Textile & Fashion World

Tensioning Device
Tensioning device, a device to detect thick spots or slubs in the yarn & a stop motion which causes the winding to stop in the case of a yarn break or the depletion of a supply package. The yarn is directed into this zone by a guide.

Functions of Tensioning Device:

1. To allow the maintenance of proper tension in the yarn in order to achieve a uniform package density.
2. The tensioning device also serves as a detector for excessively weak spots in the yarn which break under the added tension induced by the tension device.

Effects of Tension Variation:

1. Too high tension may damage the yarn whereas too low tension can lead a unstable packages which will not unwind cleanly.
2. In case of man made fiber high tension can cause molecular change which affects the dye ability, so that variations in tension ultimately show as apparently random variation in color shading.
3. In case of winding staple yarns, yarn tension may break thin place of yarn.

Requirements Which Influence the Choice of Tensioning Device:

• The device must be reliable.
• It must be easily threaded.
• It must neither introduce nor magnify tension variations.
• It must not introduce difference in twist.
• It must not be affected by wear.
• It must be easily adjustable.
• It must not be affected by presence of oil or dirt.
• It must not encourage the collection of dirt & lint.
• It must be capable of easy cleaning.
• The operating surfaces must be smooth.
• It must be inexpensive.

Types of Tensioning Device:

Tensioning device can be classified in 2 ways as follows-

1. Depending on the type of the working member acting on the yarn.
2. According to the working principle.

Depending on the type of the working member acting on the yarn the tensioning devices are the following types: 

• Ball type.
• Washer type.
• Disc type.
• Roller type.
• Comb type.
• Two zone type.

According to the working principle the tensioning devices are the following types:

1. Capstan (multiplicative) tensioner.
2. Additive tensioner.
3. Combined tensioner.
4. Automatic tensioner.

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