Yarn Fineness
The indirect numbering system expresses yarn fineness as the length in meters per single gram of mass. Textile engineers utilize Nm metric count to specify yarn yield and drafting ratios across spinning and weaving operations. A higher numerical value indicates a finer spun yarn requiring higher quality raw flax bundles.
System formulas convert easily to direct tex values by dividing one thousand by the metric count number.
Draft Calculation
Spinning frame draft gear settings dictate the mass attenuation of roving strands needed to achieve a target thread thickness. As wet spinning frames draw out heated roving, ring spindles insert mechanical twist to lock fibers into a coherent structure at the target thickness. Maintaining precise Nm metric count requires continuous monitoring of roving linear density and spindle draft speeds on the spinning floor.
Variations in ambient humidity alter moisture regain, shifting the actual yarn count away from target specifications. Technicians perform routine skein reindex weighings to calibrate ring frame gear positions and maintain yarn weight uniformity.
Fabric Specification
Yarn sales contracts define target count levels along with allowable tolerance ranges, typically set within plus or minus three percent of nominal values. Shipments falling outside specified count limits incur financial penalties or lot rejection by weaving mills. Quality control reports record average count and variation coefficient for every production lot.
