Yarn Formation In Rotor Spinning Machine

Yarn Formation in Rotor Spinning

Yarn Formation in rotor spinning :- The rotor rotates at high speed creating a centrifugal force.

• To start spinning, a length of yarn already wound onto the package of the take-up mechanism is threaded through the nip line of the delivery rollers and into the draw-off tube.
• Because of the vacumm, the tail end of this yarn is sucked into the rotor.
• The rotation of the rotor pulls the yarn end onto the part collected ribbon of the fibres through the air drag and the centrifugal forces, and simultaneously inserts twist into the yarn tail. 
• A little of this twist propagates into that part of the ribbon in contact with the yarn tail,binding it to the yarn end.
• The yarn is pressed against the rotor wall by the high centrifugal force, and the separation point therefore rotates within the rotor.
• Each revolution of the yarn at this point inserts one turn of the twist penetrates in to the fibre.
• Ring in the collection groove, where the fibre are bound toghter to form a yarn.

                                            

                                                Fig :- To form a yarn formation on rotor    

Technical Data/ Machine Parameters :-  

1. Technological setting parameters:

Fiber length	Natural and man made fibers up to 60 mm
Sliver weight	Nm 0.14 - 0.40; Ne 0.08 - 0.24; ktex 7.0 - 2.5
Yarn count range	Nm 5 - 100; Ne 30 - 60; ktex 200 - 10
Draft range	40-400fold
Twist range	T/m 196 1 500/TPI 5 38
Winding helix	adjustable between 30° and 40° in steps of 1°

2.Production related setting parameters :

         

Rotor speed	35 000 - 160 000 rpm
Opening roller speed	6 000 - 10 000 rpm
Delivery speed, cylindrical	up to 350 m/min (240 rotors) up to 270 m/min (500 rotors)
Delivery speed, conical	up to 60 m/min (500 rotors)
Package weight, cylindrical	up to 6 kg or 350 mm diameter
Package weight, conical	up to 270 mm diameter

3.Machine Data:-

Number of rotors, total	up to 500
Numbers of rotors/section	20 or 24 rotors depending on machine manufacturer
Number of sections	up to 25 (with 20 rotors/section) up to 20 (with 24 rotors/section)
Number of robots	up to 4

           1.  Opening roller   :-      Dia. – 50-80mm

                                      
          Wire point :-  (i)  For cotton –Saw tooth type(65°,18pt/cm)

                               (ii) For MMF – Pin type (90°,15pt/cm)

           Speed – 3000-10,000rpm, 

  

 2. Rotor :- Cup shape like element (circular form)

                               Dia. – 30-50mm

                               Speed -  30,000 – 1,20,000 rpm
                                             [upto 1,50,000rpm(latest m/c)]

·         

•     Ratio between fiber length and rotor dia.1:1.5 (Smaller the dia. Higher the speed)
•     Circumference :– 3–5 times of fiber length
•     Count below 20^s
•     Delivery rate – 100mt/min
•     Transportation of fiber through air pressure
•     Fiber flux – below the 10 fiber
•     Coating on roller – Nickle, Teflon
•     Type of groove – G/U/S/T/V
•     Type of doffer tube :- Plain, Groove, Grip, Knotch, Circular, Steel, Metal
•     Transportation tube :- V-shape, Circular, Smooth
•     Rotor m/c production is 5-8 times more then ring frame m/c.