues to expand, production efficiency is increasing, and the proportion of material handling and transportation expenses in the production process is gradually increasing, which has led to a continuous increase in the demand for large-scale or high-speed cranes. As the lifting capacity increases, the working speed becomes higher and higher, and higher requirements are imposed on energy consumption and reliability. Cranes have become an important part of automated production processes. Cranes must not only be easy to operate, easy to maintain, but also have good safety and reliability, and must have excellent durability, trouble-free, maintainability and economical use. At present, the world's largest floating crane has a lifting capacity of 6,500 tons, the largest crawler crane has a lifting capacity of 3,000 tons, the largest bridge crane has a lifting capacity of 1,200 tons, and the maximum operating speed of a container-carried bridge crane has reached 350 meters. /min, The maximum operating speed of the stacker crane is 240m/min, and the hoisting speed of the crane for garbage treatment reaches 100m/min.

With the diversity of industrial production methods and user requirements, the market for special cranes has been continuously expanded and the varieties have been constantly updated, with unique functions to meet special needs and to achieve the best results. For example, special cranes for metallurgy, nuclear power, papermaking, and waste disposal, explosion-proof, anti-corrosion, and insulated cranes, as well as railways, ships, and container cranes, have increased their functions, and their performance has been continuously improved. The adaptability is stronger than ever. Germany Demag developed a special crane for aircraft maintenance and opened up the market in the international market. This kind of crane is installed on the structure of the house. It has a large span, high lifting height, can cross over, and has high parking accuracy. A multi-section telescoping duct is installed under the lifting trolley and is connected with the aircraft maintenance platform and can rotate 360 ​​degrees. Through the displacement of carts and trolleys, the lifting and rotation of the ducts, the maintenance platform can reach any part of the aircraft for maintenance and repair of the aircraft, which is extremely quick and convenient.

Modularization and Combining Modular design replaces the traditional design method of the complete machine. The components, parts and components with the same functions on the crane are used for multiple purposes, with the same connection elements and interchangeable standard modules. The mutual combination of modules forms different types and specifications of cranes. Improvements to the crane require only a few modules. To design a new type of crane, simply use different modules to recombine. The single-piece and small-batch production cranes can be replaced by modules with considerable batch production to achieve high-efficiency professional production. The company's production organization can also be changed from product management to module management. To improve the overall performance, reduce manufacturing costs, increase the degree of generalization, use fewer parts to form a variety of multi-species, multi-spec series of products, fully meet the needs of users.

At present, the famous crane companies in Germany, the United Kingdom, France, the United States, and Japan have all adopted the modular design of cranes and achieved significant benefits. After Demag's standard crane series was changed to a modular design, the design cost of the single-piece design was reduced by 12%, the production cost was reduced by 45%, and the economic benefits were considerable. German Demag also developed a KBK flexible combined suspension crane. The crane's steel structure is composed of cold-rolled rails. The crane's operation line can be arranged along the production process, and it can have crossways, turns, and spans. And change the gauge. All parts can be mass-produced, and then according to the user's different needs and specific material handling routes in a short time the various components with a mix of Serve. This kind of crane has very good combination, convenient operation, full use of space, and low operating cost. There are manual and automatic forms, but also can form suspension systems, single-girder suspension cranes, double-girder suspension cranes, cantilever cranes, light gantry cranes and manual stacker cranes, and can even form large-scale automated material handling systems.

Lightweight and diversified cranes with a large number of batches are used in general-purpose applications and the work is not very onerous. These cranes are bulky and have a wide range of uses. Considering the overall benefits, the cranes are required to reduce the height of the structure as far as possible, simplify the structure, reduce the weight and wheel pressure, and also reduce the height of the entire building, lighten the building structure, and reduce the cost. Therefore, electric hoist bridge cranes and girder cranes will have faster development, and will mostly replace medium and small tonnage general purpose bridge cranes. After decades of development and innovation, Demag Germany has formed a series of lightweight modular cranes. The lifting capacity is 1-63 tons and the working level is A1-A7. The whole series consists of I-shaped and box-type single beams, suspension box-shaped single beams, corner box-shaped single beams and box-shaped double beams. There are several types of layouts for connecting the main beam to the end beam and the lifting trolley, which can be adapted to the requirements of different buildings and different lifting heights. According to the user's needs, each type of crane has three kinds of single speed and three kinds of double speed for arbitrary choice, and also can choose variable frequency speed regulation. Manipulation methods include the ground flashlight door self-moving, the flashlight door moves with the trolley, the flashlight door is fixed, the wireless remote control, the driver's cab is fixed, the cab moves with the trolley, and the cab moves by itself. The Power Supply of carts and trolleys is based on two methods: conductive cable car and DVS system. With so many options, different combinations can be used with hundreds of cranes to fully meet the different needs of users. The other major advantage of this type of crane is its light weight, light weight, low wheel pressure, and small overall dimensions, which can significantly reduce the cost of building a building and can also reduce the crane's operating power and operating costs. Compared with general-purpose products, the lifting capacity is 10t, the span is 22.5m, the weight of the universal double-girder bridge crane is 24t, the height of the crane's rail surface is 1876mm, the crane's width is 5980mm; the weight of Demag's crane is only 8.7t, and the weight is 176 %, the height above the rail surface of the crane is 920mm, a decrease of 104%, the width of the crane is 2980mm, and the overall size is reduced by 100%.

