History and Experiences with Small-Scale SampleEvaluations of Cotton, and Potential for Improvement

The origin of the Small-Scale Spinning Test, which is used to characterize the quality of samples of cotton weighing between 15 and 30lbs (6.8 and 13.6 kg), lies in the annual cotton crop assessments performed by the USDA’s Agricultural Marketing Service and the Textile Research Center of Texas Tech University. Each program of evaluation involved thorough testing of the raw cotton followed by the ring spinning of at least two yarns by the ring spinning route. The machinery used was of industrial size to emulate production conditions. The Small-Scale Spinning Test advocated by the USDA’s SRRC has been extended to include fabric manufacture, yet condensed by a need to conserve space that has required the elimination of one drawframe from the sequence of machines employed.

The objectives of this study are three-fold;

• to describe the evolution of the Small-Scale Spinning Test, and its execution,
• to examine the importance of the drawframe in the process, and
• to identify a new method of operation in which setup errors are minimized when the same machine is used to perform both passes of drawing.

The use of 27tex (Ne22) yarn throughout more than 60 years of small-scale evaluations is noted. Control of linear density throughout processing is critical to minimize waste and machine downtime. Benefits can accrue from the use of autolevelling for both passes of drawing, and reducing the chances of error by eliminating four of the five changes previously required, as well as decreasing machine downtime.