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The purpose of this paper is to investigate the factors effecting ultrasonic seam tensile properties.

In this study, 100 percent polypropylene and 100 percent polyester spunbond and meltblown nonwoven fabrics were sewn by using ultrasonic sewing machine with different rollers which have two, three and four rows. Seam tensile properties of the sewn nonwoven fabrics were investigated. Four-Level Nested Anova Design was applied to the data by using Minitab 15 software program.

Higher seam strength values were obtained by using four rows roller, PP fiber, spunbond fabric and 50 g/m2 fabric area density for all nonwoven fabrics. Statistical significance was found between fabric area density, roller rows and seam tensile strength properties and between fabric type, roller rows and seam elongation at break values.

When the authors look at the studies related to ultrasonic sewing, several researchers studied on welding parameters of ultrasonic sewing but very limited studies were performed on assembling of nonwoven fabrics with ultrasonic sewing. Therefore effect of production methods of nonwoven fabrics on the properties of ultrasonic sewing such as seam strength and elongation at break should be investigated.

Surgical gowns should be designed and produced using special techniques to provide barrier properties against potential risks during surgery and healthcare procedures. Ultrasonic welding is one of these methods used to produce surgical gowns with determined barrier properties. The purpose of this paper is to analyse bond strength and permeability properties of ultrasonically welded nonwoven fabrics and compare them with traditional sewing techniques.

In this study, ultrasonic welding of nonwovens was performed to demonstrate its use as an assembly method. Performance requirements in the design of surgical gowns were determined. Fabric strengths and bond strengths of ultrasonic-welded and traditionally sewn fabrics were analysed. The performance properties, i.e., bond strength, air and water resistance of the fabrics and the joints obtained by ultrasonic and classical sewing methods were studied.

As a result, it was found that ultrasonic welding technique is a suitable method for joining layers in surgical gown production bringing the advantages of high water resistance together with acceptable bond strength.

The current study focuses on the use of ultrasonic welding of nonwovens used for disposable protective surgical gowns. Ultrasound welding technique was presented as an alternative to classic assembly methods and ultrasonic welding technology was applied to different fabric combinations simulating different layers in different joining sections of a surgical gown.

Ultrasonic seaming: the pertained technology for this research is identified as one of the alternatives which offers many advantages over traditional sewing. Ultrasonic technology was initially used for plastic welding. It has been utilized in automotive, electronics and electrical appliances, filtration, packaging, aerospace and apparel industries. However, the use of sewing machine, needle and threads still remains as the most popular method of joining fabrics together. The aim of this research is to investigate the possibility of constructing different types of seams for clothing using ultrasonic technology which is an existing technology that is not fully utilized and not fully realized the advantages associated with it in the apparel industry.

Experimental reflective practice' was used as the main method for practical investigation. The basis for analysis was formed by reflections made during and after the experimentations.

Though the construction of the seams are possible, due to thickness of the layers, LSc and LSe seam types were not successful in terms of quality. The bound seam type and the flat seams are possible using ultrasonic technology without the blade, the quality is not satisfactory when comparing to the conventional sewing technique. However, ornamental stitching (OS) and edge finishing (EF) with ultrasonic are possible and successful.

The results of this study will shed more light on ways of using ultrasonic technology in the apparel industry.

Investigates the potential for building smart seams by incorporating optic fibers ultrasonically. The heating and bonding mechanisms of ultrasonic welding process in fabrics were studied. Battle dress uniform (BDU) (50/50 nylon/cotton), 100 percent cotton, 100 percent polyester and Nomex fabrics were used and were bonded ultrasonically with and without polyurethane adhesives. The effects of three important welding parameters, namely weld pressure, weld time and amplitude of vibration, on the joint strength and the temperature profile at the interface were examined. The temperature profiles for different fabrics were measured during ultrasonic welding process. The attenuation degree of signal transition properties of optic fibers incorporated was tested to determine if ultrasonic process provided a possible way of embedding optic fibers into seams and achieving sufficient joint strength while the signal transmission properties of optic fibers incorporated were not changed significantly.

Examines, through an empirical survey, the nature of the relationships between buyer and subcontractor firms in the clothing industry in Italy. Starting from the identification of three classes of buyer firms (characterized by the different ways in which they relate to the market), develops an interpretive framework of firms’ strategies in managing subcontractor relationships. Shows that the buyer‐subcontractor relationship is undergoing a drastic evolution with the strategic importance of an “extended integrated production system” being recognized. Discusses how this ongoing evolutionary process is involving firms in different ways: the shift to an evolved buyer‐supplier relationship (characterized by a logic of integration/co‐operation), seems to concern only one of three classes of firm defined.

The present paper aims to demonstrate the potential of integration between industrial robotics and Lean Manufacturing (LM) approach to increase the efficiency of an assembly line.

Based on a case study performed in an Italian company, this paper reports a comparative analysis of the results produced on a line balancing study involving a semi-automated production line, aided by an industrial robot.

