Development of an Equation to Simulate Seam Pucker

  Introduction:  

Quality is one of the most sensitive and important factor in any industry. In Textile industry specifically in Garment Manufacturing it is one of the most concerned fields of domains being regularly focused. Everyday garment industry is defining as well as maintaining the quality through new methods.There are many issues in garment industry still remained unsolved or partially solved.

About Seam Pucker :

Seam pucker is considered to be one of them. Several research workers have made experimental study on the puckering problem of the seam .The detailed analysis has been also carried out to understand the factors governing the phenomenon and discussed further to eliminate the same in the products.

  About 20 factors are identified which have direct or indirect influences on seam pucker like needle and bobbin thread tension, fabric density i.e. picks per inch and ends per inch , yarn count, thread number, shrinkage of the both fabric and thread, weight of the fabric, SPI or stitch density, pressing force of the pressure foot, RPM of the machine etc. But still today it is widely controlled by operator’s skill during production and suggestions like, to lower the speed, adjusting the needle size and setting of bobbin thread tension, proper pressing force of the pressure foot are often utilized on trial and error basis.The aim of this research is to establish an equation which can prevent, generate or reproduce seam pucker along the seam line. In the present work with the controlled experimentation, attempts are made to generate variable set of seam pucker intensity in the fabrics. Then an equation has been developed in order that the amount of seam puckering can be predicted as well as prevented depending on the use of the equation during manufacturing. 

Different Parameters :

  we have selected five most prominent influential factors of seam puckering and three levels of the parameters are selected.

These are GSM of the fabric; RPM of the main shaft, Stitch per Inch Pressing force of the pressure foot and needle thread tension. Three levels of the parameters denote the range of them and the domain of the project against each of the parameters as well as the three levels also help to obtain curvilinear nature of the relationship between parameters and puckering intensity. Then total 729 polyester fabric samples having specific dimension are sewn to obtain varied level of seam puckering intensity measured by its length and thickness. With all these data we have derived the relation between the pucker intensity and five parameters based on the method of least squares. 

controlling or minimizing seam pucker :

Since there is no such definite formula or way to characterize seam pucker combining both contraction as well as the number of pucker’s wave, we have devised a new method by measuring the same following simple technique. We have observed a few phenomena during  projects.

For example the lightest fabric i.e. 70 gsm in our project seems to be very difficult to be sewn in 5000 RPM and above. Basically increasing in GSM, low ranges of speed around 3000 RPM, medium pressing force like 1.2 kg have been found to generate lower seam pucker. Again higher density of stitches and also thread tension with higher speed result in severe disturbance like needle breakage, fabric accumulation during light GSM fabric stitching. By analyzing the pucker intensity of 729 samples we have derived the equation by the method of least squares.

Conclusion : 

Ultimately we can predict the exact combination of the five parameters which will give the level of seam pucker intensity with the help of spread sheet program and Mat Lab. Further attempt is being made to use the method of design of experiment for 5 factors of three levels.

This project is limited in the domain of hundred percent polyester filament fabrics normally used for dress material. The study has therefore a practical implication in garment and related industries. Today in the world of fashion seam pucker is also considered as a different way to enhance the appearance of the garments. In such cases intensity of the puckering can be predetermined and regularized.

Keywords :

Seam pucker, pucker intensity, stitch density, RPM, GSM, pressing force, thread tension, Method of least squares

SEAM PUCKER