Rotor Spinning Machine R 40- Trend-Setting Innovations

for Profitable Rotor Spinning

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As a result, the R 40 is characterized by:

• An optimal yarn quality with the most techno-logically advanced spinning box.

• The spinning box has an optimized geometryto the machine and an exceptionally goodspinning stability which enables the achieve-ment of highest production speeds.

• Rieter basic machine concept with the biggestcan and package dimensions offers an in-crease in productivity for a given floor space.

• The modern Rieter automation concept hasbeen improved to attain high piecing reliabil-ity and quality at the highest speed. The resultis maximum machine efficiency at very highproductivity.

• An innovative drive system has been imple-mented to minimize energy consumption.

Rotor Spinning Machine R 40- Basis for Profitable Rotor Spinning

Since ITMA Asia in 2001, the Rieter R 40 rotorspinning machine has set new benchmarks byan optimized combination of the most advancedspinning technology and a most modern ma-chine concept.

The official sales release of the R 40 was in2002. The R 40 impresses the customers by itshigh productivity and by its fast and reliable au-tomation. In this article, we can only point outsome of the benefits of this new machine. Fea-tures such as the ease of operation, user friend-liness and the simple approach to maintenancecan be mentioned, but they must be experiencedto create the full impression.

Optimal combination of leading tech-nology and modern machine concept

The R 40 is the combination of a new core, thespinning box SC-R, and as a basis, the reliableR 20. Its realization became possible after Rietertook over large sections of the Suessen Groupat the beginning of 2001. The target was to com-bine the most interesting features of the Suessenspinning box, a further development of the 2.5million spinning boxes delivered worldwide,and the most advanced automation concept ofthe R 20.

Fig. 1:Optimal combination of leading tech-nology and modern machine concept

Dr. Stephan Weidner-Bohnenberger,Head Product Management Rotor, Rieter Ingolstadt

Superior yarn quality with the mostadvanced spinning box technology

The new SC-R spinning box is based on thehigh quality of the previous generations andcompared to other spinning boxes available onthe market, and includes a number of innovativefeatures, of which the main ones are:

• The fixed fibre beard support guarantees con-stant conditions at the point in the spinningbox, where the opening roller combs out thesliver. In the SC-R box this point cannot be in-fluenced by any differences in the shape of thesliver, e.g. given by the pressure inside thespinning can.

• The adaptable BYpass allows the extraction oftrash and small fibre parts by the opening unitto be influenced. The adaptation of the airflowin the trash extraction chute of the SC-R spin-ning box results in better spinning condi-tions. High trash content in the sliver exertsless influence on the yarn quality.

• The unique possibility to adapt a specialopening unit offers further improvements inyarn quality and productivity compared to astandard spinning box. This unit is of specialinterest for customers, specialising in syn-thetic fibers.

The SC-R spinning box can be equipped with awide range of spinning elements, such as rotorsfrom 28 to 56 mm diameter, nozzles and open-ing rollers with different surface structures andcoatings. This range is subject to a steadygrowth due to constant research & developmentin our laboratories and by further developmentof materials and coatings. As a remarkable dif-ference to other suppliers, the SC-R box alsocan be equipped with special channel insertswith a SPEEDpass allowing the increase of theairflow particularly in the opening unit. Addi-tional airflow for example, helps to support thefibre transportation when producing coarse yarncounts at high production speeds.

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Fig. 2:Advantageous yarn quality with themost advanced spin box technology

Best spinning stability for highestproduction speed

Rotor spinning is a well established spinningprocess today. The high spinning speeds are intune with the stability of the spinning box. Ex-tensive investigations have shown, that the dis-tance between rotor groove and takeoff roller iscrucial for optimal spinning conditions.

The incorporation of the SC-R spinning box inthe R 40 machine provides an especially sharpangle between the axle of the nozzle and the di-rection of the yarn. This increases the false twisteffect before the TWISTstop element and thus in-creases the spinning stability. A higher spinningstability facilitates either the application of high-er rotor speeds or the reduction of the yarn twistand therefore the increase of the delivery speed.

With its excellent conditions for spinning sta-bility, the SC-R spinning box permits achieve-ment of the highest productivity per spinningposition. Customers familiar with several typesof Rieter rotor spinning machines report signif-icantly increased spinning speeds with the samesliver for the same knitting yarn compared to thelast version of the R 20. Cross-checks per-formed at customers, who have installed the lat-est technology of our competitor’s spinning boxshowed an 8 % higher production per positionwith the identical products. This advantage canbe used to increase the mill productivity as wellas to revise the raw material requirements in or-der to reduce its cost.

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Sketch Cross section

Sp9inning geometry

Sketch Cross section

Sp9inning geometry

Fig. 3:Best spinning stability for highest pro-duction speed

Productivity by a modern machineconcept

For a profitable operation, the combination ofthose very high productive spinning boxes in amachine has to be accompanied by intelligentmachine features. The machine drives of R 40allow rotor speeds of up to 150’000 rpm and apossible delivery speed of up to 255 m/min.This gives scope for high productive spinning ofhigh quality yarns, also covering increases byfuture developments of spinning elements.

