Beam crane: details and specifications

In all spheres of human activity, a beam crane can be used to move heavy loads. It is a load-gripping mechanism, placed on a telpher (freight trolley), which moves along a beam bridge. This type of special equipment is one of the most common. At the beginning of the 21st century, in the territory of the former Soviet Union, according to various sources, from 1 to 1.5 thousand copies were produced annually at 17 specialized plants.

General device

In general, the design of a beam crane consists of span beams, often referred to as a bridge, and also from end supports. Beams and supports are made in the form of a rectangular prism. Inside them, for a uniform distribution of stresses and ensuring the stability of vertical walls, there is a diaphragm - steel plates diagonally welded to internal surfaces. The girder crane has an upper and lower belt. On the upper belt there is a rail track, on which the span beams are supported. There are also abutments that restrict horizontal movements. On the side faces of the beams there are small areas with rails for maintenance of the crane. A freight trolley is mounted on the passing beam. For the movement of the structure is responsible for a special drive, made by various schemes.

Drive and telpher of the girder

The movement mechanism of the crane is an electric drive with cylindrical or conical support wheels. Cylindrical wheels are used when the cargo is transported only in a straight line. The tapered supports center the girder on the rails and are used if the tracks have curved sections. The electric drive can be made according to various design schemes. The cargo trolley is a frame structure that rests on the running wheels of the passing beams. It has a mechanism for lifting cargo - electric or manual, and also provides a stop limiter hook. In low-tonnage cranes, electric hoists are used as a freight trolley , which are rigidly fastened to the frame of the trolley.

Types of girder cranes

Depending on the design features, the beam cranes can be supporting, hanging and gantry cranes. The first type is a construction mounted on an elevated track - the vertical racks act as supports, on which rail threads are installed. As a rule, the support girder crane is used in open space for transportation of bulky and heavy loads. Suspended cranes are used in enclosed spaces and are installed on beams specified in the construction of the building. Their main advantage is the small size in height, as well as the possibility of mounting in separate sections of the shop. Their rail track can have a curvilinear outline.

Gantry structures are used exclusively for transportation of multi-ton cargo. They are a structure of vertical supports (capable of moving in a horizontal plane) and horizontal beams. The scope of their application - loading and unloading and construction and installation works.

Tower cranes with beam arrow

A special place on the construction site is a tower crane with a beam arrow. It is a common design for performing loading, unloading, assembly and construction work at various sites. The boom of this crane is a truss, triangular, rectangular or square shape.

In the arrow, the upper and lower belt are highlighted. On the lower edge of the truss, the freight trolley is moved by an electric drive. In some cases, it can be rigidly fastened to the beam itself. In this case, the movement of loads in the horizontal plane occurs due to the movement of the arrow itself along the guides.

The beam can be located strictly horizontally or at an angle of 30-45 °. The crane with a beam arrow has a number of advantages. Firstly, this is the rapid movement of goods in the horizontal direction. Secondly, this is a large radius of coverage of the territory. And finally, the absence of blind zones - the crane can reach the cargo even in the immediate vicinity of the support.

Characteristics of girder cranes

Depending on the load capacity, the girder crane can be assigned to the first (up to 5 tons), the second (up to 50 tons) or the third (up to 320 tons) group. As a lifting mechanism, a winch with an electric drive is used. If the girder crane has enough load capacity characteristics, then it is equipped with two lifting mechanisms: the main and additional. The other important characteristic of a beam crane is the width of the span. The larger it is, the more massive the structure will be, which is due to the magnitude of the bending moment and stresses occurring in the middle of the span. There are multi-span structures that are installed in wide spaces. They lean against several beams at once - along the edges and in the middle.

Beam control system

Crane control is most often ground-based. An analogue console, located in the immediate vicinity of the operator, is connected by wires to the lifting and transporting mechanisms. Another common method of control is remote. Details of the girder crane obey the computer, which, in turn, is controlled by the operator. Cranes with control from the cabin are used in large industrial facilities. The driver, who is in the cab, directs the entire transportation process. Such a crane is equipped with an alarm system for signaling slingers, as well as a special landing pad.