Bituminous coatings are often used in the agricultural sector to protect infrastructure such as silos, tanks and other surfaces exposed to harsh weather conditions. This type of coating is prized for its robustness, waterproofing and ability to withstand chemicals. But what is a bituminous coating, and in what situations is it recommended? Here we explore the benefits and characteristics of this essential product for the agricultural world.
What is bituminous surfacing?
Bituminous coatings are composed mainly of bitumen, a black, viscous substance derived from petroleum. Bitumen has naturally impermeable properties, making it ideal for protecting various surfaces against moisture, corrosive chemicals and UV rays. These coatings are typically applied to metal, concrete or even wood surfaces, particularly in demanding environments such as farms, where infrastructure must withstand extreme conditions.
Advantages of bituminous surfacings
Bituminous pavements offer a multitude of advantages, particularly for agricultural applications:
- Exceptional impermeability: These coatings form a solid barrier against water, preventing seepage into silos and tanks, which is crucial for preserving crops and other stored materials.
- Chemical resistance: They are highly resistant to commonly used agricultural chemicals, such as fertilizers or pesticides, making them an ideal choice for protecting farm infrastructure.
- Durability: Once applied, bituminous pavements can last for many years without requiring major maintenance. It resists wear and tear due to temperature variations, weathering and mechanical aggression.
- Corrosion protection: This type of coating prevents metal corrosion, a common problem on farms where metal structures are exposed to damp environments and corrosive products.
Bituminous surfacing applications
1. Silo protection
Steel or concrete silos, used to store grain, fodder or even liquids, are exposed to constant humidity, which can lead to rusting or infiltration. Applying a bituminous coating to the exterior and interior of these structures ensures their longevity and protects stored materials from water damage.
2. Tank sealing
Agricultural tanks, whether used for water, fertilizer or other liquids, require extra protection against corrosion and leaks. Bituminous coatings create a watertight layer, protecting the tank interior from aggressive chemicals and moisture.
3. Roof protection
On many farms, the roofs of sheds and storage buildings are often covered with metal or concrete materials. A bituminous coating can be applied to make the roof watertight, while providing protection against the elements, thus extending the life of the structure.
How to apply a bituminous coating?
Applying a bituminous coating requires certain precautions to ensure optimum results. Here are the main steps to follow:
- Surface preparation: Make sure the surface to be coated is clean, dry and free from dust or grease. Any rust or impurities must be removed for the coating to adhere properly.
- Priming: Depending on the type of surface, a primer may be required to improve the adhesion of the bituminous coating.
- Coating application: Use an airless sprayer or roller to apply the coating evenly. Depending on the thickness required, several coats may be necessary.
- Drying time: Drying time depends on environmental conditions, but it is important to respect the time indicated by the manufacturer before exposing the surface to water or chemicals.
How to apply a bituminous coating with an airless sprayer?
Applying a bituminous coating with an airless machine is a fast, efficient way of covering large surfaces with uniform results. However, it requires adequate preparation, the right equipment and special precautions to ensure optimum results. Here are the steps to follow for a successful application:
1. Surface preparation
Before any application, it is crucial to prepare the surface properly. A poorly prepared surface can prevent the coating from adhering properly, leading to waterproofing or protection problems. Here are the steps to follow:
- Cleaning: Make sure the surface to be treated is clean, dry and free of dust, dirt, grease or residues. Use a wire brush to remove traces of rust if working on a metal surface. For concrete surfaces, high-pressure cleaning may be necessary.
- Repairing cracks and holes : If the surface has cracks or imperfections, these must be filled with a repair product before the bituminous coating is applied.
2. Choosing the right airless equipment
Not all airless sprayers are suitable for applying bituminous coatings, due to the high viscosity of these products. It is therefore important to choose a sprayer that can handle high-viscosity materials. Here’s what to consider:
- Sprayer type: be sure to use a high-pressure airless sprayer (often 250 to 345 bar) capable of handling heavy materials such as bitumen.
- Nozzle size: use a suitable nozzle, generally a nozzle size between 0.045″ and 0.055″ is recommended for this type of coating. This ensures good atomization of the material while providing effective coverage.
- Filtration: Bituminous coatings can contain particles that clog sprayer filters. Use large-mesh filters to avoid this problem, or sometimes no filters at all.
-
- Graco Dutymax GH300 DI – ProContractor
-
- Graco GH BIG RIG 833 ES – 16V260
3. Coating thinning (if necessary)
Depending on the type of bituminous coating you’re using, it may be necessary to dilute it before application. Always follow the manufacturer’s recommendations for dilution, as incorrect dilution can affect the quality of the coating.
- Ready-to-use product: If the product is ready-to-use, no dilution is necessary.
- Products to be diluted: Some products require the addition of specific solvents to reduce viscosity and facilitate spraying. Follow the recommended dilution proportions.
4. Application with airless sprayer
Application with an airless sprayer must be carried out with care to ensure even, long-lasting coverage. Here are the steps to follow:
- Test spray: Before starting application on the main surface, test the sprayer on a small area to check pressure, spray pattern and coating coverage.
- Coat application: It is recommended to apply the bituminous coating in several thin coats rather than one thick coat. This ensures better adhesion and more uniform drying. Allow each coat to dry before applying the next (refer to product drying time).
- Spray distance: Maintain an even distance of 30-60 cm between the airless nozzle and the surface to ensure even application.
- Constant movement: Move the sprayer evenly in horizontal and then vertical passes, overlapping sections slightly to avoid gaps.
Graco T-MAX 6912 (17X986)
5. Sprayer cleaning and maintenance
Once the application is complete, it is essential to clean your airless sprayer immediately to prevent the bitumen from hardening inside the pipes and nozzle. Use a solvent suitable for the product used (e.g. bitumen thinner) to clean the system.
- Nozzle removal: Remove the nozzle (and filters) for separate cleaning.
- Cleaning the tank: If you’ve been using a sprayer with a tank, be sure to clean it thoroughly by circulating solvent through it.
- General maintenance: Inspect seals and other sprayer parts for wear or leaks, and replace parts if necessary.
6. Safety precautions
Applying bituminous coatings presents certain risks, mainly due to the solvents contained in the product and the use of high-pressure machinery. Follow these safety tips:
- Personal protective equipment (PPE): Wear chemical-resistant gloves, goggles and a mask to prevent inhalation of solvent vapors.
- Ventilation: If working in an enclosed space (e.g. inside a silo), ensure good ventilation to prevent the build-up of toxic fumes.
- Temperature and weather conditions: Apply the coating in suitable weather conditions (no rain or excessive humidity) and respect the temperature ranges indicated by the manufacturer.
Applying a bituminous coating with an airless sprayer provides fast, even coverage, particularly suitable for large surfaces such as silos or roofs. With meticulous preparation, the right equipment and adherence to the application steps, you’ll achieve a long-lasting, high-quality result, guaranteeing optimum protection for your infrastructure. If you’d like to find out more about bituminous coating products or their application, don’t hesitate to contact our team of professionals and take a look at our other blog posts on the subject.
_________________________________________________
Love our content? You can find more here:
Check out our Airless Discounter YouTube channel
Airless Discounter Instagram account
Questions or queries?
For any further questions or if you would like to get your hands on one of these products seen in this article, you can contact us on +49 (0) 30 220 15436, fill out our contact form or email us. If you wish to purchase one of the products mentioned above, you can check them out in our online store. You can also visit us at our service base during office hours.
