Vertical Coating Lines for Aluminum Profiles

An automated line with a continuously moving conveyor for mass painting of aluminum profiles up to 8 meters long. Vertical coating ensures high productivity: from 200 to 1.000 profiles per hour.

Vertical painting lines are designed for applying polymer coatings to aluminum profiles for outdoor use in architectural construction.

The lines include a full technological processing cycle with special surface preparation for products with a long service life. It is the surface preparation that determines the quality of the final polymer coating for successful passage of the multi-stage certification process.

EUROIMPIANTI equipment complies with the strict quality requirements and standards of international certification bodies QUALICOAT and AAMA for the production of architectural aluminum profiles.

The presence of the QUALICOAT SEASIDE quality mark indicates a higher level of corrosion resistance of the coating when used in aggressive marine climates. The service life of building structures is at least 50 years under the influence of atmospheric precipitation, ultraviolet radiation, and temperature changes.

 

EUROVERTICAL Aluminum Profile Coating Lines

 

Compliance with international quality standards for the products opens up new markets for manufacturers and provides significant competitive advantage due to the aesthetics and functional durability of the polymer coating.

Model SPEED-UP

Productivity growth potential. Vertical lines of Speed-Up model have a unique capability to increase productivity by two times without increasing the occupied space.

The Speed-Up model allows starting with a productivity of X and doubling it to 2X over time. The upgrade can be completed in just 48 hours. As a result, the length of all active zones increases, and the conveyor speed doubles.

Upgrade cost. The lines are initially designed to meet the customer's current needs, while the structure provides the possibility of upgrading the equipment in the future. For example, if the original line has a conveyor speed of 0,75 m/min, it can be increased at any time to 1,5 m/min. Productivity will increase by 100 %, and the cost of such modernization will be about 15 - 20 % of the initial investment.

The equipment of the line includes a complete technological cycle of painting aluminum profiles, in accordance with the requirements for architectural building elements:

Surface Preparation of Aluminum

This is an important technological stage, the quality of which determines the compliance of the final coating with the strict requirements of the QUALICOAT standard.

Tunnel of pre-treatment of the surface is designed specifically for aluminum profiles. It uses a combined spray-cascade method. The mechanical processing of the spray nozzles and "waterfall" pouring is carried out at low pressure. The advantages of a combined washing include:

• provides uniform intensity and evenness of surface treatment throughout the length of the profiles;
• has significantly fewer nozzles that need to be periodically cleaned;
• saves electricity on the transfer and spraying of working fluids.

For aluminum, a special cycle of chemical treatment is used, which includes mandatory etching and chromate passivation stages. Responsible companies that understand the importance of sustainable development use environmentally friendly chromate-free passivation.

Minimum 6-stage cycle for aluminum, ensuring corrosion resistance in salt spray for more than 1.000 hours:

1. Acid degreasing;
2. Acid etching;
3. Technical water rinse;
4. Demi water rinse;
5. Chromate-free passivation;
6. Final demi water rinse.

To achieve higher coating durability and comply with SEASIDE standards (over 1.500 hours), 7 - 9 stage cycles with chromate passivation and additional rinsing stages are used. A greater number of intermediate rinses ensure higher quality of the conversion layer and savings on chemical reagents. More details on surface preparation cycles.

Coating of aluminum profiles must be carried out with mandatory surface preparation. Without proper etching and application of a conversion layer, the coating will not last long. Such products will not pass QUALICOAT certification testing successfully.

Additional options. The equipment of the tunnels includes systems for monitoring the solution parameters and automatic dosing of reagents. This significantly simplifies the process, improves safety, and reduces the consumption of chemical concentrates.

Drying of Profiles After Washing

After washing and applying the conversion layer, the profiles are placed in a drying oven with enhanced air circulation, heated to a temperature of 110 - 120 °C.

Intensive forced ventilation ensures even temperature distribution in the working volume of the oven and allows for quick drying of the surface while preserving the conversion layer.

Utilization of heat from hot profiles. Thanks to the combination of ovens in the drying process, the heat from the cooling profiles is utilized after the polymerization stage. After the polymerization oven, the hot profiles, heated to 180 - 190 °C, pass through the drying oven in a counterflow, giving off some of their heat for the drying stage. This solution allows for the rational use of the heat from the cooling profiles to achieve maximum energy efficiency of the technology.

Painting Aluminum Profiles

After drying and cooling, the profiles are transported to the painting booth. In the vertical lines, the application of powder coating is fully automated. Only one operator is required to manage the process and change colors.

Painting booth DIAMOND. The new patented spray booth EUROIMPIANTI model DIAMOND has a rhomboid shape reminiscent of a cut diamond. The walls and floor of the booth are made up of rotating dielectric plastic belts, which are rotated using a belt drive system. The walls of the booth are continuously cleaned of powder, which is sucked into the recovery system for reuse in the painting process.

Double recovery system fully restores the paint and prevents powder emission into the workshop. Each of the two parallel 3-stage recovery systems includes a highly efficient cyclone, a self-cleaning cartridge filter module, and an absolute air filtration unit.

Thanks to the continuous self-cleaning of the booth and the double parallel recovery system, the color changeover time takes only 5 minutes. The booth is specifically designed for frequent color changes and allows for painting dozens of small batches in different colors during a single shift.

Fast color change allows for a reduction in equipment purchasing costs and the use of only one booth instead of two, as is traditionally required for frequent color changes.

The automatic spraying group is installed on two opposite sides facing each other. The spray guns are positioned at the necessary angles to fully cover the surface of profiles of any shape and complexity of section, eliminating the need to rotate the profiles during paint application.

