Summary and conclusions

Brancheindsats for produktkæden ”Korrosionshindrende overfladebehandling af store stålkonstruktioner og skibe”

The objective of the project is primarily to promote the use of more environmentally friendly and working environment friendly materials and methods in the heavy duty industry. The objective has been advanced in cooperation with paint producers, application equipment producers, painting contractors and consumers.

The specific objective with this project is:

The development of a mobile robotic plant for automated application of paint to the exterior of wind turbine towers that will result in savings in consumption of paint, reduction in the emission of solvents, reduction in energy consumption, reduction of working time harmful to the working environment and in a uniformly high quality.
The development of application methods which can be used for automated application of paint to the wind turbine towers.
Information project and supplement to ISO 12.944.

Conclusion part project 1 – Automated application of paints to wind turbine towers

The final result of the test setup indicated that there were immediate advantages by using robots for the application of paints.
The project has shown that the internal application of paints to wind towers is also possible with mobile robots.
This will give a uniform application.
There are significant savings to be made in the consumption of paint and this will give a calculated annual saving of approximately 90,000 kg solvents having an impact on the environment. This is the equivalent of a saving of approx. 40%. The paint saved will also give a reduction in pollution through less production and fewer litres of paint transported. The figure is based on an annual production of 840,000 sq. metres distributed over 50% completed according to a C3 system and 50% according to a C4 system in accordance with DS/EN ISO 12944.
There are significant improvements in the working environment since no surfaces are painted by hand apart from protruding areas.

A finished plant for the surface treatment of sections of towers for wind turbines has now been installed. The plant which has been process automated is the first of its kind in the world. The project supported by the Danish Environmental Protection Agency has resulted in the following project and investment on a full scale with DS SM A/S in Rødekro.

Conclusion part project 2 – Development of alternative application methods

Trials with the 6 different application principals, cylinder application, carpet finishing, roller application, traditional airless spraying, Airmix spraying and wetting have shown that there are environmentally friendly alternatives to the traditional airless application of paint, and that the process can be automated using very simple equipment.

It has turned out that the simplest way forward will be to use a type of Airmix spraying with as large a nozzle and as low material pressure as possible. This principle will give an environmental and correspondingly financial gain of a minimum of 20% by changing from airless to Airmix spraying due to the improved application efficiency (less paint spraying missed). By automated application a smoother thickness is obtained compared to manual application.

The advantages in the working environment by changing from manual spraying to automated surface treatment are obvious.

Conclusion part project 3 – Information project, Supplement to ISO 12944

A collection of examples of more environmentally friendly paint systems has been developed. The collection of examples is generic and was published in the autumn of 2009 by DS publishers as a DS leaflet to ISO Standard 12944 – 5.

As a supplement to the DS leaflet, ten case studies have been developed that deal with the advantages both for the environment and for the working environment, but it also deals with the disadvantages there may be in using various water based paint systems.

To acquire a better understanding of where and how the application of environmentally friendly paint for large constructions such as bridges, tanks, masts, ships etc. is possible, an appendix (D) has been compiled “The prevention of corrosion may also be environmentally friendly”, which describes the overriding requirements to the paint application systems. In some cases it is possible to choose a pure water based system, for others maybe a solvent free system or a system with a low solvent content.

All the objectives of the project have been reached.