Calculating Wet Spinning Scrap Deductions for Mass Balance Ledger Verification
Verify wet spinning mass ledgers by adjusting raw inputs to standard moisture regain, deducting verified chemical bath extraction losses and weighed mechanical scrap.
Hot Water Extractables
Soluble Compound
Quantitative chemical analysis determines the weight percentage of water-soluble substances that can be removed from raw flax fibers when boiled in pure water. The percentage of hot water extractables consists of free sugars, pectins, and organic salts that reside on the surface and within the cell walls of the flax fiber bundle. These compounds are analyzed to evaluate the cleanliness of the flax after retting and before the spinning process.
The measurement is expressed as a weight loss percentage based on the dry mass of the fiber, providing a clear indication of how much material will be lost during yarn scouring.
Spinning Preparation
Spinning operations are affected by high concentrations of these soluble substances because they can gum up the drawing rollers and cause uneven drafting. When hot water extractables are high, the roving becomes stiff and sticky during the hot wet-spinning stage, which leads to frequent thread breaks. Spinning mills adjust the wash water temperature and detergent dose in the pre-treatment baths to remove these unwanted substances.
Washing Outcome
Linen quality certificates list the extractable content to guarantee the fabric will not experience excessive shrinkage. If the value exceeds the specified limit, the woven fabric may experience irregular hand feel. Ensuring low extractable levels ensures stable dye affinity.