Demag Cranes & Components has implemented an integrated intralogistics solution for handling heavy loads, serving workplaces and assembly at Siemens in Görlitz, Germany. Two process cranes, three standard overhead travelling cranes and seven wall-mounted slewing jib cranes support the entire production process on three levels in a new assembly bay for turbines. The crane installations are used to stage the parts to be installed at the workplaces, help with assembly work and are used to transport the turbine packages, which weigh up to 190 t, to the goods-out area when they are ready for shipping. The owner benefits from optimum utilisation of the available space and more efficient operating processes.

Siemens responded to growing demand for industrial steam turbines with the construction of a new assembly bay measuring 3,000 m² in size. In the new bay, every order is assigned to a specific assembly station, where the turbine elements are installed step by step until it is completed.

Two process cranes fitted with MPW open-winch crabs and with a span dimension measuring 24 m operate on the upper level. The crane which has a rated load capacity of 80/32 t transports turbine parts such as the base frame. The larger crane, which is fitted with a main hoist unit with a load capacity of 200 t and a second hoist unit with a load capacity of 100 t, is also used to transport the finished turbine packages. The cranes are each fitted load-dependent speed control for the lifting motions. This arrangement facilitates precise handling and exact positioning – right down to the last millimetre. At its rated load capacity (200 t), the main hoist unit has a lifting speed 0-2.1 m/min, and 0-3.3 m/min for partial loads (up to 112 t). For loads weighing up to 59 t, the second open winch unit lifts and lowers at speeds of 0-5.0 m/min and at 0-3.1 m/min in full load operation. Cross travel is performed at speeds of 0-20.0 m/min by both crabs, crane long travel is performed at speeds of up to 40 m/min.

To achieve more efficient operating processes, the two crabs of the large process crane are designed for safely turning workpieces. In the past, it was only possible to carry out this operation, which is necessary for some turbine types, together with a mobile crane.

In order to save time, the cranes were also provided with an exact load weighing system. This enables the total weight of a package, which is only theoretically determined in advance, to be reliably calculated during the assembly phase. If necessary, this arrangement makes it possible to update a previously issued transport permit in good time in order ensure that the transport schedule, which has to be planned long in advance, can be met.

On the middle level, three standard overhead travelling cranes of double-girder design ensure that the 20 assembly workplaces are replenished. The cranes have a span dimension of 23.1 m and load capacities of 20/12.5 or 32/16 t. The space-saving design of the crabs that were fitted with DR-Pro rope hoists enabled additional lifting height to be achieved. Inverter-controlled operating speeds in all three directions provide for safe and reliable transport and gentle handling of the loads. The lifting speeds range from 0.5-8 m/min. The crabs travel at speeds of 5-25 m/min, while the infinitely variable crane long-travel speeds range from 3 to 40 m/min.

On the lower level, seven wall-mounted slewing jib cranes each with a load capacity of 1,000 kg are used to support the assembly work. The 5 m-long jibs can be manually slewed through 180° and are fitted with DC-Pro travelling chain hoists, which are operated by means of DST control pendant switches. To save space, the cranes are fitted to pillars in the building, which leaves the floor area completely free for assembly work.

The decision to install Demag cranes throughout the bay was also based on the good experience already gained with products supplied by Demag Cranes & Components at the location in the past.