Automation in Ring Spinning Machines


Innovations are carried out by Spinning Machine Manufacturers across the globe.

This presentation is intended to focus and sharing of information in perspective of Toyota Industries corporation and KTTM.



Need for Automation

· Man Power & Increasing Man Power Cost.

➢ Spinning Mills are located in remote areas.

➢ Difficult to get manpower.

➢ Job other than actual production should be transferred to machine.

➢ Example – Auto Doffer on Ring Frames.

· Changing job preferences.

➢ Qualified Textile Technologists prefer to take white collar job like

Marketing, Fashion Designing, Garmenting etc.

➢ Not keen to work in production.

➢ It should be possible to run production plant with few supervisory staff.

➢ Example – Ring Data System, on line machine monitoring system, on line quality monitoring .

Material Transportation

➢ Material Transportation, within a spinning plant is a necessity.

➢ It does not add any value.

➢ Hence Link Winder System, Automatic Roving Transfer Systems.

· Increasing fashion consciousness resulting in smaller lot size.

➢ This results in frequent changes in machine settings.

➢ Therefore, Servo Drive system, which allow machine setting by

touch of button.

· Ease of Machinery Maintenance.

➢ Machines equipped with self guided informator, automatic

lubrication, automatic waste removal.

Automation on Ring Frame

1. Ring Rail Movement Conventional CAM Lift System


  • · Till recently most manufacturers use this mechanism.
  • · Cost effective & proven design.
  • · Involves too many components and mechanisms.
  • · Setting depends on human skills and require more time
  • · More space required
  • · More inventory needed of all parts
  • · Wear and tear of parts
  • · Fine adjustment difficult

1. Ring Rail Movement – Alternative System

a) Servo Drive with Screw Lifting System


  • · Very reliable system.
  • · Controlled by servomotor and servo drive.
  • · Setting alteration by key pad data entry.
  • · No special skill needed for setting
  • · This system is still little expensive to implement
  • · Paticularly in Indian context.
  • · Assy time reduces enhancing manufacturing capacities.

1. Ring Rail Movement – Alternative System

b) Electro Lift System – Innovative idea


· Setting done at the press of a button.

· No special skill needed for setting

· Combines the advantages of the servo drive system and at the same time is cost effective.

1. Ring Rail Movement – Alternative System

This system was possible to implement because of –

Thanks to companies like Siemens, Danfoss, A66, Mitsubishi etc.. for bringing in advancement in motion & control electronics.

2. Drive to Drafting Rollers – Conventional System


  • · Conventional System, all gear drive
  • · Many gears to be changed for changing the count / twist. Time consuming process.
  • · Multiple types of yarns can be produced but needs additional mechanisms attached.
  • · Increased need for regular maintenance & repairs.
  • · Inventory of parts.

2. Drive to Drafting Rollers – Alternative System

Electro draft System


2. Drive to Drafting Rollers – Alternative System

Electro draft System

  1. · All rollers driven by individual motors, controlled by individual drives.
  2. · Possible to alter draft and twist from the key pad. Fine tuning of twist & draft adjustments possible.
  3. · Possible to manufacture fashion yarn like multi twist , multi count , slub yarn.
  4. · Interfacing & drive communication through Profibus and other types of protocols makes controls simple and very accurate.

3. Pneumafil – Suction Pressure Monitoring System

Present System :

– Pneuma motor works at fixed rpm.

– Suction values achieved is fixed and has no relation to the material or count being processed.


Alternate System

  • · Pneumafil motor is controlled by inverter.
  • · Suction pressure can be set in inverter. This is constantly monitored by pressure transducer.
  • · Suction pressure can be set in relation to spindleage of the machine, count, and raw material being processed.
  • · Reduces power consumption

4. Automatic Doffer


  • · Automatic Doffer system is now gaining customer acceptance.
  • · Reduced manpower requirement.
  • · Increase machine productivity.
  • · Reduce need for supervision.
  • · Increase life of components and accessories like spindle & bobbins.

Link Coner System


  • · Automatic Cop Transfer from Ring Frame to Winder.
  • · Possible to implement spin identification system. ( on line quality monitoring & identifying the spindle producing inferior quality yarn).
  • · No mix up of different counts.
  • · No deterioration of yarn quality due to manual handling.

Automatic Roving Transfer

  • · Automatic Transfer of Roving Bobbins from Roving Frame to Ring Frame.
  • · No deterioration in Roving quality due to storage and handling.
  • · Better yarn quality.


Automatic Data Acquisition :


  • · All machines are connected to a Central Computer.
  • · Two way communication between the Computer and Machine can be established.
  • · Possible to change the speed parameters from the Computer.
  • · On line monitoring of the machine status.
  • · Data acquired can be converted to production report. No need to manually record the production information from the machine.

8. Automatic Breakage Control


  • · Machine can be interfaced with the Ring Data System.
  • · Spindle speed can be automatically increased / reduced depending on the yarn breakage level

Machine Brake


  • · Brake is required on Ring Frame to prevent snarl formation while stopping the machine.
  • · Conventional system uses electro magnetic or mechanical brakes.
  • · Alternate system
  • · DC Injection brake from main inverter.
  • · Optimum braking time by varying the parameters.
  • · Elimination of all mechanical parts which require frequent resetting.

