This document discusses friction spinning, also known as DREF spinning. It is an open-end spinning system that uses frictional forces between two counter-rotating rollers to twist individual fibers into yarn. The key steps in friction spinning are feeding fibers onto a drum surface where they are stacked into a bundle, wrapping around the bundle as it rotates between the rollers, and inserting twist as the yarn tail is pulled by a delivery roll. There are different types of DREF friction spinning systems including DREF-1 through DREF-3000, with DREF-2000 employing a rotating carding drum to open slivers into single fibers before carrying them into the nip of two perforated spinning drums where they are

1. Prepared by
 Takbir Ahmed
 29th Batch
 Dept. Of Textile EngineeringI
 Daffodil International University.

2. Hello Everyone

3. Friction Spinning

4. Friction Spinning
 Friction (DREF) spinning system is an Open-end
spinning system.
 It is known as DREF spinning system.
 The frictional forces in the spinning zone the yarn formation
takes place.
 External surface of two rotating rollers is used to twist
individual fibers.

5. Schematic view of friction spinning

6. Principal of Friction Spinning
 Fibers are delivered onto the drum surface, which transports
and stacks the fibers to the fiber bundle rotating between
two surfaces moving in opposite directions.
 The fibers wrap around the bundle surface.
 wrapped fiber bundle (yarn tail) is tugged by the yarn
delivery roll.
 Therefore twists by fiber arrangement are generated.
 Due to separate yarn winding and method of twist insertion,
it has capability to go for high production rate.

7. Yarn Formation
 3 steps
 Feeding of fibers
 Fibers integration
 Twist insertion.

8. Types of DREF Friction Spinning
 DREF-1
 DREF-2
 DREF-3
 DREF-5
 DREF-2000
 DREF-3000

9. DREF-2000
 It is the latest development in friction spinning demonstrated
in ITMA 99.
 DREF-2000 employs a rotating carding drum for opening the
slivers into single fibers and a specially designed system
being used for sliver retention.
 The fibers stripped off from front the carding drum by
centrifugal force and carried into the nip of the two
perforated spinning drums.
 The fibers are subsequently twisted by mechanical friction on
the surface of the drums.
 Drums are rotates in the same direction.

10. DREF-2000

11. THANK YOU