Dew Retted Line Flax Hackling Yield Fundamentals and Testing
Dew retted line flax hackling yield determines long line fiber recovery, tow ratios, and yarn production costs through precise fineness and strength testing.
Comb Tow
Fibrous Residue
Graded flax waste resulting from hackling machinery forms the physical basis of comb tow, representing the short broken fibres pulled away during preparatory carding inside Chinese spinning mills. Mechanical lines separate long line flax from this tangled mass before the material enters draft frames for yarn preparation. Mill supervisors record the classification of the bundle within the daily bale yield sheet, distinguishing the byproduct from clean sliver.
Fibre grades apply strictly to these raw or semi cleaned strands based on residual woody shive content and staple length, whereas fabric grades measure woven density and tensile strength after spinning finishes.
Draft Tolerance
Processing limits restrict how much short material enters roving frames without causing uneven yarn diameter during wet spinning. Operators adjust roller settings when comb tow proportions exceed normal mill tolerances, preventing weak spots from forming in the final yarn. Buyer acceptance criteria demand specific cleanliness levels that often surpass internal mill standards, requiring additional cleaning cycles before export documentation receives final approval.
Export Ledger
Commercial documents accompany each maritime shipment of processed flax waste to foreign spinning operations, detailing moisture regain percentages alongside bale weights on the final bill of lading. Customs declarations list the commodity according to international harmonized system codes for textile fibres, separating cleaned flax waste from raw agricultural straw. Regulatory compliance depends on accurate weight verification at the export port, ensuring that moisture content remains below the maximum threshold allowed for ocean freight.
Line against Tow When the Offer Sheet Declares Neither
Specify long-staple line flax and wet spinning in purchase contracts to prevent spinners from substituting short tow fibre into ambiguous metric yarn orders.