Laser Cleaning, cleaning with laser light, literally knows no limits. The light penetrates into all areas and ensures effective surface treatment where it hits a workpiece in a concentrated manner. With the modern technology of laser blasting machines, it is now possible to solve many problem areas in the blast cleaning sector, be it due to very sensitive surfaces, the minimization of noise emissions and power efficiency, or the absence of additional blasting agents (dust reduction).
Lasering instead of blasting
Laser processing of parts has long since outgrown its infancy and has established itself in many areas as a robust, reliable method of surface processing. Especially when sandblasting reaches its limits due to the mechanical impact or the associated dust exposure, a laser system is increasingly being used. However, CO2 blasting (dry ice cleaning) for surface cleaning is also increasingly being replaced by suitable laser cleaning. This also saves the user the cost-intensive storage of consumables. The young company EraserLaser, based in Siek in the north of Hamburg, Germany, specializes in this type of laser-based surface cleaning. In addition to its headquarters in Germany, the company has branches in Spain, Austria and Hungary just a few years after it was founded. The applications are as diverse as the light beams used. The lasers for the systems and mobile devices are bought in, but EraserLaser emphasizes that the laser technology is made in Germany. The strength and design of the devices can be adapted to customer requirements.
Cleaning surfaces with lasers
The Laser Backpack is the ideal device if mobility is required when cleaning with laser light, for example to clean facades on a ladder or to be able to reach between components on large machines - (Photo: EraserLaser GmbH)Cleaning with laser light is not only effective and environmentally friendly, but also versatile. The general principle of cleaning is based on the removal of soiling or cover layers (such as rust) by vaporization. The use of pulsed laser systems is important here. This is the only way to minimize the thermal effect on the base material. Once the coating has been removed, the reflectivity of the surface changes, the laser beams are reflected and the ablation process stops. The process is so gentle on the material that even historical documents can be cleaned in this way. It is important to note that the surface itself is not altered (e.g. roughened), as is common in blasting processes, but retains its original structure. If structuring is desired, the laser parameters need to be adjusted accordingly. The directed laser beam offers some interesting possibilities. For example, a surface can only be partially activated, which opens up a wide range of applications for selective electroplating. In general, cleaning with laser light is particularly suitable for removing homogeneous and localized layers from a metallic base material. The physical properties (especially the absorption behavior) of the coating have a decisive influence on the process. All materials have a so-called ablation threshold. This is the minimum power or energy density at which ablation is possible (at a given wavelength and pulse length). This limit is material-specific. If the intensity generated by a laser is above the ablation threshold of the material, the material is ablated. However, if the intensity is below the ablation threshold, nothing happens apart from a slight increase in temperature. The speed of ablation depends on the adsorption properties and the thickness of the material to be ablated. The so-called area rate is significantly higher for thin oxide layers, for example, than for thicker layers of paint and varnish. Thick rust coatings may also require a two-stage process. The materials that are ejected from the surface evaporate into fumes. Although these fumes are minimal, fume extraction is usually required near the laser to prevent build-up and obstruction of the light beam. Although the removal of coatings thicker than 0.5 mm is generally considered uneconomical, especially for large surfaces, it can still make sense for machine maintenance.
Stationary systems or mobile solutions - everything is possible
The laser systems can be easily integrated into existing systems and are therefore available around the clock for low-maintenance surface processing. With Class 4 laser sources, a laser safety officer must be appointed in addition to structural safety measures in accordance with current European law. In general, EraserLaser relies on consultation and training to ensure safe and efficient operation of the systems. Applications are developed and processes optimized together with the customer. This also applies to the mobile devices. For example, backpack systems are offered for system cleaning. This laser backpack is the ideal device for reaching higher system parts on a ladder, for example, or for reaching between components when cleaning large machines. Everything needed for laser cleaning is integrated in the backpack, a small touchscreen for the settings and the laser gun with holster are also included in the compact package. There is a choice of 50 or 100 watt lasers. From mobile cleaning and use in a workshop to use in industrial production, all areas of application are well covered. From weld seam cleaning to maintenance, degreasing of surfaces and activation, laser cleaning offers a flexible working method for countless applications.
