GENERAL MECHANICS AND MECHANICAL ENGINEERING INVESTIGATION OF THE UNEVENNESS OF THE PILE HEIGHT LENGTH IN COMPLEX FABRICS

. Objective. In this article, the unevenness of pile height length was analysed in complex fabrics. During the research, characteristics, structures, shapings and the piles of towel samples have studied. In this research, the advantages and disadvantages of the complex weavings were analyzed and some recommendations gave below. Methods. During the research, weaving samples were weaved on ITEMA 9500 machine and RF 505 Picanie machine. An unevenness of pile height length was measured by hand methods, and in this process, linear, tweezers and black flat table were used to get results. Results. In the research, three samples have taken for the experiment in one square metre of fabric. The piles of each sample were measured on both two sides: back and face. The length of the towel sample pile was different. Conclusion. The samples that were weaved on the ITEMA 9500 machine at the factory of “ARTSOFTTEX” were given the best results. Because the samples unevenness of the pile height had been more even than others. When we use more even threads and made the balance of tension for the weaving towels possibly, then we can get more even pile towels.

Methods. In terry fabrics, loops are formed on both sides of the fabric [14]. Another method of producing pile fabrics is face-to-face weaving in which a double fabric, one on top of the other, is made with vertical links provided by the extra set of warp yarns. The linking warp yarn is then cut to produce velvet piles. It is also possible to produce pile effects through knitting [15][16][17][18][19][20][21][22][23][24][25][26] or even from nonwoven fabrics. Pile yarn is traditionally a spun yarn, particularly from wool, but there is increasing use of bulked continuous filament yarns. In picture 1, 3-pick terry pile designation was taken during the research exposed below (Fig. 1.).
The towel which is in the picture one above weaved on ITEMA 9500 machine at the factory of "ARTSOFTTEX" terry products and on RF 505 Picanie machine at the factory of "CHASHMAI SAFED". The terry pile is a warp pile structure that has loops on its surface that are formed by certain warp ends [27 -34]. Terry piles are constructed by using one series of weft threads and two series of warp threads. The warp threads consisted of one for the ground and the other for the pile. The ground warp interlaces with the ground weft to form the ground cloth. This ground cloth holds the loops formed by the pile ends and allows the looped portion to project on the fabric surface [35][36][37][38][39][40][41].
In our research, the loops were double-sided: face and back. During the research, we measured each pile's height and its length (Fig. 2).
There are some different terms in this research. For example, pile ratio, pile height, loop geometry etc. .

Fig. 2. Cross-section of towel sample. PH-pile height
Pile height may be defined as the vertical height of the terry loop from the centre of the terry fabric. It gives an indication of the fabric quality, generally higher PH gives a fabric of better quality [42][43][44][45][46][47].
Results. Three samples have taken for the experiment in one square metre. The piles of each sample were measured on both two sides: back and face.
The following table 1 has shown the number of pile height length on two different machines (table 1). The diagrams were used for the assessing results of the above table 1. In this diagram, the yellow line is the graph of the face side of the towel sample and also the green line is the graph of the back side of the towel sample. This diagram is shown that the length of towel sample piles was different each other, that, pile height length that was between 9,5 and 10 mm were increased in both side of towel samples. And also, if the diagram focuses on one vertical line, the pile height length of towels will be the same on the towel surface. These diagram results were taken on RF 505 Picanie machine at the factory of "CHASHMAI SAFED".

Fig. 4. ITEMA 9500 machine results
In this diagram also the yellow line is the graph of the face side of the towel sample and also the green line is the graph of the backside of the towel sample. And diagram results were taken on ITEMA 9500 machine [21] at the factory of "ARTSOFTTEX". The results showed that the length of towel sample piles was different from than RF 505 Picanie machine. Because the numbers of pile height length were focused between 9 mm and 9,5 mm length.
Discussion. Furthermore, when we analysed the results, pile height lengths were between 8 mm and 11,5 mm. The woven terry fabric production is a complicated process only on special looms that are equipped with the terry mechanism. This process allows the interlacement of warp and weft yarns some distance away from the actual cloth fell. Two series of warp threads, one for ground fabric and the other for pile, and one series of weft threads were required for terry fabric production in this process. The warp threads for the ground are kept under high tension while the warp threads for the pile are kept under low tension. For the pile warp threads were kept low tension, pile length was different from each other.
Conclusion. The first reason for the unevenness of pile height length, the linear density of warp and weft threads were more uneven. Secondly, the tension of threads leded to pile unevenness. If we use more even threads and made the balance of tension for the weaving towels possibly, then we can get more even pile towels.