Topic: VOC – Where is it all headed?
Lemken GmbH & CO. KG
Lemken GmbH& CO. KG – Who are they and what products does the company make?
Lemken is a globally operating manufacturer of agricultural equipment for soil cultivation, sowing and plant protection. Its main sites are located in Alpen, Nordrhein-Westfalen, Meppen in Niedersachsen and Hetzrath in Rheinland-Pfalz. The company produces and develops among other things ploughs, harrows, packers, cultivators and add-on sprayers. Lemken generated revenues of around €200 million last year and employs about 700 people.
What kind of a role does surface quality play for these products?
The surface of farm equipment plays a much greater role today than it did a few years ago. The market is demanding high-quality and long-lasting surfaces for their machines due in no small part to the extremely high investment costs for such equipment.
Which painting procedures were used in the past at Lemken?
Until 2009, painting was performed with a conventional dip process with Hydro deposition coatings.
Why there was a thought about surface treatment?
This kind of coating doesn’t meet the increasing corrosion protection demands our customers request for their surfaces. Furthermore, drips and paint accumulations adversely affect the appearance. Insufficient UV resistance and the long curing times required by the old paint system were further points to consider.
Which options were there for improving the quality of the products’ surfaces?
There were basically three possibilities:
The first was a cathodic dip priming (CDP) with a subsequent powder coat.
Second was a CDP and subsequent wet coat.
And lastly a CDP acrylic one coat system.
Why did Lemken choose the CDP acrylic one coat system alternative?
We have parts that have a thickness of 100 mm due to the large size of the products. With a dual coat system this would require heating and cooling these parts twice, which would have meant a reduction in capacity for such thick parts as well as a considerable increase in energy consumption and the size of the application system. The CDP approach has to be considered as inappropriate due to the complex shape of our components what makes automation quite complicated. The CDP and wet paint method was eliminated due to drips and paint accumulations.
The alternative one coat acrylic CDP method with its UV resistance enabled us to coat our products in one step. Parts are heated only once with a 50 µm coat applied in one coat.
What advantages resulted from an environmental or financial perspective?
On the one hand, the one coat system enables major savings in terms of the required technology. On the other, it saves about 50% on energy consumption. On top of all that, it also clearly reduces solvent emissions. All of this combines to preserve our limited resources and protect the environment. That is an important goal for a company making equipment for agricultural use.
Can the savings be quantified in euros and cents?
Yes. With about 200,000 square metres of coated surfaces and roughly 15,000 tons of paint, energy savings amount approximately from €100,000 to €150,000. Process-related costs that are being cut due to the shorter system operating times cannot be precisely calculated.
What investments were needed to convert to this type of surface treatment?
A completely new application system had to be acquired. We also had to develop a paint system and the corresponding process technology with which we could fulfil the high requirements on surface quality.
How was DuPont CoatingSolutions involved in the process?
DuPont CoatingSolutions played a strong role in planning, developing and commissioning along side of the system manufacturer B&M and Lemken. As a consequence, DuPont CoatingSolutions’
Were additional energy saving measures implemented along with the new painting system?
A comprehensive energy saving concept was implemented alongside the construction of the new painting system in 2009. The centrepiece of this programme focused on so-called energy rings which reclaim and reuse energy at various points in the painting system by using heat exchangers. In addition, surplus heat warms the assembly halls. The soil is also part of our energy saving concept – it is used as an energy supplier and energy store (geothermal energy).
Did the conversion of the painting process have any effects on production?
Production had to be completely redesigned – switching from painting after assembly to assembly after painting. This of course required some major changes in plant logistics and led to investment costs of about €25 million.
Were there any effects on personnel?
Yes, there was some work to be done there as well. Employees needed to be made aware that assembly of the painted components now required more care. Alignment work can no longer be done with the hammer for example. Another effect is that screws, nuts and fittings are no longer painted, but rather galvanised and given a silver surface. This in turn gives the products a higher quality look and feel. And this offers advantages when it comes to repairs as painted screws lose their coating with repeated screwing, damaging the overall aesthetics.
Do you see any further potential for optimisation in terms of environmental responsibility or financial efficiency in painting?
Yes, because the development of the coating material is steadily improving. We want to further reduce the curing temperature, use more environmentally sound materials and continuously enhance the performance of our coatings in terms of corrosion and UV protection.
What kind of support do you expect from DuPont CoatingSolutions in this matter?
We expect an ongoing dialogue with our paint system partner. They should identify our needs and support us in the continual optimisation of our products by providing their innovations in paint technology. We also expect test series to be conducted – even here on location. It is also important that DuPont CoatingSolutions adapts its paint system accordingly to new products. And last but not least, we expect a constant monitoring of the CDP dip parameters from DuPont CoatingSolutions laboratory.
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DuPont CoatingSolutions offers industrial coatings and automotive paint for all application areas, surfaces and substrates.
For more information, visit the website http://www.coatingsolutions.dupont.com.