Friday, August 6, 2010

Some Synthetic Yarn Terminology

•BR-TL: Bright Triloble

•SD: Semi Dull

•SCD : Set Yarn

•FD: Full Dull

•BK: Black Dope Dyed

•SET: Set Yarn

•SIL: Slightly Intermingle

•WIL: Heavy Intermingle

POY: Partially oriented yarn
FOR: Fully oriented yarn
FDY: Full drawn yarn
SDY: Spin draw yarn [spin draw process is used for making partially oriented yarn]
DTY: Draw textured yarn
ATY: Air textured yarn
SBC: Stufferbox crimped yarn
FTY: False twist yarn
TFY: Twisted filament yarn
DT Yarn: Draw twisted yarn
DW Yarn: Draw winded yarn
ITY: Improved textured yarn
Bsy: Bi-stretch yarn

False Twist Yarn

http://www.polyspintex.com/ups/text04.htm

Intermingled Yarn

http://www.polyspintex.com/ups/text03.htm

Air Textured Yarn

http://www.polyspintex.com/ups/text05.htm

Draw Textured Yarn

Why do we texture yarns?
To give synthetic yarns special properties such as stretch, bulk and the appearance of natural fibers.

The false twist texturing principle
For the texturing process the texturing industry has the choice of a variety of DTY machines produced by various manufactures around the world. False twist texturing machines, regardless who offers them, all work on the same principle. The schematic below shows the most important steps in the manufacturing of DTY.



POY, which stands for Partially Oriented Yarn, is now the standard feed yarn for the texturing process. It is a continuous filament yarn spun at a speed, which is, for example for polyester, around 3200 m/min.

Shaft 1 is the input feeding device for the POY. From here the yarn is fed to Shaft 2. When POY is fed into the machine, the yarn has to be drawn. The speed of shaft 2 is always higher by the factor of the necessary draw ratio for the particular yarn and process. The yarn is simultaneously twisted and drawn. The twisting is done with a friction device, such as a set of rotating friction disks. But there are other twisting devices such as belts. After Shaft 1 there is a yarn heater, which heats the yarn to a temperature where it can be thermo-set. Right after the heater is normally a cooling plate, which must cool the yarn to a substantially lower temperature in order to permanently thermo-set the twist. As the yarn is released from Shaft 2 we observe how each single filament is trying to assume the three dimensional helix formation it was set in. The result is a voluminous bulked stretch yarn.

Thursday, August 5, 2010

Bangladesh Apparel Trade 2009-2010

  • Total exports of knit and woven apparel:
    July 2009-June 2010: US$12.496bn
  • Exports of knit apparel:
  • July 2009-June 2010: US$6.483bn (year-on-year change: +0.84%)
  • Exports of woven apparel:
  • July 2009-June 2010: US$6.013bn (year-on-year change +1.60%)
  • Sources: Government run Export Promotion Bureau Bangladesh, BGMEA and others.