Raw yarn (rotating cup yarn) (warp yarn - winding - warping - indigo dyeing and sizing) - machine strengthening - singeing - sizing - tilting (weft straightening) - anti-shrinkage finishing - drying and setting - finished product

(1) Yarn twisting:

In the production of denim, for the warp and weft yarns, especially when using rotor yarns with a higher twist as the warp and weft yarns, moisture and heating should be carried out to stabilize their twist.

The intention is to ensure the smooth progress of warping and dyeing processes, reduce weft detachment, weft shrinkage and curling during weaving, and improve the quality of the fabric.

Requirements: Stabilize the twist of the yarn by methods such as increasing tension, providing moisture, and heating, with a reasonable moisture regain rate of 8% to 9%

(2) The significance of winding denim with yarn

(1) Change the roll packaging form

(2) Remove the defects of the yarn by removing the harmful defects on the original yarn in the winding

(3) Improve the tension of the yarn

(4) Reduce the foot yarn

(3) Straightening the scriptures

one The primary intention is to ensure that the tension, arrangement and winding of the yarn pieces or rope bundles are uniform, and to wind a certain amount of bobbin yarn at a uniform tension and regular length evenly and tightly on the warp shaft or specially made ball shaft, preparing for the subsequent dyeing and sizing processing.

2 The primary type is the 1452A or GAI2I batch warping machine. These warping machines have been able to meet the quality requirements when used in the combined dyeing and sizing production line.

The dyeing and finishing production process of denim

The manufacturing process of denim is rather unique. It is a product made by first dyeing the warp yarns with indigo and sizing them, and then weaving them.

one Dyeing and sizing

There are three types of indigo dyeing for denim warp yarns: rope dyeing, sheet dyeing and loop dyeing. The first two are connected to the sizing yarn, while the latter is dyed and then sizing.

(1) Rope-like dyeing

(Ring spindle yarn) Interlocking and winding -(rotating cup yarn) warping - Rope frame - indigo continuous rope dyeing - Long chain shaft warp - sizing - weaving - fabric inspection - Post-treatment - pre-shrinking and finishing

(2) Dyeing and sizing of sheet yarns

(Ring opening yarn) Interweaving and winding -(rotating cup yarn) warping - Indigo dyeing and sizing - weaving - fabric inspection - Singeing - Post-treatment - pre-shrinking and finishing

(3) Suspended ring dyeing

This method employs a dyeing tank in which the warp yarns are repeatedly dyed in a cycle until the required depth is reached. The technological process of dyeing and sizing is:The process of warp yarn feeding - alkali boiling (or wetting)- water washing - indigo dyeing - air permeation oxidation (indigo dyeing)- air permeation oxidation is carried out in a cycle of six times - water washing four times - drying - yarn storage - sizing - drying - winding