The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Antonin Havelka - One of the best experts on this subject based on the ideXlab platform.
-
Effect of cyclic loading on the car seat’s seams
IOP Conference Series: Materials Science and Engineering, 2017Co-Authors: N Kovalova, J Geršak, Antonin HavelkaAbstract:The purpose of this work is to find out the influence of thread type, extension ratio and number of cycles to decrease in strength due to stress. In this study four different ratio of spun polyester and polyamide threads are used to sew the textile material (used for car seat cover) by a Lockstitch sewing machine. The measuring system simulation of cyclic load has been used. The tensile load, which corresponding to 20 %, 30 %, 40 %, and 50 % of the breaking extension of seam, acting on the experimental specimens with different type of was calculated. Based on the results of experimental measurements, which were closer to the real using conditions of seat covers, it can be stated that with increasing number of cycles, the strength due to the influence of the stress were decreased.
-
A study on DLC-coated industrial Lockstitch sewing needle
Industria Textila, 2015Co-Authors: Adnan Mazari, Antonin Havelka, Jakub Wiener, Zbigniew RozekAbstract:Diamond like carbon (DLC) coatings are well-known for the properties like protection against wear, low friction of coefficient and high hardness. In this research sewing needles are coated with DLC layer and then investigated for sewing performance. The results of the research shows that the needle temperature is decreased by nearly 9% at 4000 r/min of sewing and the breaking tenacity of stitched thread is nearly 6% higher as compared to the non-coated needles.
-
EXPERIMENTAL TECHNIQUES FOR MEASURING SEWING NEEDLE TEMPERATURE
Tekstil Ve Konfeksiyon, 2014Co-Authors: Adnan Mazari, Antonin HavelkaAbstract:In this article, three different methods (thermal camera, attached thermocouple and inserted thermocouple) are used to measure sewing needle temperatures on a Lockstitch machine. The experiments were conducted at machine speeds from 16 stitches/sec to 66 stitches/sec and for a maximum time of 60 seconds. This research is useful for predicting the real temperature of needles at different sewing speeds and for comparing methods of measurement. The inserted thermocouple method showed the lowest standard deviation and highly reproducible results. The results for all the measurement techniques are compared at different sewing speeds and will be beneficial for researchers who have made theoretical models for sewing needle temperatures and need to verify them using experimental results. The information in this article will also be useful for thread lubricant producers who use thermal cameras for needle temperature measurement. All of our experiments indicate that the needle temperature is always higher when thread is used, which is contradictory to the results of some researchers, who have found that needle temperature is lower when thread is used
-
Tensile Properties of Sewing Thread and Sewing Needle Temperature at Different Speed of Sewing Machine
Advanced Materials Research, 2012Co-Authors: Adnan Mazari, Antonin HavelkaAbstract:Needle heatup is a big issue for apparel industry especially for automobile industry seat covers where a lot of synthetic materials are used which get damaged by needle heat at high speed of sewing machine,in this article thermocamera and thermocouple are used to measure the precise temperature of needle eye and then 100% polyester 35x3 Tex thread is taken for sewing,the Lockstitch sewing machine is run at 1000rpm,2000rpm and 3000rpm respectively and the both methods are used to obtain the accurate needle temperature and finally thread tensile properties are measured before the sewing and taking out the thread from the seam precisely to get the tensile properties of thread after 10,30 and 60 seconds of continuous stitching,the article is very helpful in predicting the exact temperature of needle in lock stitch machine and getting the damage to thread by the needle heat at different speeds and different stages of sewing process.
-
Needle eye temperature measurement at different speeds of sewing
2012 International Conference on Engineering and Technology (ICET), 2012Co-Authors: Adnan Mazari, Antonin Havelka, Funda Buyuk MazariAbstract:In this article two methods are used to measure the temperature of needle eye during the high speed of sewing and the results are compared for calculating the precision in the measurement, Needle heatup is a big issue for apparel industry especially for automobile industry seat covers where a lot of synthetic materials are used which get damaged by needle heat at high speed of sewing machine, in this article thermocamera and thermocouple are used to calculate the precise temperature of needle eye and then 100% polyester 35×3 Tex thread is taken for sewing, the Lockstitch sewing machine is run at 1000rpm, 2000rpm and 3000rpm respectively and the both methods are used to obtain the accurate needle temperature and finally thread tensile properties the article is very helpful in predicting the exact temperature of needle in lock stitch machine at different stages of sewing process.
Arunangshu Mukhopadhyay - One of the best experts on this subject based on the ideXlab platform.
