Which crane is best?
Telescopic Boom Advantages
Buildings, walls, whatever, with Unic wire-rope cranes you get precise high-lift placement and safe, sure operation. Their dependability is all in their strength and design, original Unic features.
Higher performance, too, at lower depths. Unic wire-rope cranes handle heavy loads in deep-hole jobs with accuracy and stability. A wide range of models assures versatile matching to job requirements.
Tight places are the right places for Unic wire-rope cranes. In any operating situation their strong steel cables mean extra dependability and safety. High, low or tight, Unic wire-rope cranes are always right.
An 8TM Unic easily lifts a 3 tonne cable drum. This is not possible even with a 9TM knuckle boom crane.
The lift curve graph of a typical 9TM knuckle boom crane (below) shows it cannot – in practice – lift a 3 tonne load onto the tray.
Knuckleboom cranes are very widely used in Australia.
Their typical application is delivery trucks i.e. loading/unloading work.
Effer knuckleboom cranes are also market leaders in cranes designed for earth auger and pole standing work.
Certain models are built with a heavy duty inner boom to absorb the stresses of auger work. With large capacity cranes (usually over 30TM) nothing matches the up and over reach ability of a hydraulic luffing (raise and lower) fly jib.
Fly jibs and big capacity cranes are an Effer specialty.
Caution – Lift Curve Grafts
Applies to Knuckleboom Cranes Only
All knuckle boom cranes with fixed hooks depend on their boom luffing (raising/lowering) cylinders to raise a load.
The angle of that cylinder to the boom greatly influences the leverage of the cylinder and– with that – the boom’s ability to lift the rated load.
Below is a typical 9 Tonne Metre Knuckle Boom lift curve chart. It shows you can lift 2,860kg at 3 metres. However, once the hook passes 2 metres above mounting level, the leverage drops away as does the crane’s ability to continue lifting that load any higher.
One solution is a linkage system between boom and column and the first and second boom.
Not every manufacturer offers this system or it may be available on certain models only.
Here are 2 near identical 17TM Effer cranes, one without twin link system and the second one with twin links.
Note the 175 with twin links will lift 5,050kg to 11 metres height of hook (1)
Whilst the 175 without the lever advantage can only place 3,160kg to the same height (2)
At reach, the 175 with links will place 1,255kg at 10 metre radius and 11 metre height of hook (3)
Whilst the non-link crane is 1,200kg at 8m radius for the same height (4)
So, Which Crane is Best?
Telescopic or Knucleboom..
It really does depend on the type of work you need to do. If this information has left you unsure, talk to us. We can certainly help with expert advice and working demonstrations.