The other type of common truck mounted crane shown above in pictures 1 and 3 is the articulating crane or often called a knuckle boom or cargo crane. They call it a knuckle crane because of the pivot knuckle which allows it to fold up to a compact size when not in use. This crane is extremely flexible and because of its unique design can lift large capacities with ease and super maneuverability. They are also lighter than the telescopic cranes (the knuckle boom or articulating crane can also telescope), and this allows for greater cargo capacity on the truck and greater space on the truck because it folds up to a small space relative to the other style crane. This type of crane operates much like your finger does.
The articulating crane as shown in the first picture here is often mounted behind the cab and forward of the body. It is common to call these knuckle boom cranes. This particular one is designed to lift very large weights as the heavy steel dump body next to it on the ground. In picture number 3, this is commonly referred to as an articulating crane and you can see how tightly it folds up so that it takes up very little space. These are used on ships a lot for that same reason. But, don't let the folded up size fool you, these are serious cranes and can do the job. There is also a great deal of flexibility in where on the bed the crane can be located which can really help in certain applications.
West Coast Truck Equipment in West Sacramento has a great selection of high quality cranes for every need from the 700 lb Spitzlift crane to a 11,000 lb capacity cranes or more. Give us a call at 916-376-0690 for more information.
