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The most widely recycled plastic in the world is recycled polyethylene terephthalate (rPET). To minimize the environmental related issues associated with synthetic fibers, several researchers have explored the potential use of recycled polyester fibers in developing various technical textile products. This study aims to develop needle-punched nonwoven fabrics from recycled polyester fibers and investigate its suitability in oil spill cleanup process.

According to Box and Behnken factorial design, 15 different needle-punched nonwoven fabrics from recycled polyester fibers were prepared by changing the parameters, namely, needle punch density, needle penetration depth and fabric areal weight. Several featured parameters such as oil sorption, oil retention, oil sorption kinetics, wettability and reusability performance were systematically elucidated.

The maximum oil sorption of recycled nonwoven polyester is found to be 24.85 g/g and 20.58 g/g for crude oil and vegetable oil, respectively. The oil retention is about 93%–96% in case of crude oil, whereas 87%–91% in case of vegetable oil. Recycled polyester nonwoven possesses good hydrophobic–oleophilic properties with static contact angle of 138° against water, whereas 0° against crude oil and vegetable oil. The reusability test results indicate that recycled polyester nonwoven fabric can be used several times because of its reusability features.

There is no detailed study on the oil sorption features of needle-punched nonwoven fabrics developed from recycled polyester fibers. This study is expected to help in developing fabrics for oil spill cleanups.

This paper presents an experimental study on needle heating in sewing heavy materials such as upholstery fabrics. In the experiments, infrared (IR) radiometry, high speed line scanning IR radiometry, and high speed IR radiometry are used to obtain thermal images of the needle during sewing. In particular, IR radiometry was used in lower speed sewing (approximately 500rpm). High speed IR and high speed line scanning IR radiometry were used for medium speed sewing (1,000‐2,000rpm). Using Taguchi’s design of experiment method, the effects of various factors are studied including needle conditions (sharp or blunt), sewing speeds, number of stitches per inch, material being sewn, and thread tension. It is found that even with air vortex cooling the needle may still reach high enough temperatures that may affect the sewing quality and even cause thread breakage. This was confirmed via a thread tensile testing experiment. An empirical model of the mean needle temperature is also proposed and tested.

“V-bending” is the most commonly used bending process in which the sheet metal is pressed into a “V-shaped” die using a “V-shaped” punch to form a required angular bend. When the punch is removed after the operation, because of elastic recovery, the bent angle varies. This shape discrepancy is known as spring back which causes problems in the assembly of the component in the modern aerospace industry. Regarding the optimization of spring-back accuracy, this research will illustrate the laws of the transition area (TA) of the nondeformation area (NDA) during the 90° “V-shape” bending process.

According to the traditional “V-bending” process to optimize the spring-back accuracy, the bent sheets are divided into deformation area (DA) and NDA. For this reason, the traditional “V-bending” process may prolong error to optimize the spring-back accuracy because NDA has a certain amount of deformation, which the researcher always avoids. Firstly, bent sheets are divided into three parts in this research: DA, TA and NDA to avoid the distortion error in TA that are not considered in the NDA in traditional theory. Then, the stress and strain in the DA and TA were discussed during theoretical derivation and some hypotheses were proposed. In this research, the interval, position and distortion degree of the TA of the bending sheet are used by finite element analysis. Finally, V-shape bending tests for aluminum alloy at room temperature are used and labeled all the work pieces' TAs to realize the deformation amount in the TA.

The bending radius does not affect the range of the TA, it only changes the position of TA in the bending sheet. It is evident that the laws of TA were explored in the width direction and gradually changed from the inner layer to the outer layer based on the ratio of width and thickness of the bending plate/sheet.

In the modern aerospace industry, aircraft manufacturing technology must maintain high accuracy. This research has practical value in the 90° “V-shape” bending of metal sheets and the development of its spring-back accuracy.

The purpose of this paper is to propose a theoretical model to predict the mechanical behaviour of needle punched heavy geotextiles in uniaxial tensile test.

The model was constructed using theory of layered composite materials and finite element method. The properties of a reference fabric were used as initial data in theoretical calculations and a commercially available finite element program was chosen to carry out stress analysis. A comparison is made between theoretical calculations and experimental data to evaluate the deformation mechanism of geotextile fabrics in uniaxial tensile test.

The results indicate that compatible data were predicted in terms of stress values and stress distribution of fabrics. The inconstant lateral contraction of nonwoven fabrics in tensile test is also successfully simulated by the model. However, in the case of elongations, the model could not predict the strains of heavy geotextiles accurately.

The study aims at predicting the mechanical behaviour of needle punched heavy geotextiles by using the structural and mechanical properties of a “reference fabric” instead of constituent fiber properties.

The purpose of this paper is to investigate the acoustic properties of needle-punched nonwovens produced of bamboo, banana and hemp fibers blended with polyester (PET) and polypropylene (PP) as they are supportive enough to minimize sound transmission inside the automobiles.

Textile materials like bamboo, banana and hemp blended with PET and PP in the ratio of 35:35:30 were applied to make the web. The needle-punching technique was applied to each web for three times to form a full nonwoven textile composite. The concept of PET/PP blend with natural fibers was to enhance the consistency and thermoform propensity of the composites. When nonwoven textile composites were placed in between a sound source and a receiver, they absorbed annoying sound by dissolving sound wave energy. Sound absorption coefficient was measured by the impedance tube method as per ASTM C384 Standard. Bamboo/PET/PP composite showed the highest absorption coefficient in most of the frequencies.

