Warp-knitted unidirectional fabric and its production process

Abstract

The invention discloses a low-cost and high-quality warp-knitted unidirectional fabric and a production process thereof. A multiaxial warp knitting machine is adopted. The production process comprises the following steps that 1, weft yarns are laid, wherein the weft yarns are laid in a weft yarn laying zone of the multiaxial warp knitting machine, and it is ensured that the separation distances of the weft yarns are equal; 2, weft insertion and binding are performed, wherein the laid weft yarns are conveyed to a warp knitting machine head of the multiaxial warp knitting machine, are compounded with 0-degree warp yarns and then are bound by binding yarns, it is limited that one weft yarn is inserted every one rotating circle of the machine head and is bound. By adopting the process, the weft yarns equal in separating distance can be produced, the unidirectional fabric with the independently bound weft yarns has a flat cloth cover and is flat and straight, the weft yarns can be rough yarns of 200 tex and 300 tex, the raw materials are relatively lower in price, and the fabric cost is lower. In addition, fabric width adjustment is more convenient, waste is relatively little, the cost can be also controlled through device change, and the process is smooth and stable in operation.

Description

technical field [0001] The invention relates to a warp-knitted unidirectional fabric and its production process. Background technique [0002] With the development of the wind power industry for more than ten years, wind turbine manufacturers and blade manufacturers have put forward higher requirements for glass fiber fabrics for wind power blades, such as: the flatness of the cloth surface, the straightness of the fabric after opening, the fabric in Flow conductivity during resin infusion, especially warp-knitted unidirectional fabrics for wind turbine blade girders. [0003] At present, there are three main production methods for warp-knitted unidirectional fabrics for wind power blades: [0004] Method 1: Use biaxial warp knitting machine or stitch knitting machine to produce, 0 degree glass fiber yarn plus auxiliary light and thin fabric (plain woven or warp knitted fabric with auxiliary weft direction as the main direction, the warp yarn is generally 68tex, The weft y...

AI Technical Summary

Problems solved by technology

The defects and deficiencies of this method are: ① There is a phenomenon of uneven tension in the warp direction yarn of the auxiliary light and thin fabric, and it is difficult to control the tension of the 0-degree glass fiber and the tension consistency of the auxiliary light and thin fabric during the weaving process, so it often causes cloth The surface is uneven, the fabric is not straight, etc., the adjustment is difficult and unstable, and the fabric scrap rate is high; ②Light and light fabrics need to be woven first, and then composite woven with 0-degree glass fiber yarn, which involves two weaving and Loss, high production cost; ③ There are many types of warp-knitted unidirectional fabric widths for electric blades, and light and thin fabrics with fixed widths are used to produce unidirectional fabrics, which waste more light and thin fabrics, and light and thin fabrics with multiple widths are used for production. This has a large backlog of inventory and increases management costs

But there are also defects and deficiencies: ①Because the 90-degree weft yarn uses spun yarns such as 68tex, 100tex, and 136tex, it is easy to break during the production process and the raw material price is high; , it is easy to produce uneven distribution of weft yarns, and the interval is generally 5-10mm wide. The uneven distribution of weft yarns will cause micro-arching phenomenon of 0-degree glass fiber yarns, and uneven fabric surface will occur after too many frequencies

Defects and deficiencies: Since the distance between the weft insertion hooks of the axial warp knitting machine is 12.7mm, and the weft yarn distribution distance of the unidirectional fabric is generally 4mm or 5mm, the weft yarn can only be inserted and cut one by one. Due to the difference in the distance, it will cause The tension of the selvage at the head and tail of the knitting machine is not the same as that of the fabric, resulting in uneven surface of the selvedge

[0007] In summary, there is a lack of a method that can produce high-quality unidirectional cloth at a lower cost