The automation and intelligent cranes are renewed and developed, depending to a large extent on improvements in electric drive and control. Combining mechanical and electronic technologies, advanced computer technologies, microelectronics, power electronics, fiber optics, hydraulics, and fuzzy control technologies are applied to the drive and control systems of the machinery to realize the automation and intelligence of the cranes. The new generation of electrical control devices for large-scale and high-efficiency cranes has developed into a fully electronic digital control system. It is mainly composed of all-digital control drive devices, programmable logic controllers, fault diagnosis and data management systems, and digital control given detection devices. Variable frequency speed control, RF data communication, fault self-diagnosis monitoring, fuzzy control of spreader anti-sway, laser search center of gravity, near field sensor anti-collision technology, field bus, carrier communication and control, contactless power supply and 3D barcode Technology will be widely used. Make the crane more flexible, suitable for flexible production mode with multiple batches and less batches, and improve the comprehensive automation level of single machine. Focus on the development of high-performance electric actuators with microprocessors as the core, which enables the cranes to have excellent speed and static characteristics, automatic control of operations, automatic display and recording, automatic protection and automatic detection of crane operations, and special occasions. Remote control, etc. to meet the needs of automated production.

For example, a laser device is used to find the position of the center of gravity of the lifting object, and an ultrasonic sensor is arranged on the device to guide the device to automatically grab the goods. The automatic anti-sway system of the spreader can quickly reduce the swinging amplitude of the lifting object to several millimeters at a running speed of 200 m/min and an acceleration of 0.5 m2/s. Cranes can achieve high-precision positioning by magnetic field transducers or lasers. A near-field induction system is installed on the crane to avoid collisions between the cranes. The crane is also equipped with a microcomputer self-diagnosis monitoring system, which can provide most of the routine maintenance check content, such as the gear box oil temperature, oil level, wheel bearing temperature, crane load, stress and vibration conditions, brake lining life And temperature conditions.

The complete and systemized system is based on the crane's single machine automation. It uses a computer to form a material handling integrated system of various lifting and transporting machines. Through the control of the central control room, it is organically combined with the production equipment and coordinated with the production system. This kind of crane has a high degree of automation and has information processing functions. It can store, calculate, logically judge, and transform processing of various kinds of information detected by sensors, and then send out control instructions to the executing agencies. These cranes also have good information input and output interfaces to achieve full, accurate and reliable information transmission throughout the entire material handling integrated system. Through the system integration, the crane can form the best match and combination of different models, complement each other and achieve the best effect. Currently focused on the development of a factory production and transportation automation systems, flexible processing and manufacturing systems, commercial distribution and distribution system for commercial goods, container handling and handling systems, transportation and postal and telecommunications departments for automatic sorting and handling of goods and packages.

For example, Caterpillar's Metal Structure Factory in the United States of America used for production and construction machinery purchased an automatic material handling system mainly for bridge cranes, which was used for steel blasting, cutting, and warehouse loading and unloading operations. Operating efficiency increased by 65%. The Toshiba, Kawasaki, Japan facility uses a material handling system consisting of a fully automated bridge crane to move the fixtures and workpieces on the flexible processing line to deliver blanks to the machine tool or to send the machined parts to the next process or warehouse. These space-moving crane handling systems replace the automatic guided vans that were conventionally used in the past to make full use of the floor area of ​​the workshop.

The new structure and practical structure adopt thin-walled profiles and special-shaped steels to reduce the structure of the welded joints and improve the anti-fatigue performance. A variety of high-strength and low-alloy steel materials are used to improve the bearing capacity, improve the stress conditions, reduce the weight, and increase the appearance. Most bridge cranes adopt box-type four-beam structure. The main beam and end beam are connected by high-strength bolts, which is convenient for transportation and installation.

Further develop new types of transmission components in the organization and simplify the organization. The "triple play" operating agency is the mainstream of the light and intermediate crane operating agencies in the world today. It integrates motors, speed reducers and brakes. It has a compact structure, light and beautiful appearance, easy disassembly and assembly, simple adjustment, smooth operation, and a large range of support. Such advantages have been widely applied abroad to various crane operating agencies. In order to simplify the structure of the lifting trolley for small to medium-sized tonnages and reduce the height of the crane and reduce the wheel pressure, electric hoists have been widely used as lifting mechanisms in foreign countries. In order to reduce the weight, improve the bearing capacity, improve the processing and manufacturing conditions, increase the product yield, parts and components as much as possible to use welding for casting, such as reducer housing, scrolls, pulleys, etc. are welded structure. Reducer gears are hardened to reduce weight, reduce bulk, increase load capacity, and increase service life. The application range of hydraulic push rod disc brakes is also increasing. In addition, the motors used by all agencies are developing at high rotational speeds, thereby reducing the number of motor bases, reducing the weight and reducing the external dimensions, and can also apply brakes with low braking torque.

In the field of electronic control, we have developed a speed control system and an electronic control system with good performance, low cost, and high reliability, and developed semi-automatic and fully automatic controls. The use of electromechanical instrumentation fluid integration technology improves the performance and reliability of use and increases the functionality of the crane. In the future, it will pay more attention to the safety of cranes and develop new safety protection devices. Pay attention to the driver's working conditions, apply ergonomics to design the driver's room, and reduce the driver's labor intensity. In recent years, in order to solve the anti-sway control of crane hooks, Germany has developed a fuzzy logic circuit control technology, using neural information and fuzzy technology to find the best time to start acceleration, and the data input system for experienced drivers to prevent the actual operation of the pendulum. best control. The fuzzy control method can determine the control instructions for the implementation of automatic work, and subject the subjective fuzzy quantity to digital quantification through the fuzzy set, and then use the computer.

High Bay LED Lamps

High Bay LED Lamp,High Bay LED Lights,High Bay LED Light Bulb

In Home Lighting Co., Ltd , http://www.dg-ledlight.com