Computerized Production and Quality monitor­ing system for Spinning Mill


To be successful in today’s demanding yarn market, modern spinning mills need to be fully focused on performance and quality. Only spinning mills having real time production and quality data for the entire production process can achieve an optimum relationship between quality and efficiency.

With the SpinMaSter system, BarcoVision offers a solution for production and quality monitor­ing covering the complete spinning mill.

Through a graphical user interface, SpinMaSter users are constantly informed about the actual situation in the spinning mill. Powerful analysis tools allow instant identification of poor performing machines and spindles, resulting in a faster reaction to problems and an increased efficiency and quality level.

Spinning preparation




Machine monitoring

Cards, draw frames, lappers, combers and flyers are connected to the system by means of a Data Unit. This Data Unit detects the production speed and run time. This information, in combination with the number of deliveries and the sliver count, allows a calculation of the production per hour and per shift.

The various stop motions on the machines can also be connected to the Data Unit for transmitting automatic stop causes to the central system.

By using the keyboard of the Data Unit, associates can make manual declarations to specify more detailed stop reasons or log other events to the monitoring system.

Quality monitoring: KITMaster

In connection with Trützschler cards and draw frames, BarcoVision offers the KitMaSter Sliver Information System.

In addition to production information, KitMaSter also provides on-line information on sliver count, sliver evenness, spectrogram and length variation curves. This results in 100% real time quality assurance.

Installing KitMaSter in spinning preparation eliminates costly and time consuming sampling and lab tests and offers numerous advantages, such as improved quality, no loss in raw materials required for sampling, and cost reduction in personnel and lab equipment.


BarcoVision’s SliverWatch system, mounted on the first step draw frames for foreign fiber detection, can also be connected to the central system. As such, statistics on the number of draw frame stops for foreign fiber are available per individual sliver can.

Production data such as machine efficiency, produced sliver length, number of can changes, number of production stops as well as quality stops are available in real-time and on a shift or lot base.

Ring spinning Machine monitoring

Ring spinning frames are connected to the SpinMaSter system by means of Data Units for machine based monitoring.

The Data Unit automatically detects delivery speed and automatic stops such as doffing and hand stops. Through the keyboard, the operator can enter additional down time, message and administrative declarations.

On the color-coded layout of the mill, the frames are pictured in certain colors, each color indicating a certain machine status or alarm condition. The user selects the type of information to be displayed: production data, speeds, stop rates, efficiencies, …

User definable “filter sets” allow the user to display only these machines which correspond with a certain condition, for example all machines with an efficiency less than 90%, all machines waiting for an interven­tion, …

Spindle per spindle monitoring

More and more spinning operations want to monitor the individual ring spindle for yarn breaks and spindle speed. OptiSpin, offering an individual detector for each spindle which detects run/stop and speed, monitors the ends down level and reports slipping spindles.

Connected to SpinMaSter, much additional information is available in the data base to give technicians a detailed ends down analysis and a tool for improving frame efficiency.

A mouse click on a particular ring frame allows the user to select any detailed report, such as the spindles with highest breakage level, slipping spindles per machine, yarn breaks in function of the bobbin build up, during up and down movement of the ring rail, …

Ends down levels, slipping spindles, frame and spindle efficiencies are reported by doff, as well as by shift, day, week and month. Trend reports highlight recurring problem spindles.

Stops are always assigned to the right spindle, regard­less the length of the machine. Interfaces are available to the speed inverter of the ring frame, to increase the speed in case the ends down level remains below a defined threshold. This way, an optimum and consis­tent quality level is achieved at maximum efficiency.





Spindle per spindle monitoring

On winders, machine monitoring provides little practi­cal data. Monitoring the individual behavior of each spindle or drum on the winder provides information that can be used to improve production and quality.

For each position, the following data elements are required:

· Run time and stop time.

· Number of stops.

· Number of doffings.

· Number of yarn breakages.

· Yarn clearer cuts and red lights.

· Stop time for red lights.

· Time for doffing.

SpinMaSter collects this information from each position on the winder by means of a special interface board installed for each spindle or by an interface to the machine information system already available on the winder. In the latter case, only the information transmitted by the machine unit is available for reporting.

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Autocoro S 360–Tech Data–Special Features–Rotor Spinning






Quality guarantor 1: Digital precision control

The precondition for perfect piecings that are reproducible at any time is highest precision: for fibre feed and return into the rotor, and for yarn take-up from the rotor. With DigiPiecing, 100% digitally controlled single motors guarantee this: The Single Drive Sliver Intake (SDSI) sets the course for the fibres to be perfectly fed into the rotor and the Single Drive Take

Up (SDTU) controls precisely dosed yarn feeding and exact take-off.

The complete piecing process goes without manual mechanical settings and thus eliminates the inaccuracies involved. All settings are defined via the Informator’s touch screen.

Reliable and safe Autocoro packages

The “inner structure” of your packages ensures trouble-free and productive running in downstream processing. The Oerlikon Schlafhorst research and development team continuously works on new solutions for packages that run

even more quickly and safely. Therefore, Autocoro packages feature an optimum unwinding behaviour, an excellent edge structure and a uniform density. The pneumatically controlled package lift-off device protects the package surface during production interruptions and package doffing.

