FLOW AROUND THE ROTATING PIRN AND POWER LOSS. PART2. FLOW ANALYSIS BY FINITE ELEMENT METHOD(FEM) AND CONSIDERATION

An analysis of the flow around a pirn rotating at high speed was conducted using such parameters as the number of revolutions and surface conditions of the pirn. The results are: 1) the flow around the rotating pirn with the boundary conditions of number of revolutions and pirn surface conditions can be analyzed; 2) the velocity vector of..

REVOLUTION IN CHEMICALLY SETTING WOOL YARNS.

The Andar-Wronz 36-end, two-channel Chemset machine uses a package process for chemically setting twist in carpet yarn. The Chemset machine allows simultaneous processing of two independent channels of coiled yarn. The yarn is set with sodium metabisulfite and hot rinsing, dried, and then wound onto packages ready for subsequent processin..

FULLY AUTOMATIC VACUUM AGER FOR STEAMING OF YARNS.

Steaming processes are effective in decreasing tensile and compressive stresses on fibers, which can cause problems during later processing stages. A vacuum ager, which consists of a yarn preheating system, a saturator installed outside of the steaming chamber, and a control system for automatic production, has been designed.

REVOLUTION IN YARN AND FIBER TENSION CONTROL.

During the 1980s, dramatically improved yarn tension control and tension measurement systems were developed. These systems are based on electronic, computerized, and automated process control. Automated technology in yarn tensioners has been especially important for the production of high performance fibers such as aramids or high perform..

SHORT STAPLE YARN SPINNING TO THE END OF THE CENTURY.

Ring and rotor spinning, the two principal methods of producing yarn, will continue to develop toward greater automation. Automated doffing has been realized, but other roving operations have been economically resistant. Complete ring spinning automation requires roving replacement, piecing-up broken roving, and piecing-up after a yarn br..

RING SPINNERS WHIRL AWAY--WEST GERMAN REPORT.

The most popular form of spinning in West Germany is ring spinning. Unlike in the United States, air jet spinning has caught on in only one major company, Textil Gruppe Hof. Rotor spinning is making a comeback due to new and faster methods that increase the degree of automation in the total process. Link spinning has increased the use of ..

ECONOMIC PROCESSING OF TEXTILE WASTES.

The economic and technical feasibility of reprocessing textile wastes are examined, and currently available opening machinery and opening processes are discussed. Present technology is found especially suitable for processing post-spinning wastes for rotor spinning, friction spinning, and nonwovens production. The high level of automation..

FIBER CONTROL.

The influence of rubber cot hardness on cotton yarn quality during the ring spinning process is evaluated. Different shore hardness cot combinations are used. Quality parameters considered include strength, neps, elongation, and yarn evenness. Recommendations for shore hardness during each process are given along with particular reference..

AUTOMATION IN SEMI-WORSTED AND WOOLEN SPINNING.

Karl Meyer offers two systems for the linking of spinning machines and cross winders. Meyer's ADW Winder is for automated assembly winding in carpet yarn spinning plants. Meyer's C-System directly links spinning and winding machines. Its VP-System of indirect linking is recommended for spinners who need equal lengths of yarn on packages. ..

SPINNING IN THE NINETIES

Ring, air jet, rotor, and friction spinning will compete with one another during the 1990s. The selection of one of these technologies to produce a particular yarn will be based on overall performance with regard to economics, yarn quality, and flexibility. The most critical aspect of yarn quality is yarn strength. Ring yarns are still th..