Determining Flax Staple Profile Using Manual Comb Sorting
Manual comb sorting by ISO 2370 isolates technical flax bundle length profiles to prevent drafting waves, control short fibre content, and enforce purchase contracts.
Dual Comb Bed
Mechanical Assembly
Flax preparation machinery employs paired series of pinned bars to parallelize long bast fibres before spinning. Within this equipment, the dual comb bed consists of two opposing fields of needle-clad pins that penetrate the fibre bundle from both sides. This configuration ensures that the flax strand receives uniform drafting force and thorough separation of shives.
By holding the fibres securely between the two beds, the apparatus prevents uncontrolled slippage during the drawing process.
Combing Cycle
Pin bars within this assembly move in a rectangular path, rising into the fibre strand and travelling along its length before withdrawing. During the active phase of the cycle, the dual comb bed maintains a constant penetration depth to secure the flax bundle. This action holds the middle of the strand while the ends are combed.
Graduated pin densities on the consecutive bars of the mechanism gradually increase the degree of separation.
Processing Output
High-yield linen mills use this double-sided penetration to process heavy slivers without causing fibre breakage. Processing thick flax strands on single beds often leads to uncombed centres or surface tearing. The use of a dual comb bed eliminates these variations, allowing a drawing frame to run at higher linear speeds while maintaining a low coefficient of variation.
It is restricted to long flax line preparation because shorter tow fibres require different holding mechanisms. Consequently, mills using this setup report a more uniform draw, leading to fewer yarn breaks in the subsequent spinning stage and better efficiency across the weaving shed.