Container crane

The rail mounted container gantry crane is composed of main beam, rigid and flexible gate legs, running trolley, lifting mechanism, crane running mechanism, electrical system, operating cab, etc. According to the operation process of the storage yard, the cantilever in the direction of single door leg or double door leg becomes the single cantilever or double cantilever model, and the non cantilever model becomes the non cantilever model. Different structural forms of cantilever free, single cantilever and double cantilever are determined according to the site, container storage and transportation process and loading and unloading vehicles (container trucks or railway vehicles).

The rail type container gantry crane is divided into different forms according to the structure of main beam and gate leg and the anti rolling device adopted.

(1) Double cantilever rail container gantry crane because the container needs to pass through the space in the legs on both sides. Therefore, the clearance in the width direction of the door leg is large. According to the different forms of the main beam carried by the gate leg, the double cantilever rail container gantry crane generally adopts the upper part of the gate leg to be opened into a "U" shape and connected with the upper part of the gate leg“ Π” Shape. The structure of non cantilever rail container gantry crane is relatively simple because the container does not have to pass through the space in the door leg.

(2) Compared with the quayside container crane, the trolley running speed of the rail mounted container gantry crane is low, and generally there is no anti rolling device. If the user requests to reduce the operation intensity and improve the productivity, the anti rolling device is set. For rope type lifting mechanism, its anti rolling is generally achieved by applying damping to the rope; For the rigid lifting mechanism, its anti rolling is achieved through rigid components.

Rail mounted container gantry crane

Rail mounted container gantry crane is mainly used for container loading, unloading, handling and stacking in container railway transfer yard and large container storage and transportation yard.

The rail mounted container gantry crane is composed of main beam, rigid and flexible gate legs, running trolley, lifting mechanism, crane running mechanism, electrical system, operating cab, etc. According to the operation process of the storage yard, the cantilever in the direction of single door leg or double door leg becomes the single cantilever or double cantilever model, and the non cantilever model becomes the non cantilever model. Different structural forms of cantilever free, single cantilever and double cantilever are determined according to the site, container storage and transportation process and loading and unloading vehicles (container trucks or railway vehicles).

The rail type container gantry crane is divided into different forms according to the structure of main beam and gate leg and the anti rolling device adopted.

(1) Double cantilever rail container gantry crane because the container needs to pass through the space in the legs on both sides. Therefore, the clearance in the width direction of the door leg is large. According to the different forms of the main beam carried by the gate leg, the double cantilever rail container gantry crane generally adopts the upper part of the gate leg to be opened into a "U" shape and connected with the upper part of the gate leg“ Π” Shape. The structure of non cantilever rail container gantry crane is relatively simple because the container does not have to pass through the space in the door leg.

(2) Compared with the quayside container crane, the trolley running speed of the rail mounted container gantry crane is low, and generally there is no anti rolling device. If the user requests to reduce the operation intensity and improve the productivity, the anti rolling device is set. For rope type lifting mechanism, its anti rolling is generally achieved by applying damping to the rope; For the rigid lifting mechanism, its anti rolling is achieved through rigid components.

characteristic

Rail mounted container gantry crane mainly has the following characteristics:

① The lifting speed is low and the crane running speed is high. According to the requirements of the container yard, the lifting height of the rail type container gantry crane is determined by stacking three times four or stacking four times five. Because the lifting height is not high, the lifting speed is correspondingly low. However, the length of the container yard is generally long along the running track direction. In order to achieve a certain productivity, the crane runs at a higher speed.

② The running speed of the trolley can be determined according to the span of the bridge and the extension distance at both ends. When the span and cantilever length are small, the trolley running speed and productivity requirements can be relatively small. When the span is large and the cantilever length is large, the running speed of the trolley can be increased correspondingly to meet the productivity requirements.

③ When the span exceeds 40m, during the high-speed operation of the crane, the deviation will occur due to the different running resistance of the door legs on both sides. Therefore, a synchronization device is set to keep the running speed of the running mechanisms on both sides synchronized through the electrical control system.

④ In order to meet higher requirements, the electric drive control system adopts thyristor DC or AC speed regulation drive control system to achieve better speed regulation and control performance. The electrical control system can also adopt conventional AC eddy current speed regulation control or AC stator voltage regulation speed regulation drive control system. For the electrical control system of the crane operating mechanism with high speed, the thyristor DC and AC speed regulation control system or AC stator voltage regulation and speed regulation control system with electrical braking is usually used, and the way of braking by the brake during operation and parking in the conventional electrical drive system is avoided, so as to avoid great impact on the whole machine. [1] 

Metal structure:

The steel structure of rail mounted container gantry crane generally adopts box structure. In order to reduce the weight of the whole machine, truss structure can also be used, but the manufacturing cost is high.

The structure of the whole machine is widely used depending on the support mode of the door leg“ Π” Type and "U" type“ Π” Both rigid and flexible door legs are“ Π” Form, the transverse stiffness of the two main beams and the strength and stiffness of the gate leg itself are realized by the stiffness of the gate leg and the beam on the gate leg. The "U" structure door leg is realized by the connection stiffness between the door leg and the lower beam of the door leg.

(1) Main beam structure. The main beam structure is composed of two box end beams, and the frame beam is supported on rigid and flexible legs. At present, eccentric box girders are often used. In order to avoid the high stress zone caused by wheel pressure, the rail bearing part adopts "t" steel to weld with the main beam panel and bearing web. The connection between the main beam and the rigid leg adopts high-strength bolts or welding, and the connection with the flexible leg adopts hinged connection. For the convenience of installation, the connection between the main beam and the end beam generally adopts high-strength bolts.

(2) Door leg structure. Both rigid and flexible portal legs adopt box structure. For the rail type container gantry crane with medium and small span, the portal legs on both sides are made into rigid portal legs. Right“ Π” For U-shaped door legs, the strength and stiffness along the crane direction are achieved through the rigid connection between the door legs and the top beam: for "U" shaped door legs, the strength and stiffness along the trolley direction are achieved through the rigid connection between the door legs and the bottom beam, while the strength and stiffness along the trolley direction are achieved through the rigid connection between the main beam and the rigid door legs. For the rail type container gantry crane with medium and small span, the deflection force on the portal legs and main beam caused by the unsynchronism of the cranes on both sides is borne by the rigid and single degree of freedom articulated connection of the main beam with the rigid legs and flexible legs.