Swabian machines for exceptional tasks

Reading time: min

The finest features for the extension of the Holy Mosque in Mecca are created on SHW machine tools

When the remodelling and extension of the Holy Mosque in Mecca are completed in 2018 then one German company will have made a significant contribution towards it. The doors, gates and façades, as well as the balustrades, ornaments and gilded ceiling light systems come under the responsibility of RIVA Engineering from Backnang. The dynamic and growing company has entrusted a record contract to SHW Werkzeugmaschinen by commissioning ten travelling column machines from this established supplier. These are breaking new records in the machining of huge workpieces made of sophisticated materials.

"We are producing elements made of metal for the buildings of the Holy Mosque in Mecca with high demands visually. They must be rendered durable in the harsh climatic conditions," explains Klaus Rasch, process engineer at RIVA GmbH Engineering in Backnang. To accomplish this, the dynamic, growing company has recently commissioned ten travelling column machines including a compact machine from SHW Werkzeugmaschinen, which in 2013 was the largest contract awarded to the established supplier from Aalen in the 650 years of company history. The delivery included four PowerSpeed 6 series travelling column machines with head changing system and with two columns for synchronous or parallel processing. "It is actually two machines that communicate with each other", explained Christian Hühn, Managing Director of SHW Werkzeugmaschinen. The parallel processing of large, hard-to-handle workpieces saves RIVA a lot of processing time and increases productivity and quality in a single setup. In addition, a PowerSpeed 5 and UniSpeed 6 from SHW WM have also been installed in the huge, newly built pristine halls, which glisten under their clean and open architecture and glass façade.

Major project with tight schedules drives dynamic growth

At first sight the sheer size of the machine tool facilities and halls is awe inspiring, and the SHW machine tools are only just part of the entire machine inventory. As the viewer gapes in amazement, a whole host of further machine tools from German manufacturers catches the eye. An effect which is repeated with the third hall currently under construction and an adjacent site for a fourth hall. "Everything has to be ready in Mecca by 2018. So time is of the essence," emphasises Rasch. The SHW machine tools machine aluminium and the complete range of stainless steels right up to high strength and extremely difficult to machine duplex steels. The large workpieces, which are processed on the machines, have a maximum size of 12,000 x 2500 mm. For this, the machines are equipped with the automatic universal milling head in orthogonal design and the fork head with high frequency spindle.

For the extensions of the Holy Mosque in Mecca, RIVA GmbH Engineering is manufacturing doors, gates and façade elements with integral insulating glass units up to 15 meters high as well as balustrades, ornaments and ceiling lighting systems. Although it all sounds somewhat mundane, on closer inspection it turns out to be a highly challenging task. The delivery includes double leaf swing doors up to 6.30 m wide and almost 7 m high, and four leaf doors made of glass up to 16 m wide, where each leaf has a glass element weighing nearly 4 tonnes circumferentially mounted in massive frame profiles made of duplex steel. The doors, weighing a total of 100 tonnes, have to work absolutely smoothly in the harsh climatic conditions of the desert with sand and dust and temperatures below 0° C at night and up to 50° C during the day. Ultimately, they should direct the flow of pilgrims and in case of danger quickly close or open, in order to effectively prevent cases of panic.

Stainless steel profiles are gilded as a finishing touch

The SHW machine tools are ideally suited for heavy duty machining of large work pieces. Each door consists of twelve main parts and a multitude of small parts, with four profiles for each door leaf, side supports and floor plates, as well as a lintel across the entire width of the door, in which the leaves are guided. "It just fits on the machine table," explains Michael Lutz, project manager at SHW Werkzeugmaschinen. The lower profile of door surround weighs about 800kg before machining and about 500 kg after the milling and drilling operations. This therefore requires a high performance for the chip management. The chips are sorted separately into stainless steel or aluminium, directly on the machine, and then transported away. A system is installed for cooling lubricant supply for every two machines. After machining, the workpieces go for grinding, polishing and gilding. The highly polished stainless steel parts are plated with a 3.5 micron thick layer of pure gold.

