Crowded skylines push tower crane anti-collision systems from option to requirement
Cities with dense high-rise pipelines are starting to require zoning and anti-collision systems on every crane with an overlapping jib.
When two tower cranes share airspace, the only thing keeping their jibs and hoist lines apart is often a radio call between operators. On sites where three or four cranes overlap, several city building departments have decided that is no longer enough.
Anti-collision systems give each crane a live model of its neighbours' positions. As two jibs converge, the system slows slewing and trolley movement and finally stops them before they reach a set separation. Zoning features also block loads from swinging over schools, rail lines, or occupied buildings.
Retrofits for older cranes
Most new cranes can be ordered with these systems from the factory. The bigger task is the rental fleet, where many cranes are more than 15 years old. Specialist suppliers now offer retrofit kits that fit sensors to the slewing ring, trolley, and hoist and communicate over a site radio mesh.
Contractors say setup time is the main cost: each time a crane climbs or a new crane goes up, the system has to be re-surveyed. Rental companies are beginning to include that work in their erection packages.
- Cranes
- Safety
- Urban construction