Packages always in the right format,

any one identical to the others

Due to manifold possible settings at the Autocoro S 360, you can always supply your customer with exactly the package he requires: up to 5 kg in weight – and this with exact diameters and yarn lengths.

Quality guarantor 2: Consistent quality control In the Autocoro S 360, the most successful and most

sophisticated Corolab XQ clearer technology in the world not only ensures unequalled yarn quality, but also 100% digitally controlled piecings. Sensors at each spinning position guarantee that only perfect piecings and perfect yarn is wound on the package.

Every spinning position transmits a quality report where data about thick and thin places of every yarn lot and package are stored. All Corolab parameters are set centrally.


More kilograms, more sales

The Autocoro S 360 is designed for highest

efficiency. You will bring out the best in your

installation with intelligent features


Higher production – day after day

360 spinning positions, a take-up speed up to 230 m/min and the Corobox SE 12 for rotor speeds up to 130,000 rpm: The Autocoro S 360 features continuous top performances. For more kilograms of yarn.

DigiPiecing ensures highest efficiency

Thanks to the new DigiPiecing, the success rate in piecing increases. And thus productivity in normal production increases, too. Lot changes, too, are considerably quicker.

Be quicker: central settings and simple handling This is how comfortable the Autocoro S 360 is: Thanks to the Intelligent Drive System (IDS), all settings for production are entered centrally on the Informator.

These settings comprise e.g. the infinitely variable speed adjustment of all components involved in the spinning process, as e.g. opening rollers or rotors. Also draft and yarn twist can be adjusted – and everything during normal spinning operation.

There are only plug-in or magnetic connections in the spinbox – all spinning components are directly accessible and can be replaced simply and without tools. Nor must the complete installation be shut down for replacement.

More spinning stability, less costs: with EVA In addition, the Autocoro S 360 features the proven

Electronic Vacuum Adjustment EVA by Oerlikon Schlafhorst. EVA guarantees a constant vacuum at every spinbox – independent of the filling level of the collecting chambers for dirt, fibres and yarn, and independent of the machine length

With EVA it is possible to precisely control the spinning vacuum at your Autocoro S 360. The vacuum setting – optimised by EVA – reduces the number of yarn breaks and thus increases the productivity of your installation. At the same time, the optimised spinning vacuum means less energy demand.

Technical Data

Autocoro S 360

Machine type

Oerlikon Schlafhorst rotor spinning machine Autocoro S 360 with 24–360 spinning positions – Semi-automatic piecing technology DigiPiecing – Sectional structure with 24 spinning units per


– Spindle gauge 230 mm

Technological Data

Raw materials

Natural and manmade fibres and their blends Fibre length up to 60 mm

Yarn count range

145–14.7 tex/Nm 7–68/Ne 4–40

Sliver feed

7.0–2.5 ktex/Nm 0.14–Nm 0.40/ Ne 0.08–Ne 0.24

Draft 20–450fold (IDS)

Basic machine

– IDS Intelligent Drive System. Piecing parameters, rotor speed, take-up tension, spinning vacuum, opening roller speed, yarn twist and draft are infinitely variable

– Multi-colour LED at every spinning position for operator guidance

– Conveyor belt per machine side, for package removal

– Optimised removal of fibres/waste on the trash removal conveyor belt *

– Central lubrication and bearing temperature monitoring

Spinbox Corobox SE 12

– SDSI Single Drive Sliver Intake, single-motor driven sliver intake

Intake speed 0.1–8 m/min

Draft range 20–450fold (IDS)

– Axial rotor bearings with MRPS Magnetic Rotor

Positioning System or hybrid bearing assembly – Radial rotor bearings with Twin-Disc for rotor

speeds of 40,000–130,000 rpm (IDS)

– All Belcoro spinning components can be replaced simply and without tools

Winding head

Package formats

– Cyl. packages up to 320 mm

– Tap. packages 1 °50‘ up to 280 mm *

Tube dimensions cylindrical smooth / flanged

–- Ø 54 x 170 mm/Ø 54/42 x 170 mm

Tube dimensions tapered

smooth / flanged

– 1 °50‘ Ø 65/54 x 170 mm/Ø 65/43 x 170 mm

Angle of wind

28°, 30°, 33°, 35°, 39°, 40°

Take-up speeds

Depending on the machine length at 30° angle of wind:

–- Standard equipment with roller guide for the yarn guide rods.