Physical and comfort properties were tested for the composites and it was noticed that bamboo/PET/PP composites with its compressed structure showed a better stiffness value, lesser thermal conductivity, lesser air permeability, better absorption coefficient and highest sound transmission loss compared to other two composites. At 840 Hz, the absorption coefficient of bamboo/PET/PP remained in satisfactory level but it was inferior by 20 percent in banana/PET/PP. Conversely at more frequencies like 1,680 Hz, there was a decrease from the target level in all the nonwovens composites, which could be enhanced by raising the thickness of the nonwovens, and all these properties of bamboo/PET/PP were considered appropriate for controlling noise inside the vehicles.

This research will provide facilities to decrease noise inside the vehicles. It will improve the apparent value of the automobiles to the traveler and also provide a sensible goodwill to the manufacturer.

This research will open several ways for the development of different nonwoven composites, particularly for the sound absorption and will open possible ways for the scholars to further study in this field.

The purpose of this study is to investigate the effect of punching on the local magnetic properties of the nonoriented electrical steel sheet.

A microcomposite B–H sensor consisting of a pair of B probes with a spacing of 2 mm and a 1.8 × 1.8 mm² H coil is designed. The region and degree of local magnetic properties degradation caused by punching can be quantitatively analyzed by flexibly moving the composite B–H sensor. The influence and physical mechanism of punching on the hysteresis loss, eddy current loss and excess loss are analyzed based on the Bertotti loss separation theory.

This study investigates the deterioration effect of the punched nonoriented electrical steel. The permeability near the edge decreases, and the core loss as well as the microhardness increases. The region of magnetic property deterioration is dependent on the area of work hardening.

The microcomposite B–H sensor can be used to measure the magnetic properties near the edge of electrical steel sheets under different processing conditions. This study provides the possibility of precise magnetic property model of the motor core after punching, especially valuable for motors without annealing process.

I first met punched feature cards in 1956. I was working as an assistant to E. G. Brisch, whose company classified the materials and components used in industry. His method brought similar articles together, both notionally in classified codebooks and practically when the classified items were stored in their code number order. The result was an excellent aid to variety reduction, standardization, and stock control. E. G. gave me a good grounding in analytical classification; but his office held other secrets too. One of these was a sort of punched card representing a property or quality, not an object or event as with all other punched cards I had met. On these other cards, notched or slotted for hand‐sorting with needles, or punched and verified in thousands for reading by machine, the holes stood for characteristics possessed by the item concerned. The new cards were different. Since they represented properties, the items possessing these had to be shown by the holes, and so they were. E. G. named them ‘Brisch‐a‐boo’: this I found was his special variant of ‘peek‐a‐boo’, a title by which they are still occasionally known. To stack some of them in exact register with each other is to find, as a set of through holes in numbered positions, the reference numbers of all the items recorded on them which have the qualities concerned.

This is the second part of our study on needle heating in heavy industrial sewing. In this part, a finite element analysis (FEA) model is presented. Using a commercial FEA software system, ANSYS, the needle is modeled by a number of 3D bar elements and the sewing process is modeled by a series of time and space dependent boundary conditions. The model considers various important factors such as the needle geometry (including the point angle and point length of the needle), the friction between the needle and the fabric, the friction between the needle eye and the thread, the fabrics’ material property, and the sewing conditions. It can predict needle heating in high accuracy. In order to validate the model, a large number of experiments were conducted, in which the needle temperatures were measured using infrared radiometry. It is found that the simulation results match the experiment results very well. Finally, a number of suggestions to reduce the needle heating are presented.

This paper aims to investigate on composite fabrics to develop the improved sleeping bag using trilayered textile structures. A thermal comfort analysis of fabrics is essential to design an enhanced type of sleeping bag.

In this study, optimizing thermal and permeability properties of different combinations of trilayer composite fabrics was done. The inner layer was 100% wool-knitted single jersey fabric. The middle layer was polyester needle punched non-woven fabric. The outermost layer was nylon-based Core-Tex branded waterproof breathable fabric. Five variations in wool-knitted samples were developed by changing the loop length and yarn count to optimize the best possible combination. Two different polyester non-woven fabrics have been produced with the changes in bulk density. Twelve trilayer composite fabric samples have been produced, and thermal comfort properties such as thermal conductivity, thermal absorptivity, thermal resistance, air permeability and relative water vapour permeability have been analysed.

Among the 12 samples, one optimized sample has been found with the specification of 100% wool with 25 Tex yarn linear density having 4.432-mm loop length inner-layered fabric, 96 g/m² polyester nonwoven fabric as the middle layer, and 220 g/m² Nylon-Core tex branded outermost layer. All the functional properties of the composite fabric are significantly different with the knitted wool fabrics and polyester nonwoven fabrics, which have been confirmed by analysis of variance study.

This research work supports for producing sleeping bag with enhanced comfort level.

At six‐weekly intervals The British Iron and Steel Research Association issues a Report List containing abstracts of and references to its research reports. One list may contain between 25 and 50 abstracts. A classification system for these references is very necessary for the Association's Information Section. The system that has been used for the past seven years consists of a subject and author index and has grown and been amended so often that it has gradually become more unworkable as the diversity of our research work has increased.