Flexibility in a four-pack

The steel construction company Haslinger from Aldersbach-Uttighofen near Passau manufactures not only cranes but also platform constructions, landings and staircases. The crane construction partner of Stahl Crane Systems primarily realizes customer-specific crane systems using standard crane components from Stahl Crane Systems. One project at a German car manufacturer in southern Germany involved the design, production, delivery and installation of a total of four double-girder bracket cranes. In the first step, two systems were initially planned for a hall in which large tools for the production of car body components are checked and processed. There were already older bracket cranes here, each with a lifting capacity of five tons, but they were no longer able to cope with the future logistics requirements and were therefore to be replaced by new cranes, each capable of lifting eight tons.

More flexibility and performance in a large area

The construction of the specific bracket cranes proved to be a challenge. The four bracket cranes are an addition to an existing overhead crane and create a further movement level for various work processes. With a jib length of 8.40 meters each and a crane runway length of 80 meters, almost every area in the 1,600 square meter hall can be reached. The bracket cranes can serve all work areas simultaneously; the use of the main crane is not necessary.

During the two construction phases of the project, two bracket cranes had to be installed on one side of each hall. The crane runways were prepared and reinforced accordingly in advance,

to accommodate the loads of the new cranes. In order not to disrupt ongoing operations in the hall, the first two cranes were installed at the turn of the year 2020/2021.

Haslinger chose an SH 5025-20 electric wire rope hoist with a reduced load capacity of eight tonnes and a lifting height of six meters from Stahl Crane Systems' standard range as the hoist for one of the two double-girder bracket cranes. The SH series wire rope hoists are available in five sizes with 27 load capacity variants from 500 to 32,000 kilograms. The compact, low-maintenance solutions are suitable for stationary lifting work or with a trolley - in this case with a top-belt trolley with a maximum travel speed of ten meters per minute - in standard and special cranes. The standard wire rope hoists can be individually adapted to customer requirements and can be equipped with additional safety technology. The customer wanted the speed to be halved, which was solved with an intermediate gearbox. This means that greater precision can now be achieved when lifting and lowering loads at a lifting speed of five meters per minute.

Continuous recording of relevant operating data

A key component of the wire rope hoist is the SMC 22 multi controller for continuous load measurements with automatic load monitoring, which switches the hoist off immediately in the event of an overload. As a load collective memory, the SMC records various operating data in real time - such as the operating hours, full load operating hours, number of motor switching operations and other parameters that are relevant for the reliable and safe operation of the hoist. The operator can read out and evaluate the data using the Stahl Crane Systems Config Tool. The SMC can also be used to accurately perform the annual calculations required for the service life of a hoist.

Single and tandem operation with integrated load totalization

Although the design of the second bracket crane is identical to the first, it has some special features for which, among other things, the crane's statics had to be designed. Two SH 6040-10 electric wire rope hoists with double-grooved rope drums and 4/2 reeving, which prevents hook migration when lifting and lowering loads, travel on the top chord. The hoists, also designed for a load capacity of eight tons and a lifting height of six metres, can be operated either individually or in tandem, thus providing a high degree of operational flexibility. For tandem operation, load summation with a safety PLC is also integrated; it permanently measures and monitors the loads on both crane hooks and ensures that the crane's permissible total load capacity of eight tons is not exceeded. In tandem operation, longer tools can be transported more easily and positioned more precisely; the transported goods always remain in a stable position on both hooks and load sway is avoided.

Haslinger also realized a special design using standard endcarriages and wheel blocks for the travel axis of the cranes, which consists of three crane runways on each side of the hall. Each crane is equipped with two frequency-controlled travel drives on the lower endcarriage, which runs on the middle crane runway. Four wheel blocks are used to evenly distribute the high compressive forces on the lower crane runway.

http://www.metallbau-haslinger.de http://www.stahlcranes.com