For the interior lighting of the Holy Mosque in Mecca, RIVA GmbH Engineering is providing the direction control for more than 12,500 linear meters of lights. The lighting grid from RIVA is by no means made of thin sheet metal. Using the SHW machine tools, RIVA is milling the classic oriental designs out of solid stainless steel, before they are then gilded. As Klaus Rasch explains, "Quality is the most important thing. Everything should not only look beautiful, but also remain durable." This also applies to the façade elements, which have been incorporated in large quantities in planning the huge extensions. Pairs of 70 mm thick aluminium plates, measuring two times approximately six meters, are also milled with classic oriental designs before each one of the pair is fitted with a glass panel or a "bird mesh" in the centre and then integrated into the façade.

With a traverse speed of 30,000 mm/min., the double columns of the PowerSpeed 6 travel along the 14,000 mm long traverse distance quickly to any part along the 12,000 mm length of the workpieces. The headstock moves vertically in the Z direction up to a height of 2100 mm and horizontally in the Y direction up to 1500 mm in the customer specified rotated coordinate system. For over 50 years, the core element of the SHW machines remains the compact and powerful automatic universal milling head in an orthogonal design. Using the articulated milling head more than 216,000 calculated positions of the workpiece can be approached quickly and with exact precision, as a result of the 180° rotation range of the A-axis and 360° of the continuously variable C-axis, as used in versions with the head changing system. The compact head pivots automatically to any desired position. "This provides exactly the flexibility and high machine availability of over 90 percent, which we need for the frequently very short-term production schedules", remarks Rasch.

Reliability of the machine builder is extremely important

As process developer, he is responsible at RIVA for machine design and selection. "The proximity of SHW was and remains immensely important." Citing key criteria, Rasch believes that: "The short journey is, therefore, just as important as service availability and support through a single point of contact." Similarly the reliability of supply, which the Aalen based company could ensure, was a big plus. As Klaus Rasch further adds, "We took care when choosing the machine manufacturer that they can also 'cut it' and not just make promises:" which is exactly how SHW Werkzeugmaschinen reliably delivered and installed the machine tools. "Nevertheless the contract represented a great challenge for us," noted Managing Director Anton Müller. At times, one half of the production area at Wasseralfingen was totally occupied with it. The schedule was so tight that the highest demands were also placed on the delivery by truck and the complete installation of the machines by the 20 technician strong, multiple installation teams. At the same time, as the commissioning of a system was still in progress at end of the hall, machining was already being carried out on the first machine in the hall. As Michael Lutz recalls, "When we installed the first system behind temporary partitions, the floor at the other end of the hall was not even ready."

Machining processes are used for live broadcast

The erection of only German machinery in the production halls might seem surprising, but there is a simple reason, as Rasch explains: "Our customers expect 'Made in Germany' quality, which is why only the best technologies of the highest quality are used." This is something that impresses representatives of the customer when they personally visit on site. They occasionally come by to inspect the progress of the contract. This also explains why large blue or red RIVA lettering, signalling the operating status of the machines from a distance, are hung on the enclosures of SHW systems, as well as huge flat screens, which transmit the current machining processes through high-resolution cameras. "As a result, our customers thus have the opportunity to experience live machining processes without having to enter the machine shop." RIVA is very satisfied with the output of SHW machines.

The RIVA Group

RIVA Engineering is a global provider of engineering services and producer of metal structures. RIVA implements projects in façade design that combine economic and architectural challenges. The product portfolio of RIVA GmbH Engineering includes the planning, design, manufacture and installation of building façades and technical equipment. The energy balance in such projects play a central role and is also manifest in the areas of focus of the younger RIVA companies. For example, experience in the fields of energy technology, photovoltaics & solar technology as well as other areas, is applied in the RIVA Energy company to support communities with integrated energy systems. This distinct energy focus is complemented by the development of efficient storage systems, which is the main area of activity of the RIVA Batteries company.
Another major current theme in respect of energy is "LEDs". A number of companies belong to the RIVA Group, which develop and produce LEDs and integrated them into efficient lighting systems for the commercial, industrial and municipal sectors. These companies include Alder Optomechanical in Taiwan and RIVA Lighting, LIGHTS and Cenit Leuchten (all in Germany).

Source: SHW Werkzeugmaschinen