Why your Filament Winding Design might be Stronger but not Smarter
In filament winding, maximizing strength is often the primary design goal. After all, fiber-reinforced composites are widely valued for their high strength-to-weight ratio. However, focusing solely on strength can sometimes lead to overengineered or inefficient designs.
This article explores why stronger isn't always better, and how incorporating smarter design strategies can lead to better-performing, more cost-effective composite products.
More fibers, more problems?
Adding more fiber layers or increasing thickness may improve burst pressure or stiffness, but it can also introduce drawbacks:
Increased material usage and part weight
Longer winding cycles and higher production costs
Reduced flexibility (especially in hoses or curved parts)
Challenges in processing, such as wrinkling or uneven build-up
Instead of relying on additional layers, smarter designs focus on efficient fiber placement that matches that load conditions and functional requirements of the load conditions and funtional requirements of the product.
2. Understanding load paths and stress distribution
Composites behave differently than metals. Their strength depends on how fibers are aligned with the load. Designing with this in mind requires:
Identifying the primary loads (axial, hoop, torsional, etc,)
Selecting suitable winding angles to support those loads
Avoiding stress concentrations in transitions and end domes
Modern filament winding software often includes tools to simulate these factors, helping engineers balance performance and efficiency.
3. Smarter design means holistic thinking
A smart winding design considers not just structural strength, but also:
Manufacturability: Is the fiber path achievable on the available equipment?
Material usage: Can the same performance be reached with less fiber?
Product function: Are flexibility, weight, or fatigue life critical?
Cost: Are winding times and material costs optimized?
By addressing these considerations early in the design process, engineers can reduce rework, minimize trial-and-error, and streamline production.
4. Examples of Optimized vs. Overengineered designs
Consider the case of a pressure vessel where the helical layers are unnecessarily thick. The resulting product may pass testing, but:
It uses more fiber than needed
It adds extra weight
It increases machine time
In contrast, an optimized design may use fewer layers—but aligned more precisely with the stress distribution—achieving the same or better performance with reduced resource consumption.
Conclusion:
Strength will always be an essential design target in filament winding. But smart design goes beyond just strength—it considers efficiency, functionality, manufacturability, and cost. By taking a more holistic approach, engineers can unlock better performance and more sustainable use of materials.