A rotor spinning machine with a large numberof rotors and a high productivity, has to handlea large volume of material in a large number ofcans and has to handle many yarn packages.Faster production increases the frequency ofpackage changes. So the machine automationhas to be able to handle more spinning posi-tions, and more stops.

The modern concept of R 40 fulfils these re-quirements. It allows the biggest possible use oftransportation units: The wide gauge of the spin-

ning positions facilitates the placing of cans asbig as 18_” (470 mm) in diameter in a space-saving two rows arrangement under the ma-chine. Additionally a significantly narrowerplant layout is possible with R 40 . The combi-nation of extra-wide gauge and substantiallynarrower machine width makes the R 40 themost productive machine per given floor area.

The R 40 winding units can produce very largepackages with a diameter of 340 mm. This al-lows - by far – the heaviest packages on themarket. Compared to other machines, the num-ber of cans and packages to be changed andmoved is reduced by up to 20%! This saveslabour, reduces the number of empty tubes incirculation and reduces interruptions of thespinning process, which influence the machineefficiency. The wax blocks in the yarn waxing de-vice are about 4 times bigger then in competi-tors machines. This also reduces the frequencyand cost of changing the waxing blocks.

Four robots option to increase efficiency with coarse yarn counts

R 40 can be equipped with four robots, effec-tively doubling the capacity of the machine au-tomation. So the R 40 is able to handle a largeworkload on a long machine with a fast packagebuild up at coarse yarn counts, high deliveryspeeds, possibly small package sizes and pos-sibly with a high rate ends-down . With four ro-bots even a coarse yarn Ne 7 (Nm 12) can beproduced with a long R 40 machine of 320 ro-tors at a machine efficiency of 96 %! Further-more the start-up time of a machine after astandstill period is reduced by half with four ro-bots, increasing the overall efficiency of theplant. This option is backed up with concepts offlexible and easily adaptable working procedure.An intelligent service concept guarantees thatthe other robots serve all rotor positions of themachine, while one of them is in a service posi-tion.

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Fig. 4: Lowest floor space requirement com-bined with largest cans

R 40 supports the operator intervention by a se-lective guidance. This includes programmablesignal lights on the machine gearing end and tailend, signals on the robots, sections and spinningboxes. It is completed by big plain text displayswith graphical support on the robots and on thetouch screen display of the machine control unit.This concept positively influences the machineefficiency while optimizing the required workforce.

Highest speed and efficiency with state-of-the-art robotic automation

The robot of the R 40 itself has remarkable fea-tures making it outstanding in performance andspeed. Its advantages are based on the modularAERObotic concept: The robot is equipped withindependently acting electro-pneumatic units.Each unit is performing a specialised task. Thissignificantly speeds up and eases the setting ofthe robot and indicates any service needs. Oper-ation and maintenance are assisted by clear in-formation with graphics in a big plain text display.

The robot’s microprocessor controls all the ac-tions. It constantly communicates with the ma-chine control. Therefore, the travelling robot canquickly and directly approach the next workingposition, centring at the box with a laser beam. Acleaning module cleans the box, rotor and the ro-tor groove with a concentrated jet of compressedair, on demand assisted by mechanical cleaning.The robot performs all necessary tasks for piec-ing. It prepares the end of the sliver and the endof the yarn. For starting winding on empty tubes,the robot carries a seed yarn which is afterwardssucked into the filter chamber.

The complete cycle time of a combined piecingand doffing operation on the R 40 robot is under25 seconds. Combined with a very high piecingefficiency, the robot is able to keep up the ma-chine efficiency to the utmost. The starting timeof the R 40 after a machine stop is kept to a min-imum.

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Fig. 5:Four robots option to increase effi-ciency with coarse yarn counts

Quality of piecing at an utmost level with the unique piecing principle

The piecing principle of the Rieter SYNCROtopsystem is based on the fact that the Robot hasfull control of all the speeds. The piecingprocess is performed at a defined and constantrotor speed, which can be set as needed (i.e.usually between 65% and 100% of the normalrotor speed). This allows constant and definedconditions for all other corresponding speeds,such as sliver feed and yarn takeoff, indepen-dently from the actual time consumption of theindividual steps during the piecing process. Al-though each step can be optimized to the needsof the specific product, the piecing is performedunder equal conditions, permitting the highestpossible rotor speeds. All piecings go throughthe yarn clearer at the spinning position. Thepiecing is checked for its thickness using a spe-cial channel of clearer settings.

This results in very uniform piecings and be-cause the piecing was done at a high rotorspeed, it has a high resistance.

