Drafting | Speed frame/Roving frame

Speed frame from the final stage in the spinning preparatory sequence of operations. The main objects of a speed frame process is to reduce the sliver bulk to a diameter suitable enough for the ring frame to spin yarn the dia-meter reduction also known as attenuation is carefully done by one or more drafting systems without disturbing the evenness or regularity. The desired degre of fineness capacity of ring fame.

Drafting of Roving Frame:

   1. Convitional or roller drafting system.   Example: 3 over 3
   2. Modern drafting system (Without apron/With apron)

Example:

• Casablanks two zone process system
• Casablanks U-three system
• SKF-Pk 2500 system
• SKF PK-1600 Drafting system
• SKF-Pk 1500 system

Break draft:

The draft between back and middle roller varied from 1.1-1.5 which is known as break draft. The amount of break draft depends upon the following parameters:

1. The twist in the creeled materials
2. The crimp in the fiber
3. The elasticity of the fiber
4. The bulk of creled materials
5. The centre to centre bottom fluted roller setting

Function of break draft:

1. To prepare the processed sliver for final drafting in the front zone.
2. Engage to break the twist in the material to prepare it for final drafting.
3. Helps to acquire higher draft between middle and front roller.

Roller draft: This drafting system is done by the help of only some pairs of roller is called roller draft.

Apron draft: This drafting system, apron is used along with roller. So, this drafting system is called roller draft.