Denim Weaving Technolog (2)

Denim Weaving5

Denim Weaving Process Characteristics

Denim Weaving4
  • General Genim Weaving Process Characteristics

Denim is different from general cotton cloth, yarn count coarse, warp and weft density is small, but the fabric tightness is large, the required tension on the machine is large, beating the weft strength is large, generally use high back beam, early opening (300 ° ~ 310 °) of the weaving process, and 3/1 twill varieties than 1/1 plain varieties can improve the amplitude of the back beam is larger, in the context of considering the reduction of the fabric surface of the free yarn, reduce the driving traces of the premise of raising the back beam Height, so in the specific formulation of the weaving process, the height of the back beam 3/1 twill varieties higher than 2/1 twill varieties, 2/1 twill varieties higher than 1/1 plain varieties.

  • Hemp Cotton Denim Weaving Process Characteristics

Hemp cotton denim due to hemp cotton yarn breaking strength is small, the yarn details are prone to the shortcomings of fracture, so the production to reduce the warp yarn breakage rate as a prerequisite. Generally used to lengthen the length of the rear shuttle mouth to ease the impact of the warp yarn opening elongation, while appropriately increasing the amount of rear beam swing, improve the relative humidity of the workshop. After the shuttle mouth length of 500 ~ 550mm is appropriate, too long is not easy to watch the operation of the car workers, after the beam swing amount of 10mm or so, strict control of the relative humidity of the production workshop, the relative humidity in about 80%.

  • Bamboo Denim Weaving Process Characteristics

Bamboo denim its bamboo section of the manifestation of the bamboo is through the warp to the bamboo node to lift the weft of the weft floating point highlights, and because the cloth machine on the front of the page heald and the back of the page heald to the weaving mouth between the existence of the distance between the differences in the pressure difference between the front and back of the heald warp yarns and weft yarns woven on the pressure difference between the front and back of the heald is large, after the heald is small, the node for the bamboo node highlighting the effect of the difference between the bamboo node in general by the bamboo section of the bamboo yarn with the ordinary warp yarn and use the bamboo section of the bamboo yarn worn in the front of the heald, the bamboo effect of the bamboo nodes Generally speaking, when warp yarn is used with normal warp yarn, the bamboo node effect will be obvious when the bamboo node yarn is worn in the front heald; on the contrary, it will not be obvious. The same principle, the weft bamboo pitching is also very delicate, in general, the choice of the front of the heald in the lower pitching bamboo weft yarns, weaving through the front of the heald of the large interweaving pressure, so that the bamboo weft floating point is more visible on the surface.

Denim Production Process Cases

Denim Weaving5

Lightweight Large Jacquard Denim Production Process Cases

  • Fabric specifications

26S combed cotton / hemp fiber + 26S combed cotton / hemp fiber bamboo × 150 D/144 F polyester + 40S combed cotton, 134 × 80, gram weight 215 g / m2, the fabric tissue with large jacquard, width 59 inches.

  • Weaving process

Weaving process: Weaving on Bigelow GT511 electronic jacquard machine. Hemp fiber/cotton blended yarns are highly hygroscopic and prone to sticking, while polyester weft yarns are smooth and not easy to hold. Therefore, the selection of the machine parameters is very important, and the relative humidity in the workshop is very high. The process principle of “early opening, medium tension, large bobbin mouth” is adopted. The process parameters are as follows: opening time 22°, weft draw-in time 10°, height of the back beam 15 cm, height of the bobbin opening 8 cm, predefined tension 1.2 kN. The bobbin opening is clear, which is good for the weft yarns to fly, and the efficiency of the weaving process reaches 95% after taking the above measures.

  • Production quality control

The total number of warp yarns of this variety is large, and there are two kinds of warp yarns: common yarns and bamboo yarns. In order to fully reflect the style characteristics of jacquard fabrics made of hemp pulp fiber/cotton blended fabrics, and to ensure that the surface of the fabric is even and full, two stranding rods are placed between the back beam and the warp stopping piece, and the warp yarns are divided into three stranding layers by using these rods (common varieties can be stranded in two layers), so as to prevent the top stranding of two kinds of yarns from breaking off and preventing the top stranding of two kinds of yarns from occurring, and to make the warp yarns evenly taut, and the warp yarns are clearly defined. The warp yarn tension is even, the shuttle mouth is clear when weaving, and the fabric pattern has strong three-dimensional sense, moderate floating length and natural luster.

Denim Weaving6

Heavy Denim Production Process Cases

  • Fabric specification

Warp and weft density 83 × 83 tex, warp and weft density 267.5 × 157 roots / 10 cm, raw material cotton / viscose / polyester (40 : 30 : 30), the fabric organization for the three on one broken twill, warp tightness 90.1%, weft tightness 52.9%, grammage 450.5 g/m2, fabric thickness 0.54 mm.

  • Weaving process

The fabric has a coarse warp yarn number, and the organization is a broken twill organization with three tops and one bottom. If the heald flatness is taken too late, there will be more squeezing on the weft clamp, which is not conducive to the rapid weft draw of the rapier; if the heald flatness is taken too early, the weft yarns can be tightly drawn in and less anti-drawn, but the fabric texture will not be clear enough. Therefore, a moderate opening time of 315° to 320° is desirable. The opening time of the rapier weaving machine should be adjusted so that the left side of the heald frame is flush with the head of the weft-feeding rapier at 5 cm from the fabric edge, to ensure that the rapier draws in the weft efficiently. The height of the bobbin opening is 32 mm. The height of the bobbin opening is a key parameter and should be configured appropriately. Otherwise, the rapier head is subjected to excessive friction and extrusion by the warp yarn, which affects rapier weft introduction and makes weaving difficult. Adoption of an appropriately low warp position line of the back beam makes the fabric surface even.