Disc Refiner Blade Segment Curved Edges
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional disc refiner blade segments experience discontinuities at interfaces, leading to disturbances in refining and material flow, and require precise tolerances to prevent unrefined pulp escape, which complicates manufacturing and operation.
Innovation Solution
The blade segment features curved side edges with a single radius of curvature, where the first side edge is concave and the second side edge is convex, allowing for continuous refining surface portions that enhance material flow and structural integrity, enabling easier alignment and manufacturing with larger tolerances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If straight side edges are used in conventional blade segments, then manufacturing is simpler, but discontinuities occur at interfaces causing disturbances in refining and material flow
Solution Approach 1:
The blade segment side edges are designed with curved profiles instead of straight lines. The first side edge features a concave curvature while the second side edge has a convex curvature, creating overlapping refining surfaces at the interfaces between adjacent blade segments. This curvature eliminates the discontinuities and gaps that occur with straight edges, ensuring continuous refining action and smooth material flow across segment boundaries.
2Reliability
If precise tolerances are enforced at blade segment interfaces, then unrefined pulp escape is prevented, but manufacturing complexity and difficulty increase
Solution Approach 1:
The curved side edge profiles with concave and convex curvatures create overlapping refining surfaces that are inherently more tolerant to manufacturing variations. The overlapping geometry ensures that even with larger tolerance ranges, the refining surfaces maintain continuous contact and proper alignment, preventing unrefined pulp escape without requiring extremely tight manufacturing tolerances.
Solution Approach 2:
By changing the geometric parameters of the side edges from straight to curved profiles, the invention fundamentally alters the interface geometry. This parameter change transforms the tolerance sensitivity from critical to acceptable, allowing standard manufacturing tolerances to produce reliable interfaces that prevent pulp escape while maintaining refining continuity.
3Reliability
If blade segments are designed with curved side edges, then refining performance and structural strength improve, but manufacturing complexity increases
Solution Approach 1:
While the side edges are curved, the curvature follows simple geometric patterns (concave and convex arcs) that can be efficiently manufactured using standard CNC machining or molding processes. The curved profiles integrate seamlessly with the blade bar and blade groove structures, creating a unified geometry that enhances structural strength without requiring complex multi-component assemblies or specialized manufacturing equipment.
Data Source
Figure 1~2
Figure 3~4
AI summary
A blade segment 1 of a disc refiner intended for refining fibrous material is provided, which blade segment 1 comprises an inner circumference 3 and an outer circumference 4 as well as a first side edge 5 and a second side edge 6 which combine the inner circumference 3 and the outer circumference 4. The first side edge 5 and the second side edge 6 of the blade segment 1 are curved so that one side edge is concave and the other side edge is convex. The first side edge 5 and the second side edge 6 of the blade segment 1 curve in the vicinity of the inner circumference 3 to the pulp-carrying direction, i.e. to the pumping direction, and in the vicinity of the outer circumference 4 to the pulp-holding direction, i.e. to the non-pumping direction.