– Cylindrical 230 m/min

– Tapered 200 m/min

Yarn guide traverse

–- Cylindrical 147–155 mm

– Tapered 147–150 mm

– The traverse displacement is infinitely variable from 0–4 mm

– Anti-patterning through periodical change of yarn guide motion

Waxing device *

– The wax roll is single-motor driven

– A collector prevents any accumulation of wax particles in the Corobox area

Pneumatic package lift-off device *

– Electronically controlled pneumatic package lift­off device

– Gentle lifting of package when package is full or a yarn break occurs

Stop upon reaching the yarn length or the package diameter

– Length measuring unit for the production of

packages with defined yarn lengths or

– Electronic stop by means of Hall sensor upon

reaching the preset package diameter


– Digital control with EIS Event Identification

System for 100 % digitally controlled piecing

– Digitally controlled sliver intake SDSI Single Drive

Sliver Intake

– Digitally controlled yarn feed and yarn take-up SDTU Single Drive Take Up

– Digitally controlled pneumatic yarn storage – Digital optical piecing check

Suction system

– EVA Electronic Vacuum Adjustment for

electronically controlled constant spinning


– Spinning vacuum 60–95 mbar (IDS)

– Yarn residues, waste and fibres are collected separately in a three-chamber system

– Possible connection of collecting chambers

for waste and fibres to central waste disposal systems *

– Spark detector


– Input of spinning and piecing parameters with touch-screen operator panel

–- Evaluation of data by Informator

– Representation of data on screen or via a printer

Corolab XQ Digital Technology *

– Digital sensors Corolab XQ for the registration of yarn diameter deviations at every spinning position

Travelling cleaner *

– Sohler-Neuenhauser travelling cleaner for blowing/cleaning the spinning units and suction of fibre fly

Spinning cans

Spinning can dimensions round cans: Diameter

457 mm (17.5“) (two rows)

530 mm (20“) (three rows)

Height 900 mm to 1,200 mm

(36“ bis 48“)

Spinning can dimensions rectangular cans:

220 mm width x 970 mm depth x 900–1,200 mm height (1,070 mm when using can supports)

* Option



Autocoro S 360-The first rotor spinning machine with High Productivity



The new Autocoro S 360: The first rotor spinning machine with DigiPiecing offers you outstanding productivity levels: with 360 spinning positions,

take-up speeds up to 230 m/min and rotor speeds up to 130,000 rpm.

Autocoro package quality and Belcoro yarn quality

With Twin Disc bearing and Magnetic Rotor Positioning System (MRPS), the Corobox SE 12 guarantees highest productivity and Belcoro yarn quality for all yarn counts, raw materials, blends and applications.

Make use of the brandname for the most sought-after rotor yarns world-wide: Belcoro. The Auto­coro S 360 offers you best prerequisites for Belcoro certification.

Technical data

Rotor speeds

40,000 to 130,000 rpm

Take-up speeds Up to 230 m/min

Piecing DigiPiecing

Yam quality monitoring Digital Technology Corolab XQ


Autocoro packages up to 320 mm and 5 kg weight

Yam count range

145 to 14,7 tex/Nm 7 to 68/Ne 4 to 40

Digital Technology – the quality guarantor Your are doubly secure with the innovative DigiPiecing. The state-of-the-art SDTU Single Drive Take Up and SOS! Single Drive Sliver Intake digital technologies from Oerlikon Schlaf­horst guarantee piecings that are indistinguishable from the parent yarn: 100 % digitally controlled, 100 % digitally checked. The result is: Highest piecing precision, infinitely reproducible on every single spinning position.

The market-leading Corolab XQ digital yarn monitoring system in the Autocoro S 360 guaran­tees consistently checked yarns.

The intelligent operating concept saves position patrols and thus personnel: Every spinning unit shows its production status by a coloured LED signal, visible even from a distance. All machine settings are entered centrally, safely, and simply on the Informator touch screen.

With EVA (Electronic Vacuum Adjustment), the Autocoro S 360 additionally ensures a constant spinning vacuum, considerably reducing the num­ber of yarn breaks and the energy requirements.





Autocoro 480–Rotor spinning machine-Special Features


The cleanest Belcoro yarn ever: Corolab XF with foreign fibre detection

To enable you to set standards in a global market that is increasingly

quality-conscious, the new Corolab XF combines classical yarn clearing with 100% foreign material detection. For even higher quality standards teamed with outstanding productivity.

Your know-how network worldwide

Oerlikon Schlafhorst is there for you at any time and in any place around the world. With technological innovations that get you to the top. With individual service and competent advice. And with highly qualified specialists who carry out trials just for you and adapt your machines optimally to your requirements.



The Corobox SE 12: 250,000 units worldwide testify to its all-round ability

The Corobox SE 12 speaks for itself. As the market‘s leading high-tech box, it meets every conceivable requirement in respect of quality, flexibility and productivity. The reliable all-rounder – engineered and made in Germany – excels with several technological highlights:

The Twin Disc bearing of the Corobox SE 12 permits permanent high speeds of 150,000 rpm at 480 spinning positions. Coarse yarns are spun at take-up speeds of up to 300 m/min – giving you maximum output every day.

All options

– Flexibility and top yarn quality for all yarn counts, raw materials, blends and applications

All weaving and knitting yarns

– For home textiles, such as curtains,

tablecloths, bed linen, towels etc. – For garment fabrics from tip to

toe: business, casual, outdoor,

sportswear, knitted garments

All yarns from coarse to fine from one sliver

– Draft range from 20 to 450fold – Yarn counts from Ne 4 to Ne 60 – Ideal for processing coarse slivers

up to 7 ktex too

Efficient fancy yarn production

– High-class fancy yarns adjusted quickly and precisely thanks to Fancynation and reproducible at any time on all machines

– Same take-up speed for smooth yarns and fancy yarns

– Higher productivity than any other fancy yarn system

Enhance your quality, produce profitably

Ratchet up your quality standards even more – with Autocoro 480, you always produce economically, even with an increasing number of clearer cuts. Three or four Coromat units offer sufficient capacity to execute a high number of piecing processes quickly and reliably.


