The production processes for chemical fiber fabrics are diverse, including melt spinning, solution spinning, and wet spinning. Since different processes affect the fabric's performance and appearance, manufacturers select the appropriate method based on market demand and product positioning.
1. Warping: Depending on product characteristics, this process is generally divided into two types: sectional warping and strip (or drum) warping. In sectional warping, a full warp beam is split into several sections for processing; after sizing, these sections are combined into a single full beam. Strip warping is a widely used method. Both methods share a common feature: warp yarns are first wound onto a large drum and then transferred from the drum onto an empty warp beam.
2. Sizing: The prepared warp beam is mounted onto a sizing machine. The warp sheet passes through a sizing bath to absorb the sizing agent and then through an oven for drying before being wound onto an empty beam. The purpose of sizing is to bond the individual filaments together and increase the yarn's breaking strength, thereby facilitating smooth weaving.
3. Beam Combining: The sized sectional beams are combined according to specifications. Since factors such as tension during warping and sizing can cause variations in length between beams, the process must be based on the shortest beam, with excess length on the longer beams being trimmed off.
4. Shedding/Leasing: To ensure smooth weaving, a leasing machine is used to separate the warp yarns into upper and lower layers (forming a "lease" or shed), after which a cord is inserted into the opening to maintain this separation.
5. Drawing-in and Reeding: The complete warp beam is moved to the drawing-in workshop. Skilled operators pull out the warp sheet and, following the separation established during the leasing process, draw the warp yarns through the heddle frames as required by the product specifications; this step is called "drawing-in." Afterward, a reeding hook is used to pull the specified number of warp yarns into the gaps between the reed dents; this step is called "reeding."
6. Loom Mounting and Weaving: This stage involves setting the reed, hanging the warp beam, installing pattern pegs (for dobby/jacquard looms), and adjusting the weft density. Once these steps are complete, the loom is ready for a trial run.