Fast and easy lot change with VARIOdraft

The R 40 is equipped with an intelligent combi-nation of frequency converter driven motors.This enables the fastest possible lot changes.Draft, winding tension and twist can be individ-ually set on the touch screen of the machine dis-play, without gear changes. This is known asVARIOdraft and is already used on the R 20. Ad-ditionally the R 40 is equipped with an inverterdrive for rotor speed. The setting of all speedscan be carried out independently in small incre-ments during machine operation without stop-ping of the machine.

This is a big advantage for fast lot changes: Af-ter changing the spinning elements the speedsneed only be set at the machine panel. Usuallya few packages are tested in the laboratory aftercheck of the yarn count. The fine-tuning of draftis then done on the touch-screen. The full pro-duction can be started right away without stop-ping the machine and without a time-consum-ing search for the correct gears in the tool shop.The combination of these features on the R 40results in a machine efficiency increase of 1%or more. Each 1% increase in machine efficien-cy results in additional yarn production withoutany production cost! With an Ne 7 (Nm 12) thismay signify more than 23’000 kg of additionalyarn per machine per year.

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Fig. 6:Quality of piecing at an utmost levelwith the unique piecing principle

100%

80%

Rotor speedStart of piecing

Time of piecing cycle

Low production cost with efficient energy saving

An important target when designing the new R 40was the minimized energy consumption. The Ri-eter machine concept of low energy consump-tion had to be improved further. The focus wasset on the two main areas of consumption: therotor drive and the main suction systems.

The rotor drive system is by far the biggest en-ergy consumer in a rotor-spinning machine. Itsenergy consumption depends on the pressure ofthe tangential belt to the rotor shafts, which isneeded to ensure rotor speed increase. With theR 40, this pressure was generally reduced, be-cause the robot is able to increase the belt pres-sure at an individual spinning box for fast speed-ing up the rotor. Therefore, allowing the powerconsumption for the rotor drive to be reduced.

The second biggest consumption source is themain fan. It has been redesigned for the R 40.The new fan has a bigger volume. Thanks to itshigh efficiency it allows a lower power installa-tion than for other machines. A new intelligent

concept is used to keep constant spinning con-ditions with minimum energy consumption,even if the filter mat becomes loaded. An elec-tronic sensor for the negative pressure starts au-tomatic cycles to remove the filter mat as soonas a certain decrease of negative pressure oc-curs. Only if the decrease cannot be neutralizedsufficiently, the manual removal of the filter matis requested by a signal to the operator. Com-pared to conventional systems, the interval ofoperator interventions is reduced by up to threetimes. Alternatively, the removal of the filter matis possible by a fully automatic vacuum waste re-moval system. Admitting small deviations in thenegative pressure which do not influence spin-ning, with the R 40 system there is no need toimplement additional power consumption toovercome the resistance of the growing filtermat.

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A new rotor spinning mill with 10 R 40: a showcase for high productivity

Best mill experience by customers

In the short period since its market introductionthere there have been sold over 190 machinesof the R 40. The main customers of R 40 are inEurope and Asia. Shortly after installation thecustomers became acquainted with the advan-tages and stated:

• R 40 offers excellent yarn quality with the SC-R spinning box with, significantly increasedproduction speeds. The possibilities to han-dle sliver with high trash contents was great-ly improved with the advantage of the BYpasssettings.

• The spinning geometry with the SC-R box of-fers a better spinning stability, facilitatinghigher yarn strength or alternatively allowingimplementation of lower yarn twist.

• Big can and package dimensions, which areonly possible on the R 40, are crucial for thereduction of the working load for materialflow. This fact gains even more importancethan before with such long and productivemachines.

• Fast lot changes and a fast start-up of the R 40after a machine stop are possible with theVARIOdraft inverter drive system.

• The very fast robot of the R 40 and its high ef-ficiency for piecing allows a long machine toreach full working efficiency within only about75 minutes. With four robots per machine,this time is nearly halved. This speed is real-ly adding flexibility to a spinning mill.

• The measures to minimize power consump-tion in the R 40 are effective, as could beproven by a direct comparison under equalrunning conditions.

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Rieter Machine Works Ltd.Klosterstrasse 20CH-8406 WinterthurT +41 (0)52 208 71 71F +41 (0)52 208 83 20

Rieter IngolstadtSpinnereimaschinenbau AGFriedrich-Ebert-Strasse 84DE-85055 IngolstadtT +49 (0)841 9536 01F +49 (0)841 9536 850

Rieter CZ a.s.Csl. armady 1181CZ-56215 Ústí nad OrlicíT +420 465 557 232F +420 465 524 237

http: //www.rieter.comE-mail: sales.sys@rieter.com

The data and illustrations in thisbrochure refer to the date of printing.Rieter reserves the right to make any necessary changes at any timeand without special notice. Rietersystems and Rieter innovations areprotected by patents in most indus-trialized countries.

1747e–AEAE–6–Printed in Switzerland