-
Impact of Positive Thread Feeding for High-Speed Industrial Lockstitch Sewing Machines: Part II Response with Cotton and Spun Polyester Needle Threads
Journal of The Institution of Engineers (India): Series E, 2019Co-Authors: Vinay Kumar Midha, Vaibhav Gupta, Arunangshu MukhopadhyayAbstract:During high-speed industrial Lockstitch sewing, the dynamic, thermal, bending and abrasive loading of the thread has a negative influence on the tensile properties of sewing threads. For maximum strength retention of needle thread, a positive thread feeding device is developed which lowers the stitch tightening tension (or peak tensions). Two types of threads, viz. mercerised cotton and spun polyester threads of linear density 40 tex and 60 tex, are taken for investigation. During conventional sewing, there is a significant loss in breaking force and elongation for cotton and spun polyester threads. It is observed that loss in breaking force is significantly lower with positive thread feeding device as compared to conventional sewing, whereas loss in breaking elongation is significantly lower in most of the cases for both cotton and spun polyester threads. The peak tensions observed during sewing with positive thread feeding device are much lower than the conventional sewing. The loss in breaking force and elongation for the cotton threads during sewing is higher than that of spun polyester threads in the case of both conventional sewing and sewing with positive thread feeding device. In both the cases, coarser threads show higher loss in breaking force and breaking elongation during sewing as compared to finer threads. During conventional sewing, the initial modulus of cotton threads decreases significantly, while there is a significant gain in initial modulus of spun polyester threads. With positive thread feeding device, there is a significant improvement in initial modulus for cotton and spun polyester threads.
-
Impact of Positive Thread Feeding for High-Speed Industrial Lockstitch Sewing Machines: Part I Development of Device
Journal of The Institution of Engineers (India): Series E, 2019Co-Authors: Vinay Kumar Midha, Vaibhav Gupta, Arunangshu MukhopadhyayAbstract:During high-speed industrial Lockstitch sewing, repeated stresses and strains on the needle thread adversely influence its sewing performance. The sewing performance of threads is affected by reduction in its tensile strength. For maximum strength retention of needle thread, a positive thread feeding device is developed, which is independent of the fabric feed mechanism as in conventional sewing, where sewing thread is pulled from the cone directly wherein the thread feed is controlled by spring disc tensioner and needle movement. The dynamic needle thread tension is measured above the needle bar using strain gauge load cell. The load cell converts force or weight into electrical signal. The highest thread tension (stitch tightening tension) occurs when the take-up lever pulls the required thread amount through the spring disc tensioner. Positive thread feeding of needle thread lowers the tightening tension (peak tension), and hence, strength retention of needle thread is observed. In this paper, the breaking force of mercerized cotton needle thread at various sewing variables, viz. fabric density, number of fabric layers, and stitch length, is studied during conventional sewing and also by using positive thread feeding device. The loss in breaking force increases with the increase in fabric density, whereas it decreases as the number of fabric layers and stitch length increased.
-
Studies on the Changes in Tensile Properties of Sewing Thread at Different Sewing Stages
Textile Research Journal, 2009Co-Authors: Vinay Kumar Midha, Arunangshu Mukhopadhyay, R. Chatopadhyay, V. K. KothariAbstract:A Lockstitch is formed by the interlacement of needle and bobbin threads. During high-speed sewing, needle thread is subjected to repeated tensile stresses, heat, bending, pressure, torsion, and wearing. Therefore, the mechanical properties of thread, which become altered during sewing, are very important for its performance and durability. In order to design a sewing machine and threads for maximum strength retention, it is important to understand how the mechanical properties of the thread change as it progresses through the machine and become incorporated into the seam. In this paper, the tensile properties of the needle thread are measured at four sewing stages: before sewing, after dynamic loading at the tension regulator, after passage through the needle and fabric, and after bobbin thread interaction. Mercerized cotton, polyester staple spun, polyester—cotton core spun, and polyester—polyester core spun threads are used and the contribution of dynamic loading, passage through the needle and fabric,...
Adnan Mazari - One of the best experts on this subject based on the ideXlab platform.
-
A study on DLC-coated industrial Lockstitch sewing needle
Industria Textila, 2015Co-Authors: Adnan Mazari, Antonin Havelka, Jakub Wiener, Zbigniew RozekAbstract:Diamond like carbon (DLC) coatings are well-known for the properties like protection against wear, low friction of coefficient and high hardness. In this research sewing needles are coated with DLC layer and then investigated for sewing performance. The results of the research shows that the needle temperature is decreased by nearly 9% at 4000 r/min of sewing and the breaking tenacity of stitched thread is nearly 6% higher as compared to the non-coated needles.
