Kühnezug

Oval girder

The astounding stability of an eggshell inspired us to develop and patent the oval girder. An eggshell exhibits enormous resistance to longitudinal forces, despite its very low wall strength and low weight.
Our patented oval girder imitates this high-strength form and uses its high stability optimally for crane construction.

OVALplus


In comparison with traditional hollow box or plain girders, the oval girder has a number of advantages:

  • The central force introduction into the oval cross-section of the girder results in significantly better distribution of force over the walls of the girder than is possible with rectangular hollow box girders.
  • The especially high stability of the oval girder reduces its intrinsic weight and thus also loads on the wheels. This feature reduces costs in building construction or allows greater load capacity for an existing building.
  • Oval girders have no weak points due to welding seams at the edges of the girder. That avoids potential breaking points.
  • The oval girder is also ideal for outdoor use: The aerodynamically advantageous shape, channels the flow of air and offers less surface of attack for wind and weather. The lower wind stresses are also easier on the drive units.
  • The round shapes of the oval girder reduce collections of water and dirt, thus effectively prevent the formation of rust.
  • Due to the structural advantages of the oval girder, spans of up to 50 m can be reached in a single-girder design (OVALplus*). Traditional hollow box girders often require a two-girder structure even at a 20 m span.
  • In the OVALplus* single-girder overhead crane, the hoists move along the side of the girder with a special trolley. This provides advantages in terms of installation dimensions and lifting height achievable in comparison with conventional designs.
  • The particularly small installation dimensions ensure better utilisation of your building volume. That reduces your costs in building constructions and heating.

Our products with the unique oval girder:
Overhead travelling cranes
Automatic cranes
Gantry cranes
Pillar jib cranes