Metric Fibre Number Claims and the Test Method behind Them
Metric fibre number claims require ISO 2370 gravimetric verification because airflow instruments skew up to fifteen percent across retting types and moisture regains.
Double Comb Clamp
Mechanical Tension
Pressure applied to flax bundles during the preparatory drafting phase maintains fiber alignment within the drawing frame. A double comb clamp restricts vertical movement of the raw material to ensure uniform delivery speed toward the rollers. These mechanisms prevent uneven stretching that results in thick or thin spots within the sliver.
Correct positioning stops individual filaments from sliding prematurely under the force of the machine cylinders.
Drafting Control
Tension settings determine the stability of the mass as it transitions between different mechanical stations. The double comb clamp exerts constant force across the breadth of the bundle to counter internal friction. Operators set the grip based on the specific moisture content and diameter of the flax stalks currently being processed.
Adjustments to the clamping pressure regulate how fibers transfer from the feeding zone to the pinning field without breakage. This precision reduces the accumulation of waste material at the transition points.
Acceptance Parameter
Consistency in the final sliver density relies upon the rigid mechanical constraints provided by the gripping hardware. Production logs record the settings of the double comb clamp alongside the measured linear density of the output to verify conformance with technical specifications. A shift in the clamp width or pressure alters the structural uniformity of the yarn.
Constant monitoring of these mechanical variables produces predictable fiber distribution within the sliver. Stable pressure application remains the most effective method for reducing variability across production batches.