Possibility of one-sided painting. The absence of rotation and the opposite positioning of manipulators allows for painting profiles only on one side, if necessary. For example, when combining different materials of internal and external finishing of windows and doors.

Contour of optical sensors at the entrance to the cabin with a step of 250 mm controls the movement of the manipulators, depending on the length of the incoming profiles.

Powder center is designed to minimize color changeover time. Built-in intelligent functions take into account downtime during color changes and the paint program for each color. The smart powder center controls the actual powder consumption for each batch of products.

Digitalization of the process helps to keep track of the cost of production for each customer. The automatic system also takes into account the working life of consumable parts and warns in advance of the need for maintenance.

Clean room. The paint application zone is surrounded by polypropylene panels to protect against external air flows. Protection against drafts ensures an even layer of powder of optimal thickness and cleanliness of the production room.

Polymerization of Paint in the Oven

The final coating is formed in the oven. The heating temperature of the profiles and the duration of the thermal treatment should correspond to the recommendations specified in the technical specifications of the paint manufacturer. Typically, the polymerization of thermosetting powder coating occurs within 15 - 20 minutes at a temperature of 180 - 200 °C.

Completeness of polymerization. The length of the path that profiles travel inside the oven is designed depending on the working speed of the conveyor to ensure the maximum required processing time at a given temperature.

Energy saving ovens. To fully utilize the heat, the polymerization oven is combined with a drying oven. After the polymerization stage, before leaving the oven, the profiles pass through a drying oven where they transfer some of the heat to the drying parts after surface preparation.

Combined drying and curing ovens with rational use of the heat from cooling profiles allow for reducing energy consumption and increasing energy efficiency of the technological cycle.

Uniform temperature in ovens. Thanks to enhanced ventilation and multi-level placement of heat exchangers, the ovens maintain a stable temperature with even heat distribution along the entire height of the profiles.

Transportation of Profiles

Profiles are transported on a continuously moving conveyor, sequentially passing through all stages of the powder coating technological cycle.

Vertical loading minimizes the spacing between the profiles loaded onto the conveyor. Depending on the dimensions of the profile section, the distance between the hangers ranges from 100 to 200 mm. Depending on the weight of the profiles, the conveyor can have a load capacity ranging from 80 to 250 kg/m.

Easy loading and unloading. The monorail overhead conveyor is equipped with special translators for transferring profiles from a horizontal position to a vertical position during loading, and vice versa — from a vertical to a horizontal position during unloading of painted profiles. The speed of the lifting/lowering devices is synchronized with the conveyor speed. A packaging line can be integrated into the unloading table for painted profiles.

Cleaning Hooks from Baked-on Paint

Stable grounding of profiles. In powder coating technology, it is important to keep the hanging hooks in an ideally clean state. Good contact between the hook and the profile is necessary for electrical grounding. The better the conductivity, the higher the powder transfer efficiency. And this means a more uniform and thinner layer of applied powder coating.

Chemical cleanup. To clean hooks from baked-on paint, a chemical ultrasonic cleaning station is integrated into the conveyor line. An immersion tank with a special chemical solution is installed in the line between the profile unloading and loading zones.

Cleaning cycle for hooks. Immediately after removing the painted profiles, the conveyor passes over a tank where the lower parts of the hooks are dipped. It takes less than 3 minutes to clean them from the polymerized paint. After cleaning, the restored hooks are ready for subsequent hanging of profiles and passing through a new painting cycle.

 

Competitive Advantages of EUROVERTICAL

• Reasonable price. Thanks to the modularity and standardization of components, EUROIMPIANTI's vertical lines have the best price / quality ratio. Structural flexibility allows for the design of customized lines with quick assembly / disassembly using only bolted connections.
• Maximum energy efficiency of "hot" technological stages. From the insulation of the surface preparation tunnel to the rational use of heat from cooling profiles in combined drying and polymerization ovens.
• High productivity. Thanks to the vertical hanging and the flexibility of production in using different colors, the delivery times of finished products are reduced. The equipment is designed for intensive use 24 hours a day.
• Opportunity to increase productivity. The Speed-Up model design allows for a doubling of productivity without increasing the floor space. Forward-looking design takes into account business scaling prospects in the future.
• Fast color change. Thanks to the innovative DIAMOND paint booth with a self-cleaning system of rotating plastic walls and floor. Continuous cleaning of the chamber significantly simplifies and speeds up the color change process. The transition from color to color is made by one operator in just 5 minutes.
• Low investment. Fast color change reduces the gaps on the conveyor between batches of different colors. This increases the flexibility of production and eliminates the need for investment in a second spray booth.
• Possibility for one-sided painting. The opposite positioning of spray guns and the absence of rotation allows for one-sided painting of profiles. This makes it possible to use combined materials for the internal and external finishing of finished products.
• Continuous cleaning of hooks for better grounding of profiles. This extends the service life of hooks and ensures consistently high coating quality with optimal powder consumption.
• Simplicity of use and maintenance. Only 5 workers per shift are required to operate the vertical line. Thanks to high automation and protection against the "human factor", even low-skilled workers can be quickly trained.
• Compliance with QUALICOAT standards. Only by using certified coating lines, chemical agents, and paint, it is possible to successfully pass dozens of tests and obtain an international quality mark. This will increase the competitiveness of painted products and open up global markets.

The main competitive advantage is the minimum cost of painting a unit of production, due to the efficiency of the equipment, high working life and low operating costs.