The results suggest the possibility of implementing industrial robotics in line balancing studies highlighting efficiency gains and idle reduction. Further, it also addresses some concepts directly related to industry 4.0, such as collaborative robotics, artificial intelligence, and lean automation.

Line balancing studies may include advanced robotics in order to extend traditional lean practices toward Digital LM.

This study adds contributions to the operational excellence literature, demonstrating the symbiosis between industrial robotics and LM practices.

Today when the newest high‐tech fibers and sophisticated material constructions are used for the production of sails, forming 3D sail shape from 2D sailcloth has still remained very primitive because classic sewing techniques are mostly used. Since, the clothing and technical textile industry has been recently using some of contemporary joining techniques (ultrasonic, thermal, high‐frequency) replacing classic sewing, this paper seeks to investigate the possibility of ultrasonic welding in the production of sails, and the strength of obtained bonds.

Concerning the aim, sails were made employing the classic and modern (ultrasonic) joining technique whereby bonding parameters such as amplitude and welding speed, geometry of anvil wheels were varied. Objective quality evaluation of the bond made in such a way, was performed in order to be more exact about its strength.

Based on the obtained results it has been concluded that ultrasonic welding may successfully replace the classic sewing of sails, selecting an anvil wheel with suitable engraving and optimal parameters of welding (speed and amplitude).

Selection of optimal welding parameters not only increases the sail's bond strength in comparison with classic seam, but also provides sail air impermeability, being one of the basic aerodynamic requirements for sail making.

This paper has presented the novel and successful approach in 3D sail shape forming from 2D sailcloth.

Seam pucker is one of the most important aspects of garment quality in the sewing process. Recently, automatic sewing systems have been developed and seam pucker or other defects would have to be automatically inspected in these systems. Two systems of automatic, contactless measurement of seam pucker have been developed. One of the measurement systems, with which surface shape of seam pucker was measured, is based on laser technology. Intensity of reflected ultrasonic wave is measured using another measurement system. The laser measurement system has been applied to moderate or severe seam pucker and the ultrasonic wave system has been applied to the accurate evaluation of very small seam pucker. The result of the evaluation by machine has to match the result of subjective evaluation by humans. To verify this, samples of seam pucker were evaluated using five judges. With the measurement data of surface shape of these samples, the power spectra of the wave form of seam pucker are calculated. Analyses and correlates the relationship between objective measurement and subjective evaluation by discriminant analysis, with the result of subjective evaluation and the power spectra of the samples. Having obtained these relationships, the degree of seam pucker can be measured objectively by both systems.

An improved waterproof seam production technology (ultrasonic welding-thermo adhesive tape sealing (USW-TATS)) was developed in this study. The technology will improve the waterproof performance of seam which has problem resulted from needle holes and thread like seam leaking and excess shrinkage.

Threadless seams were produced by ultrasonic welding (USW) with coated and lamination fabric to replace the traditional sewing process in Sewing-thermo adhesive tape sealing (S-TATS). The process efficiency was evaluated by Methods-Time Measurement (MTM). Seam performance including hydrostatic pressure, shrinkage and tear force was compared among three technologies (USW, USW-TATS and S-TATS). The effect of ultrasonic welding parameters (amplitude, roller pressure and roller speed) on the USW-TATS seam performance was investigated.SEM analysis was carried out to examine the condition and morphology of the joints cross section.

It was found that waterproof performance and dimensional stability of USW-TATS seam were superior to that of S-TATS seam. Tear force and hydrostatic pressure increased firstly and then decreased with the increasing of USW parameters in UAW-TATS process. Binary regression relationships were found between the USW parameters and tear force or hydrostatic pressure. Shrinkage decreased with the increasing of roller pressure and speed.

Research results can be applied to predict seam performance of waterproof clothing, reduce equipment parameters setting time and enhance product quality in industry.

A threadless production technology (USW-TATS) was proposed to improve waterproof performance and dimensional stability of outdoor clothing seams.

Ultrasonic welding is an emerging apparel manufacturing technique. However, the applications are widely explored in the field of technical textiles, with less exploration in the apparel endues. The purpose of this study is to explore the application of ultrasonic welding in apparel by analyzing the impacts of different parameters.

This study analyzed the influence of ultrasonic welding parameters, including pressure, welding speed and ultrasonic power on the seam performances (seam strength, seam bursting strength, seam thickness and seam stiffness). The parameters are optimized using Box–Behnken experimental design to achieve better seam performances.

The properties of ultrasonic seams are influenced by welding and fabric properties. Ultrasonically welded seams showed better performances in the case of comfort properties of seams, whereas the functional properties are lesser compared to conventional seams.

The findings of the research clearly outline the level of influence of different parameters on the performance of the ultrasonically welded seams in knitted fabrics, which can greatly help in applying ultrasonic welding manufacturing methods in apparel manufacturing.