The Main Technical Parameters Of Mobile Cranes
A mobile crane is a type of rotating boom crane. It is driven by its own power system and is also called a self-propelled crane. A tire crane is a kind of mobile crane, which adopts a specially designed tire chassis, has a large wheelbase, good stability, and can work in four directions, front, back, left and right. It can lift loads without outriggers on flat ground.
The main technical parameters of the mobile crane are:
1. Lifting capacity
Lifting capacity is the mass of the item that the crane can safely lift, in t. For mobile cranes, the rated value varies with the amplitude. The lifting capacity marked on the nameplate refers to the maximum value of the lifting capacity of the basic boom at the minimum amplitude.
2. Amplitude L
Amplitude is the horizontal distance between the vertical centerline of the hook and the centerline of rotation when the hook is on a horizontal field, in m. It is a function of the boom length and the boom angle. When the wall frame length is fixed, the larger the angle, the smaller the amplitude.
When working laterally with outriggers, the horizontal distance from the vertical centerline of the hook to the centerline of the outrigger on that side is called the effective amplitude.
3. Lifting height
Lifting height is the vertical distance from the center of the hook to the ground when the hook is lifted to the highest limit position, in m. When the boom length is fixed, the lifting height will increase as the amplitude decreases.
4. Working speed V
(1) Lifting speed. It is the vertical displacement speed of the rated load lifted by the lifting mechanism in a stable running state, in m/min. In order to reduce the power and impact force, the mobile crane should adopt a lower lifting speed.
(2) Amplitude changing speed. It is the average horizontal displacement speed of the amplitude changing mechanism in a stable motion state, in the amplitude changing plane, with the minimum rated load, from the maximum amplitude to the minimum amplitude, in m/min. Sometimes it is expressed by the time from the maximum amplitude to the minimum amplitude. The amplitude changing speed has a great influence on the stability and safety of the lifting operation, and the average speed is about 15m/min. (3) Rotation speed ω.
It is the rotational angular speed of the rotating mechanism in a stable motion state, driving the rotating part of the crane, in r/min. Limited by the rotational start-stop inertia force, the rotational speed cannot be too large, usually about 3r/min, and the rotational speed decreases accordingly when the rotational radius increases.
(4) Walking speed v.
It is the running speed of the mobile crane in a stable state on the road, in the unit of the transfer speed of the working place should be fast, the car crane has a relatively high walking speed, can form a team with the car, the tire crane has a lower walking speed than the car crane.