Introduction of several common harbor crane
There are many types of harbor crane, such as overhead traveling crane, jib crane, gantry crane, etc.Gantry crane is developed with the development of port, its hoisting mechanism, wheel mechanism and bridge structure are as same as the bridge crane. Due to the large span, crane operation mechanism mostly adopts driving method respectively, in order to prevent the crane titling operation or increases the resistance, even the accident. The hoisting trolley frame of gantry crane runs on the bridge, there are some trolley is just a type jib crane.
What is a bridge crane?
The legs on both sides of the bridge crane are generally rigid legs. When the span is more than 30 meters, only one side adopts rigid leg, the other one is a flexible leg connected with the crane span structure through the ball joint. The gantry frame is designed as a statically determinate system, so that the crane can avoid the additional stress caused by lateral thrust, because of the under external loads, also be compensated the temperature of the bridge longitudinal deformation because of the big wind area of gantry crane , in order to prevent falling or tipping row in strong wind. With anemometer and is equipped with the operation of interlocking crane rail device. There can be no jib on both ends of the bridge, can be one at only one end or can be one at each of the end, in order to expand the operation range. As for the bridge of semi gantry crane, there is a leg on one of the ends and the other end without, it run directly in the tower of the rack.
Truck crane is a economic crane for large liquidity occasion
Truck crane is on a general purpose or special truck chassis equipped with lifting device and equipment of the crane. It has the advantages of good performance, flexible and large speed. Therefore, truck crane is especially suitable for large liquidity, and no fixed operation place. Due to it adapts on the ready-made chassis, its manufacture is very easy and economic. Because of the many properties of truck crane, with the rapid development of automobile industry in recent years, the varieties of truck crane production have very large development. But the truck crane also has its disadvantages, for example, the truck crane frame is longer and turning radius is big (because of the limit of automobile chassis).
Tyre crane is a special designed lifting equipment
The tyre crane is also a kind of lifting equipment, equipped with moving tire chassis, which is specially designed for it. Because of its chassis is designed specifically, the axles, wheel track and boundary dimensions are decorated reasonably according to the overall design requirements. In recent years, with the rapid development of crane technology, the crane tonnage is become more and more large, its speed is faster and faster, the distance between them are gradually reducing.
Crawler crane has a more excellent performance
Crawler crane is a lifting device based on a caterpillar chassis, by walking return roller in its closed driving rolling on the crawler crane. Compared with the tyre crane, the average pressure on the surface of crawler crane is small. It can work on the soft, mud or bad ground, in addition to this, the ability of the climbing and traction performance is excellent, it can drive with the load, and realize multi-usage with the aid of additional devices. So large crawler cranes, whose lifting weight is greater than 100 t, occupy an important position in the bridge construction. At present, the largest lifting weight of crawler crane can up to 3000 t. But its own weight is large, the speed is very low and the road will be destroyed during the crane operation. Thus the light crawler crane(blew 100t)has being gradually replaced by hydraulic truck crane.
