Mass Calculation
Laboratory analysis determines the theoretical mass of a wool or cotton lot once all non-cellulosic or non-keratinous impurities are removed. Calculating the clean dry weight involves subtracting the mass of grease, vegetable matter, dust and residual moisture from the gross weight. This figure provides the foundation for commercial invoicing and yield predictions in spinning mills.
Measurement Protocol
Core samples taken from a shipment undergo scouring and oven drying to reach a state of zero moisture. The resulting clean dry weight represents the actual usable fiber available for processing before any moisture regain is added back for trading. Discrepancies between the estimated and actual yield lead to financial adjustments between the buyer and the merchant.
Yield Evaluation
Processing losses in the carding and combing stages are measured against this baseline to evaluate machinery efficiency. A high clean dry weight relative to the greasy weight indicates a high yield lot with lower waste disposal costs. Technicians use standardized washing protocols to ensure that no residual wax or detergent remains on the sample.
Commercial Standard
Trade contracts specify the testing authority and the method used to verify this value. The clean dry weight acts as the absolute reference point for determining the value of raw material shipments.
