Papermaking Mat with Aligned Fiber Bundles for Crack-Resistant Winding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The mat material used in exhaust gas conversion apparatuses is prone to cracking when wound around a base material due to differences in inner and outer circumferences during the winding process.
Innovation Solution
A papermaking mat with a rectangular shape, featuring inorganic fibers and raised portions aligned in one direction, is produced by flowing a slurry containing fiber bundles that are entangled and twisted, which are then wound around the base material in a direction perpendicular to their alignment, reducing stress and cracking likelihood.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the mat material is wound around the exhaust gas treatment unit to increase holding force, then the holding capability is improved, but the mat material is prone to cracking due to differences in inner and outer circumferences during winding
Solution Approach 1:
The mat material is segmented into multiple layers with different fiber orientations. The first layer has fibers oriented in the winding direction to resist circumferential stress, while the second layer has fibers oriented perpendicular to the winding direction to provide dimensional stability and prevent excessive expansion, thereby reducing cracking during winding
Solution Approach 2:
The mat material uses a composite structure combining two layers of nonwoven fabrics with different fiber orientations. This composite configuration allows the material to simultaneously provide high holding force through winding while maintaining crack resistance by distributing mechanical stresses across different fiber directions
2Force
If the mat material is made with high surface pressure to improve holding capability, then the holding force is improved, but the material becomes more rigid and prone to cracking during winding
Solution Approach 1:
The mat material is divided into multiple layers with different fiber orientations and properties. The first layer provides high surface pressure and holding force, while the second layer maintains flexibility and dimensional stability, allowing the material to adapt to winding without cracking
Solution Approach 2:
The mat material uses different fiber orientation parameters in different layers. The first layer has fibers oriented at 0 degrees to the winding direction for high holding force, while the second layer has fibers oriented at 90 degrees to maintain flexibility and prevent excessive expansion during winding, thus preventing cracks
Data Source
Figure 1A~1B
Figure 1C
Figure 2A
AI summary
A papermaking mat that is less likely to be cracked even when being wound around a base material is provided. A papermaking mat of the present invention has a rectangular shape in a plan view and includes inorganic fibers, a first main surface, and a second main surface facing the first main surface. The first main surface includes multiple raised portions each having a linear shape. When the papermaking mat is viewed in a plan view, the raised portions: are aligned in one direction in a plane direction of the first main surface; have an average length of 5 to 200 mm, an average width of 1 to 50 mm, and an average height of 0.05 to 0.50 mm; amount to five or more in a range of a freely selected 10 cm-long × 10 cm-wide square of the first main surface; and include a fiber bundle being formed by entangling multiple fibers and twisting together.