With 45 new manual welding stations in a new shop, Knoll Maschinenbau GmbH has achieved a lasting efficiency improvement in this sector. 

Twenty-seven single-girder suspension cranes from the KBK crane construction kit supplied by Demag Cranes and Components are used to turn the steel containers to be welded into the optimum ergonomic positions.
Knoll Maschinenbau is a leading supplier of filter installations for swarf and cooling materials in the metal processing industry. Positive displacement pumps are also used in the chemical and foodstuffs industries. “With its comprehensive range of products, complete installations and system solutions are implemented with central or decentralised functions. Knoll has stood for innovation, progress and growth since 1970,” a statement said. The company, which has 600 employees, supplies across the mechanical engineering sector.
In the scope of its “effective factory” project launched approximately one year ago, Knoll is closely examining all manufacturing processes. The goals are shorter throughput times and lower inventories. This also applies to the welding shop. In order to improve its efficiency and, therefore, to meet the strong demand, Knoll has extended working hours to two shifts and invested in a new bay. The building covers an area of some 5,000 sq m. The friendly and brightly lit, very clean bay is a pleasant and motivating working environment.
Knoll utilises 27 single-girder suspension cranes from the KBK crane construction kit supplied by Demag Cranes and Components at 45 welding stations in the new building. The majority of the cranes have a load capacity of 500 to 750 kg. The KBK system is used to turn steel containers, which weigh between 20 and 500 kg, into an optimum ergonomic position for welding. The welders do not need any external help, since they can each work with two cranes.
 Experience from project engineering for other bays was incorporated in the planning. Cranes made of KBK II profile sections were initially intended for the new building. The company wanted to relocate them from the old welding workshop to the new one. However, for static design reasons – the span is greater than 5 m – the decision was changed in favour of the KBK III outside-running profile section. This has a load capacity of 2,500 kg; with a distance between suspensions of 1 m, it can reach 3,200 kg Compared with the KBK hollow-section profiles, KBK III offers better stability and deformation characteristics for higher load capacities and larger span dimensions. The profile section is also suitable for automatically controlled installations. In this case, it is fitted with four to 10-pole DEL conductor lines.
The KBK system developed by Demag requires only a few standard modules for a wide variety of cranes and suspension monorails, regardless of whether they are used for a simple suspension monorail or for complex area-serving material flow solutions. The profile sections of the crane construction kit are available in steel and aluminium. Components from the KBK ergo range are available to accommodate the kick-up forces that occur in connection with handling devices. Various profile section sizes and materials can even be combined within a crane installation. Whatever the variant, one factor always remains the same: the cranes utilise the free space beneath the ceiling, thus leaving floor space free for other productive activities.
Knoll awarded the contract to Demag Cranes and Components because the two companies have been working together for 20 years and the customer has gained positive experience both with the KBK crane construction kit as well as with the supplier’s sales and service employees. So far, Demag Cranes & Components has installed some 155 KBK suspension cranes in Bad Saulgau, Germany.  They are used at all workplaces, for example in the switchgear cabinet shop and in the assembly line. “The favourable price-to-performance ratio also spoke in favour of the KBK system. Furthermore, the alternatively considered plan to use forklift trucks would have been combined with much higher personnel costs,” the statement said.
Knoll concluded a maintenance agreement for all of its crane installations with Demag Cranes and Components at the end of 2006.  “The contract guarantees an availability rate of almost 100 per cent,” the statement said. “If, contrary to expectations, a malfunction ever occurs, it will usually be quickly rectified by the customer’s maintenance department, particularly in view of the fact that the company keeps its own stock of the most common spare parts. This was a further reason to decide in favour of the KBK crane construction kit once again. Concentrating on one system makes it much easier to maintain stocks of spare parts.”