The Classification and Purpose of Gantry Crane
ZZHZ is a professional manufacturer of gantry crane, which is widely used in various of construction projects. With the characteristics of the reasonable design, convenient assembly and dismantling, high reliability and wide variety, the gantry crane made by ZZHZ can meet the different customers’ requirements and enjoy the good reputation in this field.
1, Classify as per the main girder type
(1), Single-girder gantry crane
The single-girder gantry crane with simple structure and light self-weight whose main girder structure usually adopt the box-girder structure, also it’s very convenient to assembly and dismantling. Compared with the double-girder gantry crane, its stiffness is much weaker. The supporting legs of single-girder gantry crane have two types: “L” and “C”. Regarding the “L”, whose production and installation is very convenient, structure stress is better, self-weight is lighter, however, the disadvantage is the lifting space between two legs is small. Regarding the “C”, the feet are made into sloping and curved type. The most advantage is the horizontal lifting space is large enough to guarantee the goods can move smoothly.
(2), Double-girder gantry crane
Double-girder gantry crane which has many features: large lifting capacity, span, high stability and variety, but its self weight is larger than the other ones and the total price is more expensive. Usually it has box girder and truss girder, generally speaking the box girder is more popular.
2, Classify as per frame structure
(1) Gantry crane
a, Full gantry crane, no cantilevers, the trolleys move along the main girder which length is just between two supporting legs.
b, Half gantry crane, the height of two supporting legs is decided by the construction site situation.
(2) Gantry crane with cantilever
a, Double cantilever gantry crane, it’s a common style which structure stress and land occupation is efficient and reasonable.
b, Single cantilever gantry crane which is selected by the limited construction area.
3, Classify as per the main girder structure
(1), Truss girder structure
It is a structure which needs to be welded by the angle steel or I-steel. Its advantage is low price, light self-weight and high wind-resistance. However because of the many welding points and self faults, the truss girder structure also owns the following disadvantages: large deflection, low stiffness and relatively reliability, the welding points needed to be checked frequently. It is applied for the occasions whose requirements are low and small lifting capacity.
(2), Box girder structure
It is a box-girder structure welded by the steel plate, with the characteristics of high safety and stiffness. Generally speaking, when the lifting capacity is large or super-large tonnage, we will introduce this style. For example: MG1200 gantry crane made by ZZHZ (Zhengzhou Huazhong Construction Machinery Co.,Ltd)
(3), Honeycomb girder structure
Usually it means the “ISOSCELES TRIANGLE” honeycomb-girder, the main girder is welded by honeycomb style steel plate and triangle web-steel.
Compared with the box girder structure, the center of gravity is low, self weight is light, the safety is high and the wind-resistance is better.
Compared with the truss girder structure, it has the characteristics of large welding contact, the structure stress is even, low deflection and high stiffness. Because it’s welded by the steel plate, the self weight and price will be higher than the truss structure. The honeycomb girder gantry crane is the patent product of ZZHZ (Zhengzhou Huazhong Construction Machinery Co.,Ltd).
4, Classify as per the purposes
(1), The general purpose gantry crane
This kind of gantry crane adopts the box girder structure and truss girder structure and has comprehensive purpose. It usually includes the hook, grab, electromagnetic and hoist also the half gantry crane.
(2), The hydropower station gantry crane
Generally speaking, it’s used to lift the water gate and the installation. This kind of gantry crane is barely used, however once put into use, the frequency will be constant. Therefore, we need to improve its working level.
(3), Ship-building gantry crane
It’s mainly used to assemble the ship body. Equipped with two trolleys, one with 2 hooks moves along the above swing of the rail. The other one with a main hoist and auxiliary hoist moves along the below swing of the rail to overturn and lift the ship-body parts.
(4), Container gantry crane
This kind of gantry crane is special for loading and unloading containers. It also is divided into type container gantry crane and rail-mounted container gantry crane.