The SMS group name is synonymous with tailor-made concepts for metallurgical machines, plants and services. At its Monchengladbach facility, machine components are manufactured in various sizes for pipe systems, ingot rolling mills, as well as pressing and forging machinery, with some of these components being pre-assembled into modules. The paint booth was also modernized as part of the project to refurbish the entire building.
Until now, SMS group had painted all parts in an open area within the hall. Dürr completely redesigned this open area and created a self-contained zone in the new paint shop which was designed specifically for painting large components. Smaller parts are painted, as before, in another open area.
At the design stage, it was important for the company that the new painting zone fit into the existing hall layout. As large-scale machine parts are also painted, the plant designers at Dürr were faced with the task of making optimum use of the available space. The large workpieces are unloaded by crane, for example; a fact that was considered during the planning phase. In addition, a standard-configuration paint booth requires more handling space than was available in the hall.
Three-part telescopic booth
Dürr met these challenges by means of a telescopic paint booth. The large parts to be painted are positioned by crane in front of the telescopic booth in its contracted form, which has a length of about six meters. An operator then extends the three-section telescopic booth until it completely surrounds the parts to be painted. In its extended form, the booth measures 18 x 8.5 x 5 meters.
The telescopic booth is classified as a large-capacity paint shop and is used in the manufacture of trains, commercial vehicles, and other oversized objects. At SMS group, these objects include machine components in various shapes and sizes. The booth was manufactured at the Dürr facility in Karlstein, Germany, and can be used for various operating modes such as painting, cleaning, standby, and drying.
Painting the machine parts covers the complete work cycle from cleaning, priming, topcoat application and preservation, to the application of anneal-resistant paints. The paints (1 or 2component, water or solvent-based) are applied manually in the booth using an application set. The set consists of high and low-pressure pumps with the associated manual EcoGun spray guns. For smaller quantities of paint, Dürr spray guns with gravity cups are used.
Delivering paint by means of pumps is particularly suitable for covering large areas with thicker coats. Dürr pumps can deliver a very wide range of materials. In the case of liquids such as water and solvent-based paints, the horizontal piston pumps EcoPump HP and EcoPump HPE are used. For medium to high-pressure applications, for example when paints are applied using airless or air-assist systems, the EcoPump VP, a pneumatically driven, vertical piston pump is used. Thanks to their modular structure, Dürr pumps are very easy to maintain and meet the highest quality standards. As a matter of principle, Dürr manufactures all its pumps in Germany and tests them on its own fully automated test bench in accordance with the DIN EN 12162 safety standard.
"Thanks to our wide range of products, we are able to offer and implement complete paint shop systems, including application and paint supply", stresses Bernward Keller, Manager for Proposals at Dürr Systems GmbH, adding: "The principle of 'one-stop shopping' is very much appreciated by our customers."
High energy efficiency
In the metalworking industry, there is enormous potential for saving energy, so the matter of energy efficiency plays an increasingly important role in this sector. SMS group also attaches great importance to low energy consumption for its own plants and systems. Dürr took this requirement into consideration when designing the new paint shop. The telescopic booth is heated directly without a flue gas duct. This means there is no heat loss, as all the energy is converted into heat. The heat recovery rotor system that is also installed recovers about 66% of the lost heat and thus reduces the consumption of primary energy (natural gas) in painting and standby modes.
An extraction system is also integrated which absorbs the solvent emissions, thereby guaranteeing that the ambient air complies with the stipulated DIN standards.
Open area painting
Two additional areas of the hall (each measuring approximately 9.2 x 5.8 m) are used for painting other large and small components. This zone is structurally connected to the telescopic booth. Here too, Dürr application technology is used. These two areas are ventilated by means of long-throw nozzles immediately under the hall roof which blow air down from a great height. This flushes the parts to be painted with clean air, while the emission-laden outgoing air is extracted through ducts in the floor. In this way, all conditions in the hall comply with the workplace directive.
In service for over a year
The solution offered by Dürr focused closely on the customer’s requirements when the plant was being designed and integrated. The existing hall footprint served as a basis, so that SMS group only had to carry out minor structural alterations. The equipment room, which is now located outside the building, was integrated both visually and technically into the hall.
The complete conversion took place within four months in parallel with normal operations and demanded a high level of flexibility from all those involved. Since then, the plant has been running for more than a year and has passed its practical tests. "We are very satisfied with the way the project was implemented and with the reliability of the plant. Dürr has proved to be a competent partner who has understood our needs and thus found the best solution for our plant concept", says Wolfgang Rodde, General Manager Workshop Assembly, SMS group GmbH, in summing up the conversion work.
Dürr covers the entire bandwidth of paint application, both in the automobile sector and in industry in general. Apart from large-scale systems, Dürr also builds automated paint systems in which smaller parts to be painted are carried on a chain conveyor. Customers include major manufacturers of products made from plastic, glass, metal and ceramics. All standard components, such as nebulizers, color changers and dosing systems are part of the portfolio. Dürr offers these components as individual products or as standardized packages.
Bolstered by the acquisition of the companies Bersch & Fratscher (Germany) and EST+ (Czech Republic), Dürr is now well positioned to fulfill any requirements customers may have.
Exhaust air purification also by Dürr
Many painting processes still use solvent-based paints. If solvent emissions in excess of five metric tons per year are generated, a corresponding exhaust air purification system is a statutory requirement. Dürr also offers its own solutions for this problem. Using standardized, energy-efficient exhaust air purification systems, the legal requirements can be met with comparatively low capital investment and operating costs.