RING FRAME MACHINE

Ring Frame  Working diagram :

 

A - unwinding zone

B - drafting zone

C - winding zone

Objective of ring frame machine :

1. Attenuate the roving untill the required fineness achieved.
2. To impart strength to fibre strand by twisting it.
3. To wind up the resulting yarn in a form of suitable for storage, transportantion and futher processing.

Operating principle :

	The roving bobbins (1) are creeled (A) in appropriate holders (3). Guide rails (4) lead the rovings (2) into the drafting arrangement (5) which attenuates them to the final required count.
	The drafting arrangement (B) is inclined at an angle of about 45 – 600. It is one of the most important assemblies on the machine since it has considerable influence on irregularities present in the yarn.
	After the drafting arrangement, the machine have twisting and winding zone (C).
	Upon leaving the front rollers, the emerging fine fiber strand (6) receives the twist needed to give it strength. This twist is generated by the spindle, which rotates at high speed. Each revolution of the spindle imparts one turn of twist to the fiber strand. Spinning of the yarn is thus complete.
	In order to wind up the twisted yarn to bobbin mounted on Spindle( 8) , a traveller (9) is required to cooperate with the spindle. The traveller moves on guide provided on the ring (10) encircling the spindle.
	The traveller has no direct drive; instead, it is carried along by the yarn it is threaded with. The speed of the traveller is lower than that of the spindle owing to significant friction generated between the traveller and ring.
	This difference in speed enables winding of the yarn to bobbin.
	Winding of the yarn on to the bobbin is done by raising and lowering the ring rail. The traverse stroke of the ring rail is less than that of the bobbin height. The ring rail must therefore be raised by small amount after each layer of coils. Cross-section of the machine : The cross-section of a typical ring spinning machine. The ring frames are two sided machines with the spinning positions located on both sides of the machine. Each spindle is a spinning position. The spindle rail houses the spindles. The creel housing the feed roving bobbins are arranged in two rows on each side of the machine. The drafting arrangement is carried on the roller beams. Each intermediate section stands on two feet adjustable in height by means of screws, thereby permitting easy leveling of the machine. In modern machines, an auto-doffer is also provided. Including the auto-doffer, the width of the machine varies from 800 to 1000 mm (up to 1400 mm when the doffer arm is swung out). Today, the machine length can reach 50 m. Spindle gauges usually lie between 70 and 90 mm. ADVANTAGE : It is universally applicable, most of the textile fibres can be spun to required fineness. The yarn spun from this machine demonstrate excellent quality features like uniform structure and good strength. It is easy to operate as compared to other spinning machines. The “know-how” for operation of the machine is well established. It is flexible as regard to quantities in terms of blend and lot sizes. DISADVANTAGE: More process stages. Roving stage exists as an extra process compared to the other systems. The high speed of the traveller damages the fibers. The capacity of the cops is limited. Energy cost is very high.