Technical cover balls: evaporation protection and energy efficiency

Technical cover spheres (also known as floating spheres ) are a simple yet highly effective solution for open process baths and tanks. The hollow spheres, made of HDPE or PVDF, float on the liquid in a self-organizing manner, forming a dense layer and achieving a surface coverage of approximately 91% . This reduces evaporation (by up to ~90%), stabilizes temperatures, and lowers emissions – all without moving parts and requiring no maintenance . For engineers and plant managers, this translates to measurable evaporation protection , increased energy efficiency , and greater process stability.

How do technical cover balls work?

The system works based on physics rather than mechanics: Many hollow plastic spheres are placed on the liquid surface. Due to their density and geometry, they arrange themselves into a tightly packed pattern – the remaining spaces ensure minimal gas exchange and flexibly accommodate movements or temperature changes.

• ~91% coverage: The tightly packed bead bed significantly reduces the free surface area.

• Dynamic adjustment: The cover remains in place even with fluctuations in fill level , installed components or agitators – no opening or repositioning is necessary.

• Thermal effect: The air trapped inside the spheres acts as insulation ; heat losses at the surface are noticeably reduced.

Concrete benefits for operations and the environment

• Evaporation protection : The direct air-liquid interface shrinks massively – this reduces the evaporation rate by up to ~90% and reduces refill quantities.

• Energy efficiency: The insulating air space inside the hollow spheres reduces heat loss at the surface. Processes maintain more constant target temperatures, thus reducing heating requirements.

• Emissions control: Significantly fewer chemical fumes and odors are released. This improves occupational safety, the environmental footprint, and acceptance by local residents.

• Process stability: Reduced surface losses and lower external influences keep concentrations stable – re-dosing can be reduced.

• Maintenance-free: No hinges, covers or sliders, no manual handling. The Floating Spheres operate passively and reliably – even under changing conditions.

Material selection: HDPE vs. PVDF – clear recommendations

HDPE – the lightweight all-rounder

• Properties: Density approx. 0,96 g/cm³ , temperature stable up to ~80 °C , very good resistance to many acids, alkalis and solvents.

• Recommended use:

  • Electroplating baths with moderate temperatures

  • Wastewater treatment , equalization and buffer basins

  • Open pools/koi ponds and technical storage facilities

• Advantages: High buoyancy, economical, versatile.

PVDF – the high-end material for aggressive media

• Properties: Density approx. 1,78 g/cm³ , temperature stable up to ~150 °C , very high chemical resistance to strong acids, chlorides and solvent vapors.

• Recommended use:

  • Anodizing and electroplating processes with aggressive media

  • Pharmaceuticals and processes with high vapor loads

• Note: Higher material cost, but robust and reliable in extreme environments in the long term.

Applications with measurable added value

Electroplating

Uniform coating thicknesses require stable bath temperatures and clean surfaces. Technical cover spheres reduce heat loss , minimize oxidation on the bath surface, and thus reduce energy consumption and defects . The result: more consistent coating quality and lower operating costs.

Anodizing technology

Sensitive alloys (e.g., EN AW 2024) benefit from stable electrolyte chemistry . PVDF floating spheres keep aggressive vapors away from the environment and reduce moisture ingress from the atmosphere – this supports a homogeneous oxide layer and reliable process windows.

Water/Wastewater

Open pools lose significant amounts of water and energy through evaporation . HDPE cover spheres significantly reduce evaporation, minimize odors , and inhibit algae growth . Seasonal effects (e.g., frost ) are mitigated, and resource consumption decreases.

Sustainability & Economic Efficiency

• Saving water: Less evaporation means smaller amounts of dessert.

• Saving energy: Lower heat emission reduces heating requirements and CO₂ footprint.

• Saving on chemicals: More stable concentrations mean less re-dosing.

• Easily scalable: From small bathrooms to large pools – the solution grows with you, without any structural changes.

Next step: Technical check with Euro‑Matic

You want technical cover balls in your company or optimize existing tanks? Euro‑Matic supports you in material selection, sizing and Amortization estimate.
Act now: Book a consultation now or retrieve product information: Contact

FAQ – Technical Cover Balls

1) How do cover spheres achieve ~91% surface coverage?
The balls arrange themselves self-organizing in a dense pattern and cover around 91% the surface. Small gaps ensure gas exchange and freedom of movement of the medium.

2) What causes evaporation to decrease by up to ~90%?
The greatly reduced free surface minimizes direct air contact, resulting in significantly fewer molecules escaping – the Evaporation rate fällt by up to ~90% (reported).

3) Which material is suitable for my process – HDPE or PVDF?
HDPE: moderate temperature range, high buoyancy, economical. PVDF: height Temperature and chemical resistance For aggressive media or steam exposure. We advise based on the medium, temperature, and environment.

4) Do Floating Spheres also work with agitators or changing fill levels?
Yes. The ball bed adapts dynamically Even with Stirring movements and Level changes the coverage remains largely intact.

5) How much maintenance is required?
The systems are passive and maintenance-freeThere are no hinges or mechanics. Visual inspections and occasional cleaning of the surface are sufficient in practice.

