A mobile crane is “a cable-controlled crane mounted on crawlers or rubber-tired carriers” or “a hydraulic-powered crane with a telescoping boom mounted on truck-type carriers or as self-propelled models.” They are designed to easily transport to a site for use with different types of load and cargo with little or no setup or assembly.
The Early Designs
The first ever design of the modern-day mobile crane was first used in Paris, France in the late 1860’s by the Appleby brothers. The first models were steam powered and designed to assist in the construction of various parts of Paris due to its incredible small roads and tight spaces which there where to operate. Today mobiles are still the preferred method of lifting for any medium to low rise buildings. They are far more economical and efficient in terms of durability. It is able to rig up and work in a matter of hours, and also change positions as needed during the course of a day.
How They Work
We use mobile cranes on a daily basis. They assist us in the erection of tower cranes and help to unload materials as they are delivered if the tower crane is busy or is not ready for the materials at that very moment. They will perform lifts from a stagnant position, but they also have the ability to pick up a load and carry it in front as they drive their way into position.
Choosing a Mobile Crane
Like tower cranes, mobile cranes come in a variety of sizes—anywhere from 5 ton machines right up to 1000 ton plus machines. However, when choosing your mobile crane you must still consider the same process as if you were choosing a tower crane. For example: how tall is the building, how much weight am I lifting, and how far is the radius from which the mobile is positioned.
Mobile Crane Safety
You must always remember that a mobile crane does not hover over a building it works from the ground up. Therefore you must ensure that the boom of your mobile is able to extend that high in the air as to reach far enough to your required destination while at the same time staying within the weight guidelines set forth by the manufacturer for that radius. If you do not adhere to the guidelines then you will experience a mechanical failure and this comes with severe consequences.
When you are working with a mobile crane from a stagnant position ensure that all your outriggers are extended to the full width. Because all of the load will be transferred back to these riggers it is vital that before any lifts are performed you have taken careful consideration that the ground underneath the riggers is capable of sustaining this weight. A good trick is to place square, steel mats under each outrigger. The bigger the mats the more the weight gets dispersed and there will not be as much of a Kn/m2 loading imposed. This is particularly important when working on city streets or close to river banks or edges of compacted earth.
If you have further questions or need helping sourcing a mobile crane please contact us today.