-
EXPERIMENTAL TECHNIQUES FOR MEASURING SEWING NEEDLE TEMPERATURE
Tekstil Ve Konfeksiyon, 2014Co-Authors: Adnan Mazari, Antonin HavelkaAbstract:In this article, three different methods (thermal camera, attached thermocouple and inserted thermocouple) are used to measure sewing needle temperatures on a Lockstitch machine. The experiments were conducted at machine speeds from 16 stitches/sec to 66 stitches/sec and for a maximum time of 60 seconds. This research is useful for predicting the real temperature of needles at different sewing speeds and for comparing methods of measurement. The inserted thermocouple method showed the lowest standard deviation and highly reproducible results. The results for all the measurement techniques are compared at different sewing speeds and will be beneficial for researchers who have made theoretical models for sewing needle temperatures and need to verify them using experimental results. The information in this article will also be useful for thread lubricant producers who use thermal cameras for needle temperature measurement. All of our experiments indicate that the needle temperature is always higher when thread is used, which is contradictory to the results of some researchers, who have found that needle temperature is lower when thread is used
-
Tensile Properties of Sewing Thread and Sewing Needle Temperature at Different Speed of Sewing Machine
Advanced Materials Research, 2012Co-Authors: Adnan Mazari, Antonin HavelkaAbstract:Needle heatup is a big issue for apparel industry especially for automobile industry seat covers where a lot of synthetic materials are used which get damaged by needle heat at high speed of sewing machine,in this article thermocamera and thermocouple are used to measure the precise temperature of needle eye and then 100% polyester 35x3 Tex thread is taken for sewing,the Lockstitch sewing machine is run at 1000rpm,2000rpm and 3000rpm respectively and the both methods are used to obtain the accurate needle temperature and finally thread tensile properties are measured before the sewing and taking out the thread from the seam precisely to get the tensile properties of thread after 10,30 and 60 seconds of continuous stitching,the article is very helpful in predicting the exact temperature of needle in lock stitch machine and getting the damage to thread by the needle heat at different speeds and different stages of sewing process.
-
Needle eye temperature measurement at different speeds of sewing
2012 International Conference on Engineering and Technology (ICET), 2012Co-Authors: Adnan Mazari, Antonin Havelka, Funda Buyuk MazariAbstract:In this article two methods are used to measure the temperature of needle eye during the high speed of sewing and the results are compared for calculating the precision in the measurement, Needle heatup is a big issue for apparel industry especially for automobile industry seat covers where a lot of synthetic materials are used which get damaged by needle heat at high speed of sewing machine, in this article thermocamera and thermocouple are used to calculate the precise temperature of needle eye and then 100% polyester 35×3 Tex thread is taken for sewing, the Lockstitch sewing machine is run at 1000rpm, 2000rpm and 3000rpm respectively and the both methods are used to obtain the accurate needle temperature and finally thread tensile properties the article is very helpful in predicting the exact temperature of needle in lock stitch machine at different stages of sewing process.
K R Salhotra - One of the best experts on this subject based on the ideXlab platform.
-
strength reduction in sewing threads during high speed sewing in industrial Lockstitch machine part ii effect of thread and fabric properties
International Journal of Clothing Science and Technology, 1998Co-Authors: G Sundaresan, K R Salhotra, P K HariAbstract:The mechanism of strength reduction of sewing threads has been discussed in Part I of this paper. The effect of fabric tightness and certain thread properties like its size, coefficient of yarn‐metal friction, twist direction, number of piles, type of fibre and fibre denier on strength reduction has been studied and found to influence the severity of strength reduction of the thread.
-
strength reduction in and damage to fibres during high speed sewing in an industrial Lockstitch machine
Journal of The Textile Institute, 1998Co-Authors: G Sundaresan, P K Hari, K R SalhotraAbstract:The reduction in the tensile strength of polyester fibres on sewing is studied for threads with different yarn and fibre linear density and tenacity. The strength loss ranges between 4.8% and 8.9% and is much less than that of the sewn threads. The initial modulus of the fibre and the extent of loading during sewing influence the strength reduction. A scanning-electron-microscope (SEM) study of sewn threads and of the constituent fibres shows that the damage is mostly concentrated at the interlacing point of the needle thread in the stitch. Among the various stresses acting on the fibres, bending and surface abrasion are found to be more dominant in causing damage to tbe fibre.
-
strength reduction of sewing threads during high speed sewing in an industrial Lockstitch machine
International Journal of Clothing Science and Technology, 1997Co-Authors: G Sundaresan, P K Hari, K R SalhotraAbstract:Reports on investigations into the mechanism of sewing thread strength reduction. Results indicate that structural damage, namely, structural openness and pull‐out of fibre ends from the surface are the major cause of strength reduction and that the fibre strength reduction is found to be only marginal compared to the thread strength reduction. Cotton threads exhibit higher strength loss owing to their poor abrasion resistance. Comparatively shorter fibres in cotton threads are also found to be responsible for the higher strength reduction.