Autocoro packages – prized by every downstream processing plant

The “internal architecture” of your packages is a very important efficiency factor in downstream processing. A perfect package structure guarantees trouble-free, productive processes there.

This is why the Oerlikon Schlafhorst research and development team works continuously on new solutions for packages that run even faster and more reliably. And this is why Autocoro packages exhibit optimum unwinding characteristics, an excellent flank structure and uniform density.

Always a made-to-measure package format

With the versatile setting options available on the Autocoro 480, you supply your customer with exactly the package he needs: up to 5 kg in weight and in all established package formats.

Nothing remains in the yarn that shouldn’t be there: the new Corolab XF with foreign fibre detection

For the Autocoro 480, we have considerably improved the established standard for digital yarn clearing. The innovative two-in-one system Corolab XF detects and records not only every single thick place or thin place but also foreign material in the yarn – with the utmost precision. The tiniest detail will not escape your Corolab XF – not even “stowaways”.

Simply enter the desired parameters centrally on the Informator: e.g. the fault length in mm or the fault thickness in percent.

Invisible, digitally controlled piecings

Digitally controlled and precisely positioned, every Coromat produces 100% identical piecings. The consistent sensor control provided by market-leading Corolab technology guarantees piecings that are indistinguishable from the parent yarn in the finished textiles.

The quickest fancy yarn system

Fancynation and the Autocoro 480 are made for each other. So you don’t need any technological or service partner apart from us to realise your fancy yarn production. And with

Fancynation, you produce high-grade fancy yarns at take-up speeds of up to 300 m/min – and thus more efficiently than with any other system.



Really simple, operator-friendly, profitable

The user-friendly fancy yarn software FancyPilot forms the basis of Fancynation. With FancyPilot, you create and

simulate effects in the minimum of time. And you benefit from quicker set-up times during the production and reproduction of your fancy yarns – with maximum production reliability and flexibility too.

Spinning with confidence: see in advance what your fancy yarn will look like

clip_image014See what will be possible with your fancy yarn even before production starts – in 3D simulations of woven and knitted fabrics. The production of your fancy yarns is

also undertaken with maximum assurance: digital Corolab technology monitors your fancy yarns reliably at every spinning position for the best possible quality. This gives you 100 percent control over the quality of your fancy yarn.

Effects in existing yarns can also be reproduced quickly and simply. Taking the pattern as a basis, Fancynation analyses the effect style and generates a data record for the Autocoro 480 from this.

Your own fancy yarn library

Fancynation acts as the “memory” of your fancy yarn production at the same time. You can access all spinning and piecing settings for fancy yarns already produced on your machines in a database. This enables you to reproduce any yarn quickly at any time and thus to react speedily and profitably to your customers’ wishes.

High production levels with three or four

Coromat units

Small lots, yarns with low twist, coarse yarns, small packages, fancy yarns: with the Autocoro 480, you are assured of decisive performance advantages. With three or four Coromat units, superior machine efficiency is obtained. Even quite small lots can be produced more economically.


Always choose the shortest route with EIS Only when the Coromat is positioned accurately to the

millimetre at the spinning position, it can produce optimum piecings and execute package doffing cleanly. On the Autocoro 480, this is ensured by top-quality high-tech components which will work precisely for many years.

Moreover, the Oerlikon Schlafhorst engineers have developed an intelligent control system for the Coromat. EIS, the Event Identification System on the Autocoro 480, guides every Coromat to the spinning position closest to it. EIS also detects where piecing is not possible – e.g. due to a missing sliver – and instead guides the Coromat to a spinning position where it can do something useful. Thus the piecing potential of all available Coromat units is always used to best effect.

Spinning instead of waiting thanks to flowing

package doffing

In order to further optimise package doffing, EIS offers the possibility of “flowing” package doffing, meaning that full packages can continue to be wound within a preset tolerance range if the Coromat is not close by at the time. On the other hand, packages which are already wound up to 95 percent

of the desired yarn length, for example, can also be doffed if the Coromat happens to be passing the spinning position.

The tolerance values for flowing package doffing can be freely defined.

The result is that spinning positions only have to wait for

the Coromat for the minimum of time and the capacity of the Coromat units is optimally utilised, thus increasing

the productivity of the machine.


Optimising quality simply “on the fly”

The Autocoro 480 makes quality controllable. All production settings are entered centrally at the Informator. The Intelligent Drive System (IDS) permits electronic quality optimisation via frequency inverters.

These settings include e.g. the infinitely variable speed adjustment of all components involved in the spinning process, such as opening rollers or rotors. Even the draft and yarn twist can be adjusted – and all this can be done during normal spinning operation.

Greater spinning stability, lower costs with EVA EVA stands for “Electronic Vacuum Adjustment”. Suction systems equipped with EVA guarantee a constant vacuum at every spinbox – independent of the filling level of the collecting chambers for dirt, fibres and yarn and regardless of the machine length.

With EVA, you can adjust the spinning vacuum at your Autocoro 480 precisely, from 60 to 95 mbar. For you this offers the advantage of high spinning stability, fewer yarn breaks and maximum machine productivity.

At the same time, the optimised spinning vacuum means a lower energy demand.


e-save by Oerlikon Schlafhorst: considerably lower energy costs

Developing more energy-efficient technologies is a top priority for our engineers. After all, Autocoro spinning mills invest about five percent of their annual turnover in energy – and energy costs are rising continuously.

On the Autocoro 480, several factors contribute to such marked reductions in consumption. The spinning vacuum, electronically optimised by EVA, not only maximises productivity but also has a positive effect on power consumption, for 20 percent of the energy requirement of an Autocoro spinning mill is devoted solely to producing the spinning vacuum.

More efficient through innovative, detailed solutions Further improvements that cut the power consumption include an intelligent system layout and the improved Coromat technology.




Technical Data Autocoro 480–Rotor Spinning machine


Oerlikon Schlafhorst rotor spinning machine Autocoro 480 with 48 to 480 spinning positions – Automatic piecing with digital technology

– Automatic doffing of full packages – Automatic box cleaning

– Sectional structure with 24 spinning positions per section

– Spindle gauge 230 mm

Technological data

Raw materials

Natural and manmade fibres and their blends Fibre length up to 60 mm

Yarn count range

145 to 10 tex/Nm 7 to 100/Ne 4 to 60

Sliver feed

7.0 to 2.5 ktex/Nm 0.14 to Nm 0.40/ Ne 0.08 to Ne 0.24


20 to 450 fold (IDS)

Basic machine

– IDS Intelligent Drive System

Rotor speed, take-up tension, spinning vacuum, opening roller speed, yarn twist and draft are infinitely variable

– Conveyor belt per machine side, for package removal

– Optimised removal of fibres/waste on the trash removal conveyor belt. *

– Central lubrication and bearing temperature monitoring

Spinbox Corobox SE 12

– SDSI Single Drive Sliver Intake, single-motor­driven sliver intake

Intake speed 0.1 to 8 m/min

Draft range 20 to 450 fold (IDS)

– Axial rotor bearings with MRPS Magnetic Rotor

Positioning System or hybrid bearing assembly – Radial rotor bearings with Twin-Disc for rotor

speeds of 40,000 to 150,000 rpm (IDS)

– All Belcoro spinning components can be replaced

simply and without tools

Winding head

Package formats

– Cyl. packages up to 300 mm

– HWP Heavy Weight Package for cylindrical
packages up to 320 mm and 5.0 kg *

– Tapered packages up to 4°20’ up to 270 mm *

Tube dimensions cylindrical


– Ø 54 x 170 mm / Ø 54/42 x 170 mm

Tube dimensions tapered


– 4°20‘ Ø 59/33 x 170 mm/Ø 59/28 x 170 mm – 3°50‘ Ø 63/40 x 170 mm/Ø 63/28 x 170 mm –- 3°30‘ Ø 62/41 x 170 mm/Ø 62/30 x 170 mm – 1 °50‘ Ø 65/54 x 170 mm/Ø 65/43 x 170 mm

Angle of wind

28°, 30°, 33°, 35°, 39°, 40°, 42°

Take-up speeds

Depending on the machine length

with 30° angle of wind:

–- Standard equipment up to 408 spinning units with roller guiding of yarn guide rods

– Cylindrical 180 to 220 m/min

– Tapered 135 to 200 m/min

– High take-up speed *

Standard equipment from 432 spinning units, optional up to 408 spinning units with wear-protected, steel-sheathed, high-modulus carbon fibre yarn guide rods

– Cylindrical 230 to 300 m/min

– Tapered 195 to 255 m/min

Yarn guide traverse

– Cylindrical 147 to 155 mm

– Tapered 147 to 150 mm

– Traverse displacement is infinitely variable from 0 to 4 mm

– Anti-patterning through periodic change of yarn guide motion

Waxing device *

– Wax roll continually driven.

– A collector prevents any accumulation of wax particles in the Corobox area

Stop upon reaching the yarn length or the package diameter

– Length measuring device for the production of

packages with defined yarn lengths or

– Mechanical stop when the preset package

diameter is attained


– 1 to 4 Coromat units per machine *

– Digital control with EIS Event Identification System for automatic, sensor-monitored piecing and package doffing with travel optimisation –- Cleaning head for mechanical and pneumatic cleaning of rotor and spinbox, navel and doff tube – Digital optical piecing check

–- Tube magazine for selective feeding of 315 or 265 empty tubes. Automatic discharge at the push of a button

–- Flowing package doffing by presetting a tolerance yarn length to increase productivity

Suction system

– EVA Electronic Vacuum Adjustment for electronically controlled constant spinning vacuum

– Spinning vacuum 60 to 95 mbar (IDS)

– Yarn residues, waste and fibres are collected separately in a two-chamber system

– Possible connection to central waste disposal systems *

– Spark detector


– Input of spinning parameters via touch screen operator panel

– Evaluation of data by Informator

– Representation of data on screen or via a printer

Corolab XQ and Corolab XF

Digital Technology *

– Digital sensors Corolab XQ for the registration of yarn diameter deviations at every spinning position

– Digital sensors Corolab XF for the registration of yarn diameter deviations and foreign material at every spinning position

Fancy yarn device Fancynation *

– Single-motor sliver intake SDSI Single Drive Sliver Intake, FancyBoard, control software and Informator interface

– FancyPilot basic software for creating fancy yarns – FancyControl software for online control of effects – FancyOasys Gold software for extended 3D


– FancyProfile software for measuring effects at the yarn profile

– FancyLink software for scanning foreign yarns and generating the fancy control data records

Spinning cans

Spinning can dimensions, round cans: Diameter 457 mm (17,5“)

(two rows)

530 mm (20“) (three rows)

Height 900 mm to 1,200 mm

(36“ to 48“)

Spinning can dimensions, rectangular cans:

220 mm width x 970 mm depth x 900 to 1,200 mm Height (1,070 mm when using can supports)

Automatic package removal systems *

–- Removal systems such as e.g. single palletizer or Autoflow

– Distribution by Neuenhauser Maschinenbau
GmbH & Co. KG, Neuenhaus, Germany

* Option




The three main aspects of monitoring the mill is Textile, Electrical & Mechanical. Presently most of the mills have concentrated on Textile associated savings etc. Now if they concentrate more on Electrical Energy input to machines and their Mechanical Maintenance by Predictive and condition Monitoring, we can derive maximum productivity with minimum losses by directing right energy inputs to machines.

· Electrical Distribution – Now the priority to the industry is to concentrate more on KVA than KW and we need to do first achieve PF around 0.8 + at load end motors using capacitors. To assess the electrical distribution losses, PF at the load end is the best practical tool. Please look into your PF at the SSB and at heavy load motor terminals.

Thermal imaging of your Electrical distribution network up to the motor terminals and alignment related hot spots on load end can give around 2 % savings & increased production due to correction at load ends later. The symptom of distribution losses at the Electrical Incoming and at the load end is the HOT SPOTS only measured by low cost Thermal gun & high cost Imaging.

The Infrared gun (cost Rs.3000 +) only measures thermal parameters like abnormal temperature, temperature gradient, etc this speedy assessment is a quick tool to diagnose all abnormal Hot spots and warns you about the impending breakdowns priorly in the electrical side and in the mechanical side in the running machines.

Electric Motors – Please concentrate on your motors up to 10 HP motor where you’re per hour loss is around 2 units. These motors lose up to 35 % on losses where as above 10 hp motors lose around 15% .Focus at Pyramid Bottom

A conventional or standard motor running at 50 % loading is operating at 70 % plus efficiency and where as the Energy Efficiency motor at 50 % loading less than 90 % and almost we get difference in efficiency of around 15 %. This is Huge Loss we face now with our existing motors and how efficiently we have loaded motors?

The mills are losing heavily now at this lower speeds due to hotter motors. More it is cool, more is Efficient. Active ventilation and right lubrication is the focus area now to reduce motor losses & improve its output

Running ring frame main motors on auto delta Star mode gives savings around 5 to 10 %. Now the conditions are that instead of 18000 rpm now only 12000 rpm running say and the loading is around 30 to 40 % level only. To protect whole circuits by providing Fool proof Electronic Overload & winding protection relays.

A standard motor operated at an average half the load – its efficiency increases around 4 % when operated at 400 volt plus instead of 440 volt especially at night, in the industry with out OLTC Transformer

Energy Metering – Now in the market, branded 3 phase 4 wire panel meter (cost Rs.2000 +) Worth trying it! Our rational, national, logical thinking is to invest first in this meter before running the motor above 10 HP. This Rs.2000 /- investment is a tool to assess how much you are lose in your

10 HP motor like say Rs.4000/- per month due to difference in efficiency say from 75 to 90 % Metering motor helps you to know your motor working better for you or not!

In the market, clamp on power multi function meter (cost.9000 +). When EB is charging the industry in KVA, KW, PF then we should be in a position to measure the above instantaneous power parameters of individual equipments & account for total EB consumption.

The cumulative measurement using the 3 clamps simultaneously and a 3 phase 4 wire multi-parameter power Meter gives indication of production health i.e. productivity (cost Rs.18000 +) Big mills also need one, instead of keeping only one lakh worth Power Analyzer & keeping in shelf for months. For Small mills, this is ideal tool to study power in Doff cycles for various counts & speeds etc

Our spinning mill is an alignment oriented industry. All our loads are tangentially coupled to motors. The production is not steady due to misalignment inside machines. One of the reasons we must measure both KWH, and KVAH is that PF is varying to loading patterns. Hence when doing Doff study with the above meter, the above parameters are important to know the demand from the load in terms of KW, KVA.

Compressed Air System – In the Compressed air header ring main distribution Tail end Air receiver at can give savings around 10% in power, since air receiver slows the air velocity less than 6 meter per sec and does not create artificial demand. So pressure gauges at each tail end of distribution will show us daily the pressure drops in system.

