Dual Combination Binder Weft Yarns for Papermaking Fabric Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional forming fabrics in papermaking lack stability and effective interweaving, leading to poor support and permeability, which affects the quality of the paper web during the papermaking process.
Innovation Solution
A double-layer forming fabric with dual combination binder (DCB) weft yarns that interweave with both top and bottom warp yarns, creating a more stable and permeable surface by increasing the interweaving of warp and weft yarns and providing long weft floats for a continuous paper-side surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If binder weft yarns use long weft floats to provide continuous paper-side surface, then paper web formation surface continuity is improved, but interweaving effectiveness with warp yarns deteriorates
Solution Approach 1:
The binder weft yarn is segmented into two distinct functional portions: a first portion that floats over the top warp yarns to create continuous paper-side surface, and a second portion that interweaves with the bottom warp yarns to provide fabric stability. This segmentation allows each portion to fulfill its specific function without compromise.
Solution Approach 2:
The binder weft yarn operates in multiple vertical dimensions simultaneously - it floats over the top warp yarns in one dimension while interweaving with bottom warp yarns in another dimension. This multi-dimensional configuration resolves the contradiction by allowing long floats for surface continuity while maintaining interweaving effectiveness through the bottom layer interaction.
2Ease of manufacture
If forming fabric uses conventional weaving techniques, then manufacturing simplicity is maintained, but fabric stability and support effectiveness deteriorate
Solution Approach 1:
The binder weft yarn serves multiple functions simultaneously: it provides structural binding between top and bottom layers, creates continuous paper-side surface through long floats, and enhances fabric stability through effective interweaving with bottom warp yarns. This multi-functionality is achieved within a conventional weaving framework, maintaining ease of manufacture while improving performance.
3Device complexity
If forming fabric has reduced interweaving between warp and weft yarns, then manufacturing complexity is reduced, but permeability and moisture removal effectiveness deteriorate
Solution Approach 1:
Different portions of the fabric exhibit different interweaving characteristics tailored to local requirements. The binder weft yarn has long floats in the top layer for permeability and moisture removal, while simultaneously providing structural interweaving in the bottom layer for stability. This local differentiation optimizes both permeability and structural integrity without requiring complex overall weaving structures.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The increased interweaving and use of DCB weft yarns enhance the stability and permeability of the forming fabric, resulting in improved paper web formation and moisture removal, leading to higher quality paper production.
Implementation Method 1
dual combination binder (DCB) weft yarns that interweave with both top and bottom warp yarns
Implementation Method 2
The aqueous medium drains through mesh openings of the forming fabric, known as drainage holes, by gravity
Implementation Method 3
Pressure from the rollers removes additional moisture from the web
Implementation Method 4
the forming fabric provides a papermaking surface on the upper surface of its upper run which operates as a filter to separate the cellulosic fibers of the paper stock from the aqueous medium
Data Source
Figure 1~3
Figure 4
Figure 5
AI summary
A forming fabric for a papermaking machine that comprises a machine-side layer and a paper-side layer is disclosed. The machine-side layer includes bottom warp yarns and bottom weft yarns that weave with at least some of the bottom warp yarns. The paper-side layer includes top warp yarns and top weft yarns that weave with at least some of the top warp yarns to create a weave pattern in a repeating pattern area, and at least one of the top weft yarns includes a paper-side float in the repeating pattern area that passes over a number of consecutive top warp yarns. The forming fabric further comprises a set of dual combination binder weft yarns disposed adjacent a top weft yarn. At least one dual combination binder weft yarn of the set weaves with some of the bottom warp yarns and some of the top warp yarns. Each dual combination binder weft yarn of the set includes at least one float in the repeating pattern area that passes over at least one top warp yarn. The at least one float is disposed adjacent to a float of another dual combination binder weft yarn of the set. The at least one float and the adjacent float combine to form a long weft float that passes over the number of consecutive top warp yarns passed over by the paper-side float to match the weave pattern of the top weft yarns. The long weft float occurs at least once in each repeat of the dual combination binder weft yarns.