Robotic surface preparation for extreme weather resistant coatings

For a global fire door manufacturer which – with its existing manual surface treatment process – was unable to meet high standards in terms of coating adhesion, something which is essential for users living in extreme temperature conditions (humidity, heat, low temperatures…), FerroEcoBlast® Europe, a company based in Dolenjske Toplice, Slovenia, designed and manufactured a robotic blasting chamber ROBOBLAST 35-25, which delivers a fully automated and controlled sandblasting process and gives the treated surface uniform roughness, which is crucial for achieving improved coating adhesion. By doing so, they have enabled the Slovenian-based company Vrata Deržič to enter the niche market for the most advanced fire and waterproof doors aimed at the world’s most challenging markets in climate terms.

A Dolenjske Toplice-based family business with more than 55 years of tradition, FerroČrtalič develops and manufactures machines for cutting-edge surface treatment technologies, which are marketed under their proprietary FerroECOBlast® Europe brand. With a strong focus on developing comprehensive solutions, the company has seen successful expansion into the global market for years now and is becoming one of the leading companies in numerous industries. Its solutions in the technologies of manual, automatic and robotic air blasting, shot peening, dry ice or dry snow cleaning, ultra-high-pressure water jetting, as well as fully automated enameling solutions, are being used in the most technology-intensive industries – from aviation, automotive, metalworking, foundry and casting, energy to medical implant and pharmaceutical industries. In 2020 the company launched its new Addiblast™ brand, which covers the processing and cleaning of the most demanding products in the area of advanced 3D technology. This year it plans to register an independent line of machines designed for the surface treatment of medical implants. With its many years of experience, exceptional breadth and depth of knowledge, unwavering passion for research, and responsible attitude to work, the company provides its customers with state-of-the-art equipment and cutting-edge solutions to help them accomplish their goals. 

One such solution is the ROBOBLAST 35-25 robotic blasting chamber, designed by FerroECOBlast® Europe for the family-owned and production-oriented company Vrata Deržič s.p. from Dobova, Slovenia, which has been present in the global market for as many as 25 years now with its most reliable fire doors that enhance the safety of lives and raise the bar in construction standards. In addition to hinged and sliding fire doors, they also manufacture security doors for residential buildings and door frames in various designs. Their automatic sliding fire doors with X-ray protection and fanlight fire doors are installed at the Celje Emergency Medical Centre and at the Faculty of Medicine in Maribor, respectively. They strive for continuous development and progress in order to ensure the highest quality of their products, which they achieve through ongoing optimization of production processes. Their latest additions are CNC bending machines, which lend beautiful, straight lines to their products, an optical laser with an automatic rack for the loading and unloading of sheet metal, and a FerroECOBlast® Europe automatic robotic blasting chamber, which provides their products with the highest level of coating adhesion – this has allowed them to enter new markets where weather conditions are particularly challenging.


Before acquiring the ROBOBLAST 35-25 automated blasting machine, Vrata Deržič sanded their products by hand and therefore was unable to meet the required standards for coating adhesion, which is an essential consideration for their customers living in extreme weather conditions with temperatures ranging from –40°C to +40°C, in humid regions, aboard ships or in desert environments. To enter the latter market as well, the company was looking for an automated solution that provides full control over sandblasting, delivers gentle roughness without damaging the galvanized surface, reaches all angles and corners, and ensures the best possible level of coating adhesion. The required throughput was 40 door panels and frames with a uniform roughness profile produced over a time span of eight hours.

To address their needs, the company FerroECOBlast® Europe, from Dolenjske Toplice, Slovenia, designed the ROBOBLAST 35-25 Automatic Chamber, which allows for the simultaneous uniform and controlled sandblasting of up to three door panels of different sizes, up to the maximum dimensions of 3200x2500x250 mm. Before starting the machine, the user simply loads the door panels into the rotation unit in front of the blasting chamber and then selects the desired type, or enters the dimensions, of the workpieces on the touch screen. The rotation unit lifts the workpieces one by one and then rotates them so that they are aligned with the conveyor before carrying them into the chamber. For optimal reach and coverage of angles, the sandblasting is performed using two blasting nozzles. After the sandblasting process has completed, the robot cleans them with compressed air, automatically repeats the blasting process on the opposite side and then returns them to the initial position. From there, the user offloads them onto a suspension conveyor and moves them into the powder coating chamber while loading the next pair of door panels into the rotation unit.

The machine design currently features a rotation unit and a robot with two nozzles, but it can also be upgraded with an additional robot installed in a dedicated location at the front, which would eliminate the need for rotating in the event of increased quantities and would allow the surface treatment of the entire workpiece from both sides to be carried out in a single cycle. The machine is equipped with a CENTRO 4/6 ECO 700 filtering and recycling system, which allows the abrasive used to be transported from the blasting chamber through the separator, where dust is removed, and then returned into the sandblasting system. The dust is collected in a dust container inside the filtering system, and the cleaned abrasive is returned to the sandblasting generator for reuse. Such a system means low consumption of abrasive medium and 100% process repeatability, and the TZP-600-type sandblasting generator with automatic refilling allows for the sandblasting process to run without interruptions.


The flawless surface preparation ensures proper adhesion of coatings to galvanized panels, regardless of whether a wet or dry powder coating is to be applied. FerroECOBlast® Europe sandblasting solutions are excellent substitutes for ecologically unsustainable chemical surface pretreatment processes and effectively replace manual sanding and roughening, delivering superior quality in accordance with the most stringent standards across various industries.