Weft Insertion
Weft insertion is a weaving process in which the weft yarn is passed between the opened warp yarns on a loom, and then beaten in with the reed to form the fabric structure and fabric width.
Contents6 sections
Definition and Overview
Weft insertion is one of the basic processes used to make woven fabric. The weft yarn is passed through the shed, the space formed between the upper and lower warp yarns, and then beaten up to the cloth fell with the reed, interlacing the warp and weft yarns.
- The process of passing the weft yarn through the shed
- The process of packing the weft yarn to the cloth fell by reed beating
- The process of repeating this action to weave fabric continuously
Effect on Hand and Appearance
Weft insertion itself is not a fabric name or a weave structure, but it has a major effect on hand and appearance depending on the type, thickness, twist, color, and pick density of the weft yarn. Making the weft yarn thicker or increasing the pick density generally makes the fabric easier to achieve more body and a denser look.
When different colors are used for yarn-dyed warp and weft yarns, the crossing creates color effects. Also, when decorative yarns or stretch yarns are used for the weft, the surface texture, fullness, and stretch properties can be designed.
Main Applications and Differences by Loom Type
Weft insertion is used in the production of all kinds of woven fabric, including shirting, trouser fabric, denim, coat fabric, lining, and industrial materials. Suitable seasons and items are determined not by the weft insertion process itself, but by the material, yarn usage, weave structure, density, and finishing process.
On shuttle looms, a shuttle is used to pass the weft yarn, while on modern looms, the weft yarn is inserted by methods such as air-jet, rapier, and gripper. The yarns, fabric widths, and production conditions that are easy to handle differ by method.
Points to Note in Planning and Handling
When selecting fabric, check not only the material and density of the weft yarn, but also the stretch, shrinkage, skew, and pattern appearance in both the warp and weft directions. Especially for checks and stripes, it is also necessary to check pattern misalignment in the weft direction and differences in appearance from lot to lot.
Post-wash shrinkage and twisting are caused by a combination of fiber properties, yarn twist, weave density, finishing processes, and more. Before cutting, if necessary, let the roll relax and wet out the fabric, and before sewing, it is important to adjust the grain and the condition in the weft direction.
In sewing, for fabrics that stretch easily in the weft direction or structures where the weft yarn tends to float, adjust feed amount and presser foot pressure. To avoid seam puckering, slippage, and pattern misalignment, carry out trial sewing and washing tests before full production.
Differences from Similar Terms
Weft insertion refers to the weaving process of passing the weft yarn through the loom. Plain weave, twill weave, and satin weave are weave structures that show the order in which warp and weft yarns cross, and they are a different classification from weft insertion.
The expression weft yarn insertion is sometimes used with the same meaning as weft insertion, but in the materials and knitting fields, it can also refer to a structure or specification in which yarn is inserted in the weft direction. In specifications and product descriptions, check whether the subject is a woven fabric manufacturing process or a structural term.
Frequently Asked Questions
Is weft insertion a type of fabric?
Weft insertion is not a type of fabric; it is the process of passing the weft yarn between the warp yarns when making woven fabric. The characteristics of the fabric are determined by the weave structure such as plain weave or twill weave, the yarn material and thickness, warp and weft density, and dyeing or finishing processes.
Does the difference in weft insertion change fabric shrinkage?
Shinkage is not determined by the weft insertion method alone. The weft yarn material, twist, pick density, weave structure, dyeing and finishing, and washing conditions all have an effect. In planning, it is important to check shrinkage rates separately for the warp and weft directions.
Are weft insertion and weft yarn insertion the same?
In contexts that explain the weaving process for woven fabric, they may be used with a similar meaning. However, weft yarn insertion can also indicate a structure in which yarn is added in the weft direction in knitting or materials. Use them appropriately by checking the intended use and the material involved.