Technical cover balls: evaporation protection and energy efficiency

Technical cover spheres (also known as floating spheres ) are a simple yet highly effective solution for open process baths and tanks. The hollow spheres, made of HDPE or PVDF, float on the liquid in a self-organizing manner, forming a dense layer and achieving a surface coverage of approximately 91%. This reduces evaporation (by up to ~90%), stabilizes temperatures, and lowers emissions – all without moving parts and requiring no maintenance. For engineers and plant managers, this translates to measurable evaporation protection, increased energy efficiency, and greater process stability.

How do technical cover balls work?

The mechanism is based on physics rather than mechanics: Numerous hollow plastic spheres are placed on the surface of the liquid. Due to their density and geometry, they self-assemble into a tightly packed pattern – the remaining spaces ensure minimal gas exchange and flexibly accommodate movement or temperature changes.

• ~91% coverage: The tightly packed sphere bed significantly reduces the free surface area.
• Dynamic adjustment: In the event of fluctuations in the fill level, installation parts or agitators, the cover remains intact – no opening or repositioning is necessary.
• Thermal effect: The air enclosed in the spheres acts as an insulator; heat loss at the surface is noticeably reduced.

Concrete benefits for operations and the environment

• Evaporation protection: The direct air-liquid interface shrinks massively – this reduces the evaporation rate by up to ~90% and reduces the amount of refilling required.
• Energy efficiency: The insulating air space within the hollow spheres reduces heat loss at the surface. Processes maintain target temperatures more consistently, and heating requirements are reduced.
• Emissions control: Chemical vapors and odors are significantly reduced. This improves occupational safety, environmental performance, and acceptance among residents.
• Process stability: Less surface losses and fewer external influences keep concentrations stable – re-dosing can be reduced.
• Maintenance-free: No hinges, covers, or sliders, no manual handling. The Floating Spheres operate passively and reliably – even under changing conditions.

Material selection: HDPE vs. PVDF – clear recommendations

HDPE – the lightweight all-rounder

• Properties: Density approx. 0,96 g/cm³, temperature stable up to ~80 °C, very good resistance to many acids, alkalis and solvents.
• Recommended use:
  • Electroplating baths with moderate temperatures
  • Wastewater treatment, balancing and buffer basins
  • Open pools/koi ponds and technical storage
• Advantage: High buoyancy, economical, versatile.

PVDF – the high-end material for aggressive media

• Properties: Density approx. 1,78 g/cm³, temperature stable up to ~150 °C, very high chemical resistance to strong acids, chlorides and solvent vapors.
• Recommended use:
  • Anodizing and electroplating processes with aggressive media
  • Pharmaceuticals and processes with high steam loads
• Note: Higher material price, but long-term robustness and process reliability in extreme environments.

Applications with measurable added value

Electroplating

Uniform coating thicknesses require stable bath temperatures and clean surfaces. Technical cover balls reduce heat loss and oxidation on the bath surface, thus minimizing energy consumption and defects. The result: more consistent coating quality and lower operating costs.

Anodizing technology

Sensitive alloys (e.g., EN AW 2024) benefit from stable electrolyte chemistry. PVDF Floating Spheres keep aggressive vapors away from the surrounding environment and reduce moisture ingress from the atmosphere, supporting a homogeneous oxide layer and reliable process windows.

Water/Wastewater

Open pools lose significant amounts of water and energy through evaporation. HDPE cover balls significantly reduce evaporation, reduce odors, and inhibit algae growth. Seasonal effects (e.g., frost) are mitigated, and resource consumption is reduced.

Sustainability & Economic Efficiency

• Save water: Less evaporation means less refilling.
• Save energy: Lower heat output reduces heating requirements and the CO₂ footprint.
• Save chemicals: More stable concentrations mean less re-dosing.
• Easily scalable: From small pools to large pools – the solution grows with you, without any structural changes.

Next step: Technical check with Euro‑Matic

Would you like to use technical cover balls in your facility or optimize existing pools? Euro‑Matic supports you with material selection, dimensioning, and amortization estimates.
Act now: Book a consultation now or get product information: {{LINK_PRODUCT}}.

FAQ – Technical Cover Balls

1) How do cover spheres achieve ~91% surface coverage?
The spheres self-organize in a dense pattern, covering approximately 91% of the surface. Small interstices ensure gas exchange and freedom of movement of the medium.

2) What causes evaporation to decrease by up to ~90%?
The significantly reduced free surface minimizes direct air contact. This results in significantly fewer molecules escaping, reducing the evaporation rate by up to ~90% (data-based).

3) Which material is suitable for my process – HDPE or PVDF?
HDPE: moderate temperature range, high buoyancy, economical. PVDF: high temperature and chemical resistance for aggressive media or steam exposure. We advise based on the medium, temperature, and environment.

4) Do Floating Spheres also work with agitators or changing fill levels?
Yes. The ball bed adapts dynamically. Even with stirring movements and fill level changes, the coverage remains largely intact.

5) How much maintenance is required?
The systems are passive and maintenance-free. There are no hinges or mechanical components. Visual inspections and occasional surface cleaning are sufficient in practice.