Global shipments of electronic flat knitting machines soared by 99% in 2016 to around 139,600 machines, according to the latest figures from the International Textile Manufacturers Federation (ITMF).

Not surprisingly, the highest share of shipments were to Asia, accounting  for 94%, and China remained by far the world’s largest investor for flat knitting machines in 2016, with Chinese investments increasing from 35,500 units to 101,550 – a global share of 73%.

What the ITMF’s figures don’t show, however, is how many new flat knitting machines are now given over to the production of technical textiles, due to the emergence of a number of new end-use markets in recent years – from seamlessly knitted sports shoe uppers to multi-layered reinforcements for composites.

This made the Techtextil and Texprocess shows, which took place from May 9-12th, in Frankfurt, important for some machinery manufacturers who in the past may have primarily served the traditional apparel markets.

Seamless progress

“We exhibited our MACH2XS123 machine in 15L and SVR123SP in 14G at Techtextil, both drew crowds throughout the show interested in different aspects of knitting as a solution for technical textiles,” said Masaki Karasuno, creative director of the planning group for flat and seamless 3D knitting machinery specialist Shima Seiki, headquartered in Wakayama, Japan.

 “Visitors were of course, very interested in our WHOLEGARMENT technology and new developments specifically for  technical textile applications, such as the prototype exhibit of the elastic yarn tension control option on the MACH2XS, which was demonstrated knitting compression socks at the show.”

Other Shima-Seiki product samples exhibited related to sports and medical applications, as well as wearable technology.

“There was particular interest in the video presentation of custom-fit compression wear being produced from an initial 3D body scan performed on our original 3D body scanner,” said Karasuno. “The raw data is converted into programming data for a WHOLEGARMENT knitting machine on the SDS-ONE APEX3 3D design system. This can produce virtual samples of the product for evaluation before even having to knit an actual sample.”

Complex structures

Martin Legner, head of technical textile product management for Stoll, another flat knitting machinery leader, headquartered in Reutlingen, Germany, was equally enthusiastic.

“We unveiled our new cluster concept for applications in the sports, medical, home and mobility areas, along with the new CMS 330 HP W flat knitting machine, which is suitable for the manufacture of shoe uppers, orthopaedic supports, and textile accessories with complex shapes,” he said.

“No other manufacturing process for textiles combines complex structures, functionality and aesthetics as well as our flat knitting technology. Whether it’s for industrial applications or electrically-conductive textiles – the demand for which is increasing – flat knitting technology offers highly efficient, tailored solutions.”

The global apparel markets are currently very stable, he added, and while China has now slowed down its investments for this market to some extent after last year’s surge in deliveries, this is being compensated for by demand from other countries such as Bangladesh and Vietnam.

“Bangladesh is now a huge market and this has happened very quickly. But at the same time, technical textiles are becoming more and more important to Stoll and whereas, in the past, it was an area for two specialised sales divisions, it is now involving all of our sales force.”

Quality control

Automated quality control systems are of course, a must on such modern textile production technology, and BTSR, headquartered in Olgiate Olona, Italy, supplies to both the machinery builders and to individual mills.

“Our key products are yarn break sensors, yarn quality sensors and tension control feeders, along with our PC-Link Twist software solutions,” said sales and marketing manager Angelo Rizzo.

“The software is specifically aimed at the analysis of data concerning the count and control of yarn twists in yarn preparation processes and makes it easier to optimize the programming and monitoring of the quality control sensors installed on one or multiple machines. Our units add considerable value in yarn and weaving preparation processes, as well as hosiery, knitting and seamless machines,” he explained.

Reinforced concrete

Another new application for knitted fabrics was displayed on the stand of warp knitting systems specialist Karl Mayer – textile-reinforced concrete, which is poised to become the next main building material.

The weft-inserted, warp-knitted textiles for the reinforcement are produced on Karl Mayer’s machines to enable lightweight, narrow concrete components to be produced using tough, carbon-fibre grids.

Textile-reinforced concrete represents a valid lightweight alternative to conventional concrete with steel reinforcements, which are susceptible to corrosion and can lead to cracking and structural problems in today’s buildings.

Karl Mayer’s vice president of sales for technical textiles, Hagen Lotzman, observed that while glass fibre-based products remain the dominant market for multiaxial knitted reinforcements for composites – primarily for making wind blades – carbon fibre-based fabrics have become increasingly important over the past fifteen years. The company’s Cop Max 5 has rapidly become the standard technology for these.

“Carbon fibre is expensive, and initially, what was important was to minimise waste, while speed was not so critical,” he said. “As the industry progresses, however, output has become much more significant, and in many cases, quality control is much more important when it comes to aerospace and automotive applications where there are very strict requirements.

“For its standard configuration, the Cop Max 5 is equipped with a high standard of quality control and many sensors to ensure exact reproducibility.”

There is now a need for the whole composites manufacturing chain to work together to ensure the ultimate consideration is the final part, added product manager Swen Petrenz.

“Working together with customers, there’s a lot we can achieve in looking at the final contour of a part and considering the influence of drape and shape, and moving more towards near-net shape products. We come from roll goods and customers producing one material of a certain width and structure from the beginning of the roll to the end of it, but we’re moving far from that now.”

Live in Space

A Karl Mayer multiaxial knitted fabric made from carbon fibre was also among exhibits at the special Live in Space exhibition created by Messe Frankfurt in co-operation with ESA, the European Space Agency, and DLR, the German Aerospace Centre.

It featured an original Mars Rover and ESA and DLR space suits along with a host of other exhibits housed in a special lightweight pavilion.

This ‘Space Habitat’ consisted of 60 individual aluminium modules covered with a PTFE fabric specially designed by Swiss-headquartered textile architecture specialist MDT-tex to be extremely light weight, without sacrificing high temperature resistance.

Fabrics on display included warp-knitted metal mesh photovoltaic panels developed at RWTH Aachen in Germany and knitted spacers and multiaxials were also well represented.