Vaibhav Gupta - One of the best experts on this subject based on the ideXlab platform.
-
Impact of Positive Thread Feeding for High-Speed Industrial Lockstitch Sewing Machines: Part II Response with Cotton and Spun Polyester Needle Threads
Journal of The Institution of Engineers (India): Series E, 2019Co-Authors: Vinay Kumar Midha, Vaibhav Gupta, Arunangshu MukhopadhyayAbstract:During high-speed industrial Lockstitch sewing, the dynamic, thermal, bending and abrasive loading of the thread has a negative influence on the tensile properties of sewing threads. For maximum strength retention of needle thread, a positive thread feeding device is developed which lowers the stitch tightening tension (or peak tensions). Two types of threads, viz. mercerised cotton and spun polyester threads of linear density 40 tex and 60 tex, are taken for investigation. During conventional sewing, there is a significant loss in breaking force and elongation for cotton and spun polyester threads. It is observed that loss in breaking force is significantly lower with positive thread feeding device as compared to conventional sewing, whereas loss in breaking elongation is significantly lower in most of the cases for both cotton and spun polyester threads. The peak tensions observed during sewing with positive thread feeding device are much lower than the conventional sewing. The loss in breaking force and elongation for the cotton threads during sewing is higher than that of spun polyester threads in the case of both conventional sewing and sewing with positive thread feeding device. In both the cases, coarser threads show higher loss in breaking force and breaking elongation during sewing as compared to finer threads. During conventional sewing, the initial modulus of cotton threads decreases significantly, while there is a significant gain in initial modulus of spun polyester threads. With positive thread feeding device, there is a significant improvement in initial modulus for cotton and spun polyester threads.
-
Impact of Positive Thread Feeding for High-Speed Industrial Lockstitch Sewing Machines: Part I Development of Device
Journal of The Institution of Engineers (India): Series E, 2019Co-Authors: Vinay Kumar Midha, Vaibhav Gupta, Arunangshu MukhopadhyayAbstract:During high-speed industrial Lockstitch sewing, repeated stresses and strains on the needle thread adversely influence its sewing performance. The sewing performance of threads is affected by reduction in its tensile strength. For maximum strength retention of needle thread, a positive thread feeding device is developed, which is independent of the fabric feed mechanism as in conventional sewing, where sewing thread is pulled from the cone directly wherein the thread feed is controlled by spring disc tensioner and needle movement. The dynamic needle thread tension is measured above the needle bar using strain gauge load cell. The load cell converts force or weight into electrical signal. The highest thread tension (stitch tightening tension) occurs when the take-up lever pulls the required thread amount through the spring disc tensioner. Positive thread feeding of needle thread lowers the tightening tension (peak tension), and hence, strength retention of needle thread is observed. In this paper, the breaking force of mercerized cotton needle thread at various sewing variables, viz. fabric density, number of fabric layers, and stitch length, is studied during conventional sewing and also by using positive thread feeding device. The loss in breaking force increases with the increase in fabric density, whereas it decreases as the number of fabric layers and stitch length increased.
-
predicting sewing thread consumption for Lockstitch using regression model
Research journal of textile and apparel, 2016Co-Authors: Vinay Kumar Midha, Shailja Sharma, Vaibhav GuptaAbstract:Purpose This paper aims to develop a single regression model (instead of developing models separately for each thread type) to predict the sewing thread consumption for cotton and polyester staple spun threads. Design/methodology/approach A single regression model is developed for predicting sewing thread consumption for cotton and polyester threads. The polyester sewing threads have lower sewing thread consumption as compared to cotton threads because of their higher elongation behaviour. The model differentiates between the cotton and polyester sewing threads using their elongation values at peak levels of tensions experienced by the sewing threads during stitch tightening. By comparing the estimated thread consumption values with actual values, the effectiveness of model is evaluated with root mean square error and coefficient of determination (R2). Findings During the sewing process, by understanding the behaviour of different types of sewing threads, it is possible to develop a single regression model for all types of threads. Practical implications The sewing thread consumption can be easily calculated for cotton and polyester sewing threads using a single regression equation using the sewing assembly thickness, stitch density and elongation of thread at peak tension. The garment manufacturers need not depend on different charts for sewing thread consumption for stock management. Originality/value The sewing thread consumption is different for different types of threads, and garment manufacturers have to depend on different charts given by sewing thread manufacturers or use different equations for each type of threads. Using this single regression equation, sewing thread consumption for cotton and polyester sewing thread can be estimated accurately.
