Current situation and new technology of the hottes

The current situation and new technology of crawler cranes (1)

the turntable structure mainly has two factions, one is the closed turntable structure represented by Europe and the United States, and the other is the small box turntable structure represented by Japan. The closed structure is composed of two I-shaped or box shaped sections with large height. It has good rigidity and is widely used in large products. The small box structure is equipped with a support connection mechanism on the small box section, and a shed is set on both sides to place the engine, oil tank, rotary mechanism and other components. In order to facilitate maintenance, Japan has launched a new semi open turntable structure, with components placed on one side and a walking board set on the other side, which is completely open, so that the maintainer can easily access the mechanism and power components, replace vulnerable parts or check the operation condition. (5) When the instigation needle rotation stops, the unloading handle can be pushed back to remove the main experimental force

considering the convenience of transportation, the turntable shall be disassembled and transported for large tonnage cranes. There are two types of turntable assembly methods. One is that the turntable, slewing ring and a part of the frame are connected into a whole, and the other parts of the turntable can be transported independently or disassembled for transportation. For example, manitowa estimates that the transaction price of imported ore market may not be improved in a short time. The m21000 product of G company. The other is to transport the loading and unloading separately, and the separated part is connected with the slewing ring in a quick way, such as the quick pin shaft connection of the cc5800 product of Terex Demag company

the improvement of the structure of the lower carriage is more obvious. Considering the increase of walking traction capacity and working speed, the four-wheel drive type can be selected for the walking mechanism. The structure of the crawler frame is improved, and its tension is realized through the sleeve connection of the tensioning beam in the crawler frame structure. In order to reduce the driving torque, the driving wheel adopts the sprocket type to reduce the diameter, which is adopted by the CC2500 product of Terex Demag company. The number of crawler assemblies is also fundamentally changing. It is not only the traditional left and right crawler assemblies, but also multi group assemblies. For example, the 21000 product of manito and wacker company, the lower carriage is composed of 8 crawlers, each of which is a group. The load transmission principle is similar to the crane traveling structure of portal crane. Each crawler has more uniform load-bearing, lower requirements for the foundation, and can form wide and narrow modes to meet the requirements of different workplaces. The frame structure has also been significantly improved. Considering the convenience of transportation, the selection of higher priced materials for super large cranes will make their product cost too high. Generally, it is composed of three or more parts, the middle box structure (the upper end is connected with the slewing ring) and the box girders on both sides, The more novel structure is to improve the connection mode of the three, so that the longitudinal beam is placed radially, so as to reduce the concentrated load at the connection with the crawler frame