Swing-Rotator-Grapple for truck cranes

What are the requirements involved in loading with a truck crane?

Modern truck cranes are fast and powerful. The stresses generated differ from those in forest machinery. Although loading induces fewer load reversals, greater loads are moved at any one time.

1. Short timber transport: When loading short timber, the timber grapple must penetrate the deck easily and bundle the logs neatly – and not play jackstraws. A good filling ratio reduces the loading time. The timber grapple should not be too heavy and yet be able to handle a 4 t payload.

2. Long timber transport: Loading long timber depends greatly on enclosing completely the thick logs and holding them reliably – the log may not move in the grapple, nor the grapple be forced open. Transporting thick beech may encounter logs up to 10 t in weight. Handling these logs requires the best material strength. At the same time, the timber grapple must be compact enough to pick specific logs out of the deck and to deposit them precisely in the right place. Here too, the timber grapple’s optimal geometry is decisive. The rotator and the swing link must be able to bear the greatest loads handled by the most powerful long timber cranes. Owing to the high forces generated by loading truck cranes and the associated safety requirements, the quality of the grapple, rotator, and swing link has a decisive effect on the cost effectiveness of the timber truck.

The combinations of crane damping, forestry rotator, and timber grapple we recommend for truck cranes: