Finite element modeling and experimental investigation between the novel drafting and double-apron drafting systems

Abstract

The ring spinning frame featuring the double-apron drafting device is the most widely used method due to its various advantages. The finite element method and experiments were conducted to study the double-apron drafting unit and the novel drafting system. The novel drafting system is characterized by a curved drafting zone and curtate floating zone due to the elimination of the double-apron drafting unit’s double rubber aprons and the innovation of the pins. The finite element results of the double-apron drafting unit and novel drafting system demonstrate that the external friction field in the drafting zone of the double-apron drafting unit is composed of straight-line segments from the pin nip to the middle roller nip. In contrast, the force in the novel drafting system is akin to undulations and exhibits stronger and smoother distribution. In experiments, the double-apron drafting unit and novel drafting system were installed on the ring spinning and compact spinning frames, namely the double-apron drafting unit-ring spinning, double-apron drafting unit-compact spinning, novel drafting system-ring spinning and novel drafting system-compact spinning, to study the slippage rates and yarn properties. It can be seen that the slippage rates of rubber aprons in the double-apron drafting unit-ring spinning vary from 5.84% to 6.89%, while the slippage rates of the lattice apron in the novel drafting system-ring spinning range from 0.39% to 0.66%. In addition, the yarn properties produced by the novel drafting system-ring spinning and novel drafting system-compact spinning, including yarn evenness, imperfections and strength, outstrip those produced by the double-apron drafting unit-ring spinning and double-apron drafting unit-compact spinning.