Question

Use of scrambler roller in condenser card gives

• A. Random laid webs
• B. Cross laid webs
• C. Parallel laid webs
• D. Continuous laid webs

Hint:

• Condenser Card Used in woolen system or for nonwovens.
• Scrambler Roller (Randomizer Roller) A roller designed to disrupt fiber orientation in a web.
• Its purpose is to create a web with more random fiber orientation} (isotropic properties), as opposed to the parallel-laid orientation typical of a standard card web.
• This is useful for nonwovens requiring similar strength in MD and CD.
• Cross-laid webs are formed by cross-lappers. Parallel-laid is the typical output before scrambling.

Answer 1

The Correct Option is A

A condenser card (often used in woolen carding or for nonwoven web formation) is different from a conventional cotton card. Its purpose is often to produce a web that is then divided into "slubbings" or "rovings" for woolen spinning, or to produce a web for nonwovens. A scrambler roller (also known as a randomizer roller or eccentric roller) is a component sometimes used in carding or web-forming processes. Its function is to disrupt any preferred orientation of fibers in the web coming off the main carding cylinder (doffer web) and to create a more isotropic or randomly laid web. This is particularly relevant for nonwoven applications where equal strength and properties in all directions (MD - machine direction, CD - cross direction) are desired. Let's consider the options:

• (a) Random laid webs: A scrambler roller, by its action of disturbing the fiber orientation, promotes a more random arrangement of fibers in the web. This is its primary purpose.
• (b) Cross laid webs: Cross-laid webs are formed by a cross-lapper machine, which lays down successive layers of carded web at an angle (often 90 degrees) to each other to build up thickness and achieve balanced strength. A scrambler roller does not create this layered cross-laid structure.
• (c) Parallel laid webs: Carding machines inherently produce a web where fibers are predominantly oriented in the machine direction (MD) due to the carding action and doffing. This is a parallel-laid web. A scrambler roller is used to *reduce* this parallelism and introduce randomness.
• (d) Continuous laid webs: This describes the continuity of the web, not its fiber orientation. All carding processes produce a continuous web (until it's divided or collected).

The specific function of a scrambler roller is to introduce randomness into the fiber orientation within the web. Therefore, it gives random laid webs. \[ \boxed{\text{Random laid webs}} \]