Problem

Wall thickness is one of the most critical parameters in rotomolded water tanks, yet it is often misjudged. Incorrect thickness may lead to deformation, cracking or reduced lifespan, while excessive thickness increases cost and may create internal stress.

For tanks from 0.2T to 30T, wall thickness must be selected based on capacity, structure and application conditions rather than a fixed standard.

Why It Happens

Rotomolding relies on natural material distribution rather than pressure. Wall thickness affects strength, heat transfer and material flow.

As tank size increases, hydrostatic pressure increases. Larger molds also create longer material flow paths, increasing the risk of uneven thickness.

Environmental conditions such as UV exposure and temperature variation also influence thickness requirements.

Technical Insight

Structural strength depends on both wall thickness and geometry.

Flat wall designs require higher thickness, while reinforced or ribbed structures allow lower thickness with similar strength.

Optimized design focuses on structure rather than simply increasing thickness.

Recommended Thickness

0.2T–1T: 6–8mm
1T–5T: 8–10mm
5T–10T: 10–12mm
10T–30T: 12–15mm

Additional safety margin of 1–2mm may be used for chemical applications.

Process Impact

Increasing thickness increases heating time by 20%–40%
Cooling time also increases
Uneven cooling may cause internal stress

Balanced thickness design improves both quality and efficiency

Application-Based Adjustment

Agriculture focuses on cost and durability
Industrial use requires higher strength
Chemical storage requires higher safety margin

Thickness should match application conditions

Optimization Strategy

Use reinforcement instead of increasing full thickness
Strengthen bottom and connection areas
Maintain uniform thickness
Optimize material distribution

Conclusion

Ideal wall thickness is a balance between capacity, structure and process