50% more storage space thanks to pre-assembled energy supply systems in an indoor crane

• What was needed: Robust and reliable pre-fitted energy supply system
• Requirements: Low installation height, suitable for harsh environmental conditions, Reverse Bend Radius
• Product: readychain harnessed energy chain
• Industry: Cranes, indoor cranes
• Success for the customer: The prefitted energy chain solution from igus enabled Kranservice Herz to create 50% more storage space. 30% thanks to the sliding shelf solution and 20% thanks to the low overall height of the crane.

Such an automatic crane system for loading stainless-steel pipes is subject to special environmental conditions. Due to the structural conditions on site, the operator required an extremely low clearance height. The space from the top edge of the rail to the interfering edge of the sliding rack storage system is only 1,000mm.

Pipe bundles are automatically stored and retrieved in the racks and saved in a warehouse management program. A total of 24,000 storage and retrieval processes take place per year. To feed the automatic processing machines located in the hall, a crane places the requested tube types in a corresponding loading magazine of the processing machines. The pipes are then bent, turned and punched there and prepared for further processing. The ambient conditions are therefore a challenge, with oily air placing additional stress on the material.

There are many racks in a confined space and the crane travels over them into a very narrow aisle. In addition, turnaround times are fast and the clearance height of the hall to the top edge of the sliding rack is low.

The installation height of the crane girders with a span of 27.5m, the trolley, the slewing gear and the rigid load guide was not allowed to exceed 1,000mm. To find a suitable solution, the company developed a special interlacing method. This meant that the trolley with the trolley track was installed between the crane bridge girders, and the slewing gear was designed in such a way that it could be accommodated in the trolley frame without exceeding the height dimension (the upper edge of the crane bridge girders).

The power supply cables for the trolley drive and the slewing gear posed a further challenge. The installation space available for the trolley power supply is only 500mm high and 300mm wide. Conventional festooning or conductor rails were immediately ruled out due to the small installation height. The only option was to use energy supply systems via which the entire cabling of the main power supply for the drives, the control cable and the PROFIBUS cable could be guided.

Two reverse horizontal energy chains were used for the trolley power supply, which are located above the trolley frame on the inside of the main girder. The travels of the trolley power supply amount to 21,245mm for the first and 17,650mm for the second system. The speed is between 0 and 60m/min. For the slewing gear power supply, two reverse horizontally mounted igus energy chains are also used on the slewing gear frame. A rotation angle of 270° is achieved with this system. The speeds are 0 to 4rpm.

The four-part e-chain E4/4, series 3838 is used here as a pre-fitted readychain energy supply system with all the necessary cables. In addition, the entire trough material is supplied, including both standard troughs for the energy chain in sliding applications and special troughs for the chains with reverse bend radius.