Shed

Definition and Overview

A shed is the space between the upper and lower warp yarns created by lifting part of the warp yarns on a loom and lowering the rest. The process of passing the weft yarn through this space is called weft insertion, and after the weft yarn is passed through, it is beaten up to the cloth fell with a reed to form the fabric.

The action of creating a shed is called shedding. By selectively moving the warp yarns threaded through the heddles according to the weave structure, it creates the warp-up and warp-down relationship needed for plain weave, twill, and other weaves.

Shed Conditions and Their Effect on Weaving

A shed is not a type of finished fabric or a material name, but a temporary space created during weaving. Therefore, the shed itself does not have fabric-specific properties such as texture, appearance, washability, or shrinkage.

The opening and stability of the shed affect how smoothly the weft yarn can be inserted. If warp tension, yarn fuzz or thickness, weave density, or loom settings are not appropriate, it can lead to poor weft insertion or weaving irregularities.

• If the shed is too small, it may become difficult to pass the weft yarn through.
• If warp tension is uneven, the shed may become irregular and affect the weave quality of the finished fabric.
• In complex weave structures, the shape of the shed also changes according to how the warp yarns are moved.

Applications and Role in the Process

Sheds are involved in the weaving process for all woven fabrics made of warp and weft yarns, including shirting, denim, apparel fabrics, and industrial materials. They are not something used differently depending on the garment application or season.

On the weaving floor, the condition of the shed is checked when confirming causes of yarn breakage, weft insertion, and weaving defects. In particular, when adjusting loom operating conditions, the movement of the warp yarns and the shedding state are checked together.

Selection and Handling Notes

From the standpoint of fabric selection, a shed is not usually specified as a material or fabric specification. Fabrics are selected based on the desired texture, strength, thickness, density, weave structure, blend ratio, and finishing process.

There are no shed-specific cautions for sewing or washing. Shrinkage, washing methods, and sewability vary depending on the fiber type, weave structure, density, and processing conditions, so they are checked using the fabric care tag, test results, and the actual material.

Differences from Similar Terms

A shed refers to the space created by separating the warp yarns, while a heddle is a loom part that the warp yarns pass through and that moves them up and down. Warp threading is the preparation process of passing warp yarns through the heddles and reed, and it is not the shed itself.

Weft insertion is the process of passing the weft yarn through the shed. Also, the "sh" in shed originally comes from the shuttle that carries the weft yarn, but on modern looms, opening methods other than shuttle weaving are also called a shed.

Frequently Asked Questions