# GATE (TF) Textile 2022 Question Paper Solution | GATE/2022/TF/19

###### Question 19 (Textile Technology & Fibre Science)

Assume that there is no compression of roving during winding and each coil of a layer is placed directly over the coil of the previous layer. A full roving bobbin consisting of 50 layers of roving is wound on an empty bobbin of 60 mm diameter. If the diameter of the roving is 1 mm, then the diameter (mm) of the full bobbin (in integer) is ___.

No. of layers of rovings on empty bobbin=50

Diameter of empty bobbin=60mm

Diameter of roving=1 mm

The diameter of full bobbin=?

Dia of full bobbin=Dia of empty bobbin+dia of 50 layers of roving

=60+50 x 2 x dia of rovings (Multiplied by 2 because roving will covered empty bobbin from both side)

=60+50 x 2 x 1

=60+100

=160 mm (Ans)

### What is roving bobbin ?

A roving bobbin is a type of spool used in the textile industry, particularly in the production of fibers, yarns, and textiles. A roving bobbin contains a long, continuous strand of fibers that have been loosely twisted together. The fibers on the bobbin can be fed into various machines for further processing, such as spinning, weaving, or knitting. The roving bobbin allows for a smooth and continuous flow of fibers during the manufacturing process, which can lead to higher quality and more efficient production.

### What is bobbin ?

A bobbin is a spool-like object used for holding and dispensing various materials such as thread, yarn, wire, or filament. Bobbins are commonly used in textile manufacturing, sewing, and weaving to store and feed thread in a controlled manner. They are also used in electrical machinery, such as motors, to store wire and in many other applications where winding and storing a long, thin material is necessary. Bobbins come in different sizes and shapes, and the specific design can vary depending on the material being stored and the intended use.

### What is roving ?

Roving is a type of semi-finished textile material that consists of long fibers that have been loosely twisted together. It is a stage in the production of fibers, yarns, and textiles, and is used as a feedstock for further processing. Roving is produced by aligning fibers parallel to each other and twisting them together to create a long, continuous strand. The amount of twist in the roving can vary, and the fibers may or may not be crimped, depending on the desired end-product. Roving is often used in spinning and weaving processes to create yarns, and is known for its flexibility and ability to be spun into fine, even threads.