The development and future of circular knitted fabric.
Relative movement technology -
today's single jersey standard.
One of the underlying characteristics of the circular knitting principle has always been high productivity, due largely to the decisive advantages of short setting times and a continuous circular movement. With demand for ever increasing speeds, however, naturally enough the time came when knitting machines had reached their mechanical limitations.
A particular problem here is the number of deflection points for the yarn and the associated stress on the thread in the stitch forming zone. Logically enough, each deflection of the thread creates friction, and the overall degree of stress on the yarn depends primarily upon the number of yarn deflection points. As a result, the choice of yarn quality was determined not only by the targeted fabric quality, but also by the breaking resistance of the yarn.
The yarn - the major cost factor in circular knitting.
A technically sophisticated single jersey circular knitting machine today processes yarn quantities with a market value of over 500,000 EURO every year. Given the high production volumes involved, yarn as a cost factor has always been of decisive importance in the circular knitting industry.
As a result, knitting faults due to yarn breakage have traditionally been just as counterproductive as, for example, the use of higher yarn qualities due solely to an attempt to reduce yarn breakage rather than to improve the targeted fabric quality. This situation offered major scope for rationalization and a real challenge to machine developers.
Relative movement technology - the breakthrough for reduced yarn stress.
The relative movement technology concept was born at the beginning of the eighties. The aim was to reduce the number of yarn deflection points and so minimize stress on the yarn based on the relative movement of the sinker to the needle. The German circular knitting machine manufacturer Mayer & Cie. recognized the immense possibilities inherent in this idea, purchased the licence rights and developed "Relanit" technology up to the series production stage. The first circular knitting machine featuring the new technology was presented at the ITMA Paris in 1987 as the Relanit 1 - a circular knitting machine with one needle type for single jersey and single jersey plated.
While conventional single jersey technology encompasses up to 8 deflection points for the yarn in the stitchforming zone, the Relanit technique cuts this by half, leaving only four deflection points. This exposes the yarn to substantially less stress.
With just under 5,000 machines supplied to the market up to the present, this machine type quickly progressed to become the number one selling circular knitting machine in the world today.
Reduced yarn costs through Relanit technology.
Use of Relanit technology permits a marked reduction of yarn costs. Firstly because it permits simpler yarn qualities to be processed without problems in all the Relanit machines. Here alone, the resulting yarn cost savings are considerable. Another benefit is the marked reduction of yarn waste. The Relanit technique results in tangibly fewer faults in the fabric. Less yarn breakage means fewer holes.
Due to the design, oil stains in the fabric are also largely prevented. Because a Relanit circular knitting machine is not fitted with a separate sinker and sinker cam ring, the oily lint which is an inevitable by-product of the knitting process falls to the outside, and is thus no longer able to come into contact with the fabric.
Relanit technology pays dividends.
The slightly higher initial investment in a Relanit circular knitting machine is quickly redeemed.
Tests performed under practical application conditions show that a conventional single jersey circular knitting machine causes on average 5 faults per hour, whereby it is possible to make the following rough assumption: 3 faults due to holes, i.e. yarn breakage, and 2 faults due to oil stains in the fabric.
Using relative movement technology - according to tests carried out using Relanit machines - production is possible with a maximum of 1 yarn breakage per hour and oil stains in the fabric are practically eliminated.
If we calculate 0.5 metres of wastage for each fault, the knitting factory which uses a Relanit machine will incur around 2.0 metres of wasted fabric less per hour. Taken over the year, this quickly adds up to thousands of EURO. Added to this is only around 20% of the downtimes experienced with conventional single jersey machines - meaning a further increase in productivity, and the capability to work at higher speeds due to the minimized yarn friction in the stitchforming zone.
In summary, after fifteen years of practical experience with Relanit technology, it is possible to conclude that this development represented a major step forward for the circular knitting industry in terms of both quality of the knitted fabric and also productivity.
Circular knitting machines using Relanit technology currently on offer.
Today, knitting factories enjoy a wide choice of single jersey machines using Relanit technology. Mayer & Cie. offers the Relanit 1.6 with 1.6 feeders per inch, as well as the fully electronic 1.6 E, each in a 30- and a 34- diameter. Both machine series use the full 3-way technique and are also available with striping unit as the Relanit 1.6 R and 1.6 ER. The combination of stripes with the relative movement technique offers the benefit that no structural parts block the view or access to the needle bed, so ensuring reliable and simple operation.
A high number of feeders per inch and consequently high production output are offered by the 2.4 E as a fully electronic version (72 feeders for a 30- diameter) and the mechanical Relanit 3.2 with 30" diameter and up to 45 rpm. The Relanit 3.2 is the ultimate highperformance versatile single jersey machine using Relanit technology - in a sense a "one-for-all" Relanit.
The Relanit 3.2 II was conceived specifically for the use of synthetic yarns. While it operates as standard with yarn feeders placed between the needle curve with cotton, it can be fitted with a yarn feeder before the needle curve in case of special requirements involving fashion synthetic yarns and elastomer.
As a jacquard machine with electronic pattern setting, the Relanit SE offers mini jacquard at the flick of a switch, and comes for example with 72 feeders in a 30" diameter.
The Relanit E has been the accepted single jersey standard for many years for the production of single jersey jacquard structured knits - with electronic individual needle selection. Today, the Relanit 2.4 E (30-/72 feeders) as follow-up model sets standards in terms of both quality and fashion, can be reset to new patterns in just seconds and knits without faults at high outputs.
The wide range of Relanit machine types available supplies a customtailored solution to almost every conceivable application arising in the modern knitting factory - at an initial outlay which offers excellent viability through a fast return on investment.
[ 01.01.2003 ]
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Fewer deflection points substantially reduce stress on the yarn.
Direct view of the yarn feeder hole in the Relanit. Obscured view of the yarn feeder hole, faults are only detected in the fabric.
An exemplary workplace also with stripes: No structural elements obscure the view or the access to the needle bed.
The Relanit 3.2 is highly productive in terms of quality and performance - in a certain sense the "one-for-all" Relanit.
Full electronics with electronic individual needle selection - the Relanit 1.6 E is the single jersey machine which stays ahead of fashion.
The further development of the world's first circular knitting machine to use relative movement technology and electronic individual needle selectio, the Relanit E, is the Relanit 2.4 E. Today, it sets the standard in terms of quality and fabric design.
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