When talking about covered yarn, one talks basically about elastane yarns that have at least one more yarn wrapped around. Covering however is not exclusively applied to elastane, sometimes also fine wires are covered.
There are two purposes of covering a yarn: one needs an elasticity which normal textile yarn cannot provide while one would still like to keep the apperance of the textile yarn. This is the case for covering elastane where most often a textile Polyester / Polyamide / ... is wrapped around the elastane core.
Covering a yarn can also be in order to hide something. This is most often the case when covering fine wires. The yarn that is wrapped around gives the looks whereas the core (the fine wire) still provides the functionality (like conductivity).
SINGLE COVERED YARN
Single covered yarns are yarns where a second yarn is wrapped around a core yarn.
DOUBLE COVERED YARN
Double covered yarns are yarns where two separate yarns are wrapped around a core yarn.
The second layer of wrapping mainly serves to compensate the twist direction of the first layer.
The second layer of wrapping mainly serves to compensate the twist direction of the first layer.
AIR COVERED YARN
With air covered yarns, the outer yarn is intermingled around the core yarn.
A non-elastic multilfilament yarn can for example be intermingled with an elasthane yarn that is in the core. This construction can be of help in certain embroidery applications.
A non-elastic multilfilament yarn can for example be intermingled with an elasthane yarn that is in the core. This construction can be of help in certain embroidery applications.
CORE YARN
In the example of Elasthane, a non elastic yarn gets wrapped around a twisted elasthane yarn. The elasthane is thus fully covered by the non elastic yarn which leads the yarn as a whole to have the look as well as the haptics of the non elastic yarn. However, the perks of elasthane are still to be noticed when wearing a fabric that is made out of such a core spun yarn by a much higher wear comfort for example.
