Research On The Weaving And Formability Of Helmet-shaped Fabrics

Textile composites usually use two-dimensional fabrics as reinforcements.In order to avoid folds on the surface of two-dimensional fabrics,it is usually necessary to cut and suture the two-dimensional fabrics,which not only reduces the production efficiency,but also reduces the production efficiency.The continuity of the reinforcements is also affected.In order to solve this problem,the copying fabric is used as the reinforcement of the curved surface structure composite material.The copying fabric refers to the woven fabric with the required shape according to the requirements of the fabric forming,which can be transformed into the traditional loom.The loom has the ability to mechanize the production of copying fabrics.This topic mainly through the elaboration helmet shape fabric on the machine weaving In this paper,the weaving method of helmet fabric is introduced in detail,the modification of traditional loom and the design of equal weft density of fabric are introduced in detail,the phenomenon of bad adhesion between copying fabric and die is discussed,and the index is established to evaluate the forming effect of copying fabric.The weaving equipment of copying fabric is divided into special equipment and traditional loom.The cost of special equipment is high and the range of application is small.The common weaving methods of copying fabrics on traditional looms include non-uniform coiling method,planarization method,weave combination method and circular weaving method.The four methods have different weaving principles and suitable fabrics,but they can be used to weave most copying fabrics.The commonly used weaving methods for helmet-shaped fabrics are planarization,warp-density weaving and irregular roll coiling.The three methods of forming curved surfaces are different in principle,and the forming effect of woven fabrics is also different.Compared with the planarization method and the warp density weaving method,the special roll coiling method has the advantages of low cost,high weaving efficiency and good formability.In order to smooth and shape the fabric,the traditional loom’s warping,tension control and coiling mechanism were reformed.Because of the curved structure of the helmet-shaped fabric,the weft density distribution will be uneven in the fabric.In order to improve this phenomenon,the short weft,which is only interwoven with some warp yarns,is introduced in the weaving process of the fabric.After finishing,the adhesion degree between helmet fabric and die can be used as an index to evaluate the forming effect of helmet fabric.In this paper,the adhesion degree of replica fabric and die is called the coefficient of copying fabric.In this paper,we use the height comparison between the replica fabric and the corresponding point on the surface of the die to express the adhesion coefficient of the copying fabric.The formula is:α=1|H’-H/H’|.The adhesion coefficient can be used to compare the forming effects of different fabrics and different regions of fabrics,and also to compare the forming effects of different weaving methods,which provides the basis for how to select the weaving methods.