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Spunlacing is a promising nonwoven technology for the production of fabric with good handle and better structural integrity. Structural parameters such as pore size, thickness and number of binding point/entanglement between fibres are decisive for good mechanical and comfort properties of nonwoven fabrics. This study aims to focus on the effect of different process parameters on the structural change in spunlace fabrics.

Spunlacing is purely a mechanical bonding technology where high-speed jets of water strike a web to entangle the fibres. Different spunlace nonwoven structures were produced by varying processing parameters such as waterjet pressure, delivery speed, web mass and web composition as per four-factor, three-level Box–Behnken design. The effect of these parameters on the structural arrangement was studied using scanning electron microscopy. An attempt has also been made to study the changes in pore geometry and thickness of the fabrics by using response surface methodology with backward elimination.

Significant structural changes were observed with variation in water pressure, web mass and web composition. The test results showed that fabric produced at higher waterjet pressure has lower mean pore diameter and lower thickness. The variation in mean pore diameter and mean thickness due to waterjet pressure is around 26 and 34 per cent, respectively, at 95 per cent significance level. The web composition and web mass also significantly influence the mean pore diameter and thickness at 95 per cent significance level. There is a strong positive correlation (r = 0.523) between mean air permeability and mean pore diameter of fabric, and this correlation is significantly linear. A strong negative correlation (r = −0.627) is found between weight and air permeability of fabric.

The delivery speed failed to show any significant effect; this is in contrary to the general expectation.

The effect of concurrent variation in waterjet pressure, web mass, delivery speed and web composition on the structure of spunlace nonwoven is studied, which was not reported in the literature. The effect of web composition on pore diameter of spunlace nonwoven is interesting finding. This study is expected to help in designing the spunlace nonwoven as per end uses and specifically for apparel application.

An extremely high‐pressure jet of water is an efficient method of cutting soft materials, and combining the waterjet process with industrial robots is an economic alternative to the traditional punch tool method of producing complex‐shaped components for car interiors, such as floor carpets, headliners and door trims. Applications are given of robotic waterjet systems installed in the USA, France and Iran as well as news of a new cutting box introduced by ABB‐IR Waterjet Systems. A further development of the waterjet process is described in which the addition of abrasives enables aluminium castings to be fettled and cleaned.

This study aims at investigating the effect of bolt hole-making processes on the post-fire behavior of S235 steel plates.

A total of nine steel plates with a single bolt hole are tested. The single bolt holes are fabricated using three different hole-making processes: drilling, waterjet and plasma. Among the nine steel plates, three fabricated specimens are control specimens and are tested at ambient temperature. The six remaining steel plates with a single bolt hole are subjected to a complete heating-cooling cycle and then monotonically loaded until failure. The six fabricated specimens are first heated up to two different temperatures 800 and 925 °C, and then cooled back to the ambient prior to loading.

The results show that after being exposed to post-fire temperatures (800 and 925 °C), the maximum decrease in strength of the S235 steel plate was 6% (at 925 °C), 14% (at 925 °C) and 22% (at 800 °C) when compared to the results of ambient specimens for waterjet, drilled and plasma bolt holes, respectively. For post-fire temperature tests, drilled and waterjet bolt hole-making processes result in having approximately the same load-displacement response, and both have larger strength and ductility than those obtained using plasma cutting.

This study provides preliminary data to guide the steel designers and fabricators in choosing the most suitable hole-making process for fire applications and to quantify the post-fire reduction in capacity of S235 plates.

Outlines the background of robotized waterjet cutting and its advantages over traditional punching and manual cutting methods. Discusses the development of the modular cutting box which can be adapted to the customer’s requirements covering the water pressure, the size and speed of the jet, the reduction of sound emissions and a safety zone to protect personnel. Examines the programming of the robot arm and the creation of cutting programs. Concludes that waterjet cutting has enormous potential in the automotive industry.

The past five years have seen a significant improvement in the reliability and the acceptance of two‐dimensional abrasive waterjet (AWJ) cutting systems. Across all of the major industrial countries in Europe, one can now find any number of job shops or custom cutting centres offering AWJ cut parts. Three‐dimensional AWJ cutting systems were first introduced into the aerospace industry. The AWJ machines used to cut aerospace parts were mainly limited to large‐frame, cost‐intensive five‐axes units dedicated to the aerospace industry. Recently, a select few of the well‐established users of two‐dimensional AWJ cutting systems have acquired three‐dimensional AWJ cutting systems. New, lower‐priced systems combined with innovative configuration options, improved programming techniques, advanced automation and accuracy have taken three‐dimensional AWJ to another level. Discusses the recent developments in three‐dimensional AWJ systems.

Describes the technique of waterjet cutting and explains recent developments in the cutting head. Discusses the advantages of the new heads and gives typical parameter combinations for industrial applications.

Waterjet cutting is finding increasing use in the aerospace and motor industries. John Mortimer reports.

A pilot project at the Ford Motor Co. plant in Genk, Belgium, uses robot‐guided waterjets to cut holes in bumpers for Sierra cars.