The gantry crane can be classified according to the form of the door frame, according to the main beam form, according to the main beam structure, according to the use form.
Doorframe structure:It is divided into gantry crane and cantilever gantry crane
Portal crane
1. full door type crane: the main beam is not suspended, and the car is carried out in the main span.
2. half door type crane: the leg has high and low height, which can be determined according to the civil requirements of the site.
Cantilever gantry crane
1. double cantilever gantry crane: the most common form of structure, the force of its structure and the effective use of the site area are reasonable.
2. single cantilever gantry crane: this type of structure is often chosen because of the limitation of the site.
Main beam form:It is divided into single main beam and double main beam.
1. single main beam
Single girder gantry crane has the advantages of simple structure, convenient manufacture and installation, its quality is small, the partial rail box frame structure. Compared with the double girder gantry crane, the overall stiffness is weaker. Therefore, when the weight is Q = 50t, S = 35m span, can use this form. L type and C type two forms of single girder gantry crane legs. The manufacturing and installation of the L type is convenient, the force condition is good, and the quality of its own is small, but the space of the lifting goods through the leg is relatively small. The support of the C type is inclined or curved, with the aim of having large transverse space to make the goods pass through the foot smoothly.
2. double main beam
Double girder gantry crane span, strong bearing capacity, good overall stability, but its quality and varieties, the same as single girder gantry crane weight compared to the more high cost. According to the structure of the main beam, it can be divided into two forms, box girder and truss. Generally, the box structure is usually used.
Main beam structure:It is divided into trussed beam,box girder and honeycomb beam
1. trussed beam
The structure form of angle steel or I-steel welding has the advantages of low cost, light self weight and good wind resistance. However, due to the lack of welding points and the defects of the truss, the trussed beam also has the disadvantages of large deflection, small rigidity, low reliability and frequent detection of solder joints. It is suitable for a site with low safety requirements and less weight.
2. box girder
The use of welded steel box type structure, has the advantages of high safety, rigidity etc.. Generally used for large tonnage and ultra large tonnage gantry cranes. For example, the right figure MGhz1200, with a weight of 1200 tons, is the largest gantry crane in the country, and the girder adopts the box girder structure. The box girder also has the disadvantages of high cost, self important and poor wind resistance.
3. honeycomb beam
In general, it refers to "isosceles triangular beehive beams", the end of the main beam is triangular, and there are honeycomb holes on both sides of the oblique abdomen and the upper and lower chords. Honeycomb beams absorb the characteristics of truss beams and box beams, which have larger stiffness, smaller deflection and higher reliability than truss beams. But because of the use of steel plate welding, the weight and cost ratio of truss beam Shaogao. It is suitable for site or beam field that is used frequently or with large weight. Because the beam is a patented product, the manufacturer is less.
