At Polem, we have been using high-quality composite materials since 1972 to create storage products that are seamless, strong, and mirror-smooth. In this blog, we dive deeper into the differences between composite and other materials for silos and tanks.
What is composite?
Composite is essentially a compound material consisting of two or more components with different physical or chemical properties. When these components are combined, a new material emerges with properties superior to those of the individual constituents.
For Polem's silos and tanks, we use glass fiber reinforced plastic (GFRP), a specific type of composite. GFRP consists of:
- A polymer matrix (often polyester or epoxy resin)
- Reinforcement through glass fibers
This results in a material that combines the flexibility and design freedom of plastic with the structural strength of glass fibers.
Composite versus other materials
GFRP (Glass Fiber Reinforced Plastic)
GFRP is a specific type of composite. The term 'composite' is broader and can include other reinforcement materials, such as carbon fibers or aramid. At Polem, we use GFRP because of its excellent combination of strength, durability, and cost-effectiveness.
Polyester
Polyester is often the resin matrix used in GFRP. It is therefore a component of the composite, not the composite itself. It serves as a binder for the glass fibers and provides chemical resistance.
PP (Polypropylene) and PE (Polyethylene)
These are thermoplastic polymers used without reinforcement for various applications. They are more flexible than composite but lack the structural strength and durability provided by glass fiber reinforcement.
Steel and aluminum
Traditionally, silos and tanks are often made of steel or aluminum. Although these materials are strong, they have significant disadvantages compared to composite:
- They are more susceptible to corrosion
- They have poorer thermal insulation
- They require welds and joints that can weaken
- They have a rougher surface leading to more product adhesion
The advantages of composite for silos and tanks
1. Seamless construction
Our composite silos and tanks are manufactured in one piece, without seams or welds that can leak or weaken. This results in hygienic storage where no product can accumulate in crevices or corners.
2. Exceptional strength
Despite their relatively light weight, our composite structures are exceptionally strong and can safely store large quantities of material, even under demanding conditions.
3. Mirror-smooth finish
The interior of our silos and tanks is mirror-smooth, which ensures:
- Better product flow
- Minimal product adhesion
- Easier cleaning
- Improved hygiene
4. Corrosion resistance
Unlike metal alternatives, composite is virtually immune to corrosion, which significantly extends lifespan and reduces maintenance costs.
5. Thermal insulation
Composite naturally has excellent insulating properties. The insulation value of a tank or silo with 50 mm PU foam is comparable to that of a metal tank insulated with 100 mm rock wool and aluminum plating.
6. Low maintenance
Due to its durability and resistance to both mechanical and chemical influences, composite products require less maintenance than conventional alternatives.
Practical example
In the food industry, hygiene is crucial. The seamless finish of composite silos prevents product buildup in corners and crevices, which can cause mold formation and bacterial growth. Additionally, the mirror-smooth interior wall is ideal for products that are difficult to flow, such as powders and granulates that stick to rough surfaces.
A customer in the dairy industry noticed a significant improvement in product flow and a reduction in cleaning time after switching from steel silos to composite. Additionally, the thermal insulation proved to be much better, leading to less condensation and better product quality.
In the industrial sector, where many chemicals are used, the corrosion resistance of composite proves its value. While steel tanks regularly need maintenance or replacement due to degradation, composite tanks remain in perfect condition for years.
Finally
The choice of the right material for your silos and tanks directly influences the quality of your processes and end products. Composite offers clear advantages over traditional materials such as steel, aluminum, and unreinforced plastics.
Every grain, every drop. Quality in, quality out.
