
Single girder overhead crane
LD type electric single-beam bridge crane is installed on the crane girder with a solid electric hoist as a truck lifting mechanism. This product is ground operated.
The product is simple in structure, light in weight and cheap in price. It is mainly used for general hoisting and unloading operations in machinery manufacturing workshops, warehouses, assembly and maintenance of hydropower stations. The industrial ambient temperature of this product is -25 ~ 40℃. It is not suitable for the medium with explosion risk and fire risk, where the relative temperature is greater than 85% and the place is full of corrosive gas, and it is not suitable for the hoisting and transportation of molten metal and toxic, inflammable and explosive articles.
Structural characteristics and working principle
This series of products is composed of four main parts: bridge frame, lifting mechanism, car running, truck running and electrical. Wire rope electric hoist of trolley type is used as lifting mechanism. Crane assembly test shall comply with the provisions of GB/ t3695-1994. When installing the crane, it must be installed according to the provisions of the attached drawings.
When the crane is disassembled and transported and the product is installed, the connection of the end beam must be disassembled according to the drawing.
(1) main girder
This series adopts three-beam structure. The main beam and the end beam are connected by high-strength bolts. In order to prevent the operating mechanism from driving to the limit position, buffer blocks are set on the left and right sides of the main beam.
(2) hoisting mechanism
The electric hoist adopted by the lifting mechanism is the electric hoist jointly designed and produced by professional manufacturers.
(3) carts
The vehicle operating mechanism adopts four-wheel drive, the driving motor is 2 sets of conical braking motors, and the number of driving wheels is half of the total number of wheels.
(4) electrical system
1. An overview
The operation of each mechanism of the crane is operated by the ground control button box. Ground control button box with electricity
With the coordination of the control equipment, the motor of each mechanism can start, change direction, lift and brake. The electric control system guarantees the cart
The ground control button box operated by the operating mechanism, whether reversing or lifting, can make the running motor smooth
Start and brake. When the local control button box changes from the operation to the lifting (the lifting to the lifting), the operation should be stopped first. Thus, the operation performance and operation index of the crane are improved, the starting times of the electrical equipment are reduced, and the electrical life and reliability of the crane are improved.
2. Operating conditions
The voltage of the main circuit and control circuit of the ground operated crane electrical system is 220V~ 380V, frequency 50HZ.
Working conditions of electronic control equipment:
(1) below 2000 meters above sea level;
(2) ambient air temperature is not higher than +40℃, not lower than -25℃;
(3) power grid fluctuation is ±10%;
(4) the relative humidity shall not exceed 85%;
(5) there are rain, snow and no water vapor occasions.
If the actual conditions of use are not in accordance with the above, please specify when ordering.
3. Electrical equipment
The operation of each crane mechanism is controlled by the ground control button box.
(2) the crane adopts centralized control mode, which is used for overload protection, loss of voltage, zero position, safety and limit protection of each mechanism of the ac motor on the crane. It works with the master command controller to control the operation of the motor of each mechanism, and also provides power, control and power supply for the lighting circuit. There are total contactor, fuse, ac contactor, time relay and so on.
(3) limit and safety switch
Limit switches are installed in crane operation, trolley operation and lifting mechanism to block the travel of each mechanism. When the limit switch is disconnected, the corresponding circuit is cut off and the mechanism stops. When the power is switched on twice, the mechanism can only operate in the opposite direction, thus ensuring safety.