Cormach cranes are designed right!
All Cormach cranes have the same constructive concept:
- Column with twin mast. Big dimensions slew bearing with rotation motor placed in external position, and gerabox.
- The slew bearing is installed on base of the crane. Cormach desing allow the stress distribution and prevents stresses concentration.
- The cantilever structure with the double column distribute stresses and shocks on the big dimensions slew bearing and through the bearing to the stabilisers and then to the ground thanks to the chassis that acts as a counterweight.
- • The double sandwich structure of the double column is calculated to resist the torsion stresses created by the rotation and absorbs the shokcs created by sudden movements.
Cormach design calls for stress dissipation, not stress concentration.
- The cantilever profile of the twin columns dissipates the lifting stresses and shock loads evenly into the big slew bearing and, through that, into the outriggers and to the ground, with the chassis acting as the counterweight.
- The box cross-section of the twin columns is calculated to handle torsional stresses created by abusive slewing, and to absorb the shock and sudden stops, starts and reversals.
All single column cranes have an unavoidable point of big stress at the upper bush. This is overcome by the use of very thick steel walls in the turret. This inevitably has excessive torsion rigidity that transmits all the rotational shocks of poor handling straight into the pinion. If you make a truck chassis rigid, and prevent it flexing to absorb shock, you know that its life will be substantially reduced. The same is true of crane design.
The Cormach System.
Most knuckleboom crane manufacturers use the Cormach system with slew bearing and turret for their big, high capacity units. Only Cormach uses this system on their entire product line. From this fundamentally sound design arise many advantages:
- Symmetry about the centerline is achieved.
No Cormach has off-set columns or booms.
This results in evenly distributed loads in all pins, bearings and bushes.
- Low center of gravity – Cormach cranes have their heavy components down near chassis level to give a low center of gravity.
- Continuous slew rotation – is standard from 38 tonne meter cranes and upwards, and optional on all smaller models. This is not possible with rack and pinion rotation.
- Two cylinders – one on either side – are used to raise the main boom for optimum stress dissipation. Either could support the load in an emergency.
- Lower crane weight – Due to the design, Cormach cranes are usually substantially lighter than competitive models.
- Less mounting space – Cormach design takes up less chassis frame space than competitive models.
- Easier Safety inspections – parts are all open to view.
- Easier Maintenance – much easier with the “Big Crane” design
- All parts are visible
- All wear is measurable
- All leaks are immediately traceable