Crane drive and its structure (1)

 Can be divided into two categories: one for the central drive, which uses an electric motor to drive long shaft-driven initiatives on both sides of the wheel; another is separately driven, that is active on both sides of each wheel driven by an electric motor. Medium and small  bridge gantry crane  more use brakes, gear units and motors combined into one "triple play" drive mode, a large common bridge crane lifting weight for ease of installation and adjustment, universal coupling drive device often used . Structural crane (crane) run institutions generally only four driving and driven wheels, if from the weight of a large, common approaches to reduce the wheel increases wheel pressure. When more than four wheels, a frame must be balanced hinge device, the steel crane  load is evenly distributed on each wheel.

The metal structure of the bridge from the main beam and side beams, divided into single girder and double girder bridge bridge categories. Single girder bridge by a single span girders and located on both sides of the end beam composed of two dual-beam bridge girders and by the end beam components.

Main beam and side beams rigidly connected to the wheels at both ends with end beam for supporting the run on the elevated bridge. Main beam welded rails for lifting trolley. Bridge girder structure type more typical of a box-shaped structure, four truss structure and fasting truss structure.

Box-shaped structure can be divided into track box-shaped double girder, double girder rail box migraine, migraine rail box single girder and other types. Track box-shaped double beam is widely used in a basic form, the main beam from the upper and lower flange plates and sides of the vertical web composition, trolley rails arranged on the flange plate on the center line, and its simple structure, ease of manufacture, suitable for mass production, but the larger self.

Partial rail box double side rail box girder and single girder cross-section are from the upper and lower flange plates of different thickness and composition of the main and sub webs,sino hoist trolley rails arranged in the main webs above the cabinets short stiffening board omitted, in which one side rail box girder by a wide flange box girder instead of two main beams, weight smaller, but more complex manufacturing. Four truss structure consists of four combined into a closed space plane truss structure, the upper surface of the horizontal truss generally paved walkway plates, light weight, stiffness, but compared with other structures, size large, more complex manufacturing, fatigue low intensity has been less production.

Fasting truss structure similar off-track box girder by four steel plates form a closed structure, in addition to the primary web is a real belly-shaped beam, the other three steel plates in accordance with the design requirements into many windows, forming a non-helical rod fasting truss, the upper and lower horizontal truss paved walking platen surface, cranes operating agencies and electrical equipment installed in the tray inside, lighter weight, the overall stiffness, which is more widely used in China as a pattern.