Specification :
Our CJ series tower cranes have the following features:
1.A 6 meter ( 19.7 ft.) , folding Cross Base is transportable in a single bundle on standard transport, complete with height adjustable screw-jacks and steel support cones. On arrival, the base is simply unfolded, placed onto the prepared ground and fine leveled with the screw jacks provided in each corner in a matter of minutes.
2.Thanks to the interchangeable, bolt-on feet system of COMANSA JIE, this base can be used with all COMANSA JIE mast sections, allowing free-standing heights up to 65, 50 meters ( 215ft.) for the 21CJ Series
3.The mast sections used in the CJ21 Series are from the well-tried modular, pin-jointed system, so successfully used by COMANSA JIE on the CJ21series cranes. COMANSA JIE mast panels are manufactured to tolerances that permit the weight of the crane to rest on the corner angles of the mast, rather than on the pins. This ensures long-life in addition to fast and safe installation.
4.Faster erection with 5.5m height of mast sections
5.Easily dismantled into panels for long-distance transport, a large number of mast sections can be transported in one container, considerably reducing transport costs.
6.Higher Free-standing Height
Joint mast sections with different transition sections , we can get much higher free-standing height .
7.With the elimination of the â traditionalâ cat-head and pendant lines the CJ series Flat-Tops have many important advantages, which have undoubtedly made this crane a most interesting alternative for a fast-growing number of users and rental companies:
à Fast, simple and safe erection of small, light individual modules.
à Components can be erected directly from truck to crane.
à Smaller mobile crane required for lifting light components at a lower
height.
à No complicated pendant-lines to be erected.
à Excellent choice for narrow sites in the city as there is no need to
pre-assemble the whole jib on the ground.
à Simple connection of jib sections with CJ Union system.
à Frequently only a CJ series Flat-Top crane will be the right solution,
due to limitations of conventional cranes with the extra height of
their cat-head.
à With the CJ series Flat-Top you get the maximum height under hook
with minimum overall height of the crane.
à On congested sites, additional CJ series Flat-Top cranes can
overlap each other adding only one mast section, thus keeping all
cranes at lowest possible height, with correspondent costs saving in
addition to minimization of mast sections, use of wall ties is often
avoided.
à Strong design, without alternating stresses in the jib, virtually
eliminates fatigue in this structure.
8. A new counter-jib for the CJ Series has been designed
to achieve a better crane performance.
à The wire rope capacity on the hoisting drums has been substantially increased to 790 or 620 meters with 3 layers on the drum for the 12t and 18t winch, respectively.
à The CJ series cranes have a shorter counter-jib
à The new counterweights are mounted from above and shelf-blocked with their own weight
à For installation and dismantling the counterweights are easily turned from their horizontal transport position to the vertical assembly position and vice-versa as the single lifting point is placed at their centre of gravity.
9. New reeving system with two trolleys, improves the load chart of CJ series cranes :
à With one trolley working in single reeving or two-part line, the crane gains load capacity at the front
of the jib and a bigger maximum load up to 18t is reached with two trolleys in double reeving operation ( four-part line) . Changeover from two trolleys to one trolley or vice-versa is done by remote control from the cabin and the trolley rope is automatically tensioned with every hoist movement.
à In simple trolley operation ( two-part line) , the primary trolley, together with the hook for double reeving
operation, rests on a steel structure at the foot of the jib, permitting completely independent movements of the two-part-line trolley.
10.Ã Intelligent inverter â not only knows the speed but the loads
à Potential meter control â
à Close loop control â Encoder system to feedback the motor speed to inverter, 2nd sensor to detect the actual speed and feedback to PLC , Should both speed is not in the same level, apply the brake either to control the speed or to stop the hoist.
à Position mode
High efficiency, reliable
Lower energy cost
Lower requirement on power supply
11.Advantages of Compacted strand rope against Round wire strand rope:
à Bigger metallic cross-sectional area
and higher breaking force
à Bigger contact surface between wires
à Stress on the wire are even and well-
distributed
à Higher structural stability in anti-
lateral load ( radial pressure)
à Minimize the effects of the larger
fleets angles on wire rope
à Smooth surface to portect sheaves
and drum
à Suitable for multi-layer coiling on the
drum
à Greater resistance to curshing forces
à Greater resistance to abrasion
12.Ã Frequency Inverter designed by Linden Comansa and Bonfiglioli Vectron
à Can give protocol interface, software and data setting to user for prompt service
13.Ã RCV Control
à Eddy current brake
à Soft start and stop
à Automatic gear change
à One separate power unit for each
motor, more stable and safe