Humidification Plant – Generally the roof heating by solar radiation causes 50 % of the heat load in any premises. Hence attic Ventilation is low cost & preventive compared to high cost of cooling of equipments & premises under attic.

In the Exhaust fans of AC plants, Pressure die casted blades of weight 15 kgs instead of the existing gravity casted blades of weight 35 KGs in the Exhaust fans will bring down the power consumption by 20% without
Compromising static pressure across the air system and maintaining the same flow rates inside the premises.

Some of the mills do cost cutting by not running exhaust fans. This is not healthy sign of working. If at all you want to save power, clean the air filters in the return air exhaust frequently & reduce restrictions in line.

Textile spinning mill is an air operated industry; we need air to push and pull the raw material from input end to output end of mill. Also we need air to comfort the yarn to enhance productivity thro Humidification. The same air is needed now to remove the waste from the main product in different stages thro AWACS. Hence portable anemometer (cost Rs.3000 + ) is a must to measure air velocity at humidification fans, supply diffusers, return ducts, air movement across hot spots, exhaust passages, attic ventilation.

In the Textile mill AC plant water circuit, we can do ring main distribution and loop all the top blind flanged ends of the vertical sub headers back to tail end of main discharge header of pump. This ensures in the long run, no choking of nozzle and all nozzles get equal pressure & flow of water. This is power saving too. Please install pressure impulse line at pump discharge and fix pressure gauge at the outside of plant so that daily pressure variations is seen to know nozzle plugging & pissing, filter blockage and spray dwell time.

Raw edged inner toothed belt gives saving of 3 to 5 % in belt driven loads from motors. This is easy to do today, can be done quickly and easily, than to think of replacing flat belts a year later. Definitely flat belt gives savings but installation difficult?

D.G.set efficiency -The genset sub systems like air, fuel, cooling and lubrication to be individually looked into for better maintenance. Because we get around one third of Kcal output as Electricity for 1 liter of Diesel. Since efficiency of electricity generation from our genset is poor, definitely there is more scope for better UPL.

The maximum Demand Controller fitted to DG set will help us to set & get max units per liter of diesel. Care is taken on genset air intake temperature, pressure drop, exhaust temperature & pressure to optimum level. Ducting out air intake with nylon pre filter, and ducting out heat exchanger exhaust is done to keep house cool. Taking care of its ageing factor & KVA rating, Higher the loading of genset, better is the UPL.

Good House keeping (visible! & Invisible!)- Of the nearly 20%
saving in energy studies have shown at 5% savings come from Good House keeping .5% comes from conventional technology. And 10% comes from Innovation from the work spots only. The good or bad things happening to us cannot be from outside but it generates from inside only. Good house keeping practices inside & outside the machines is only the ideal way of cost cutting exercise available now.

By energy conservation in the industry, we try to recover the losses which go as waste. By Energy Measurement, we draw a line between Avoidable and Unavoidable Losses and plan to minimize same. So Measurement is the first step to Conserve Energy. The mill M.D. / management have taken the initiative to buy energy efficient equipments. This is half done only. If they give thrust to efficient running of the machines & focus on the invisible electricity losses in the daily routines, then definitely their operating profit margins can improve drastically.

MLM & MLA can only help the industry now. MLM – Micro Level Monitoring & MLA – Macro Level Analyzing of our existing machines power & energy parameters is the need of hour now. The industry manager finds it difficult to meet the ends, the cotton & yarn prices. But if he regulates & minimizes the power consumption of each machine he will be delighted to his margins are under his control and improves more.

The major initiative towards ECON in mills, what we are concentrating now is that we need to measure the Energy inputs (Electricity, fuel oil, water and Air inputs) fed to the mill and that how they are affecting the UKG. There is considerable amount of cost saving in the mill if we switch over from breakdown maintenance situation to a Condition based monitoring & control of the machines & utilities. That is we do not allow the machines to break down at all.


Spinning vacuum on the Autocoro 312

Unique air flow system offers all-round potential ..


The suction system integrated into the end frame of the Autocoro 312 has been completely redesigned and its air flow system optimised. Its special components are a fre­quency-controlled fan and an electronic spinning vacuum ad­justment system – Electronic Va­cuum Adjustment, EVA.

EVA ensures a constant, automat­ically adjusted spinning vacuum. It guarantees optimum running be­haviour and a high yarn quality, saves energy and thus helps to reduce yarn production costs.

The frequency controller adjusts the fan speed automatically, ad­vancing the Autocoro 312 a size­able step closer to the vision of self-regulating processes.

Without adjustment – as on other
rotor spinning machines – the
spinning vacuum decreases con‑

tinuously. To achieve an accept­able average value, it is often set higher than necessary and the drive is frequently oversized.

The vacuum level required de­pends on both the raw material and the type of rotor. Manmade fibres and small rotors, for exam­ple, require a higher spinning vac­uum than cotton or large rotors.


This is the case in principle on every rotor spinning machine.

Less energy, same output

The suction system for generating the spinning vacuum is one of the principal energy consumers on any rotor spinning machine, accounting for 25 to 40 % of the total energy requirement depend­ing on the application. Reducing the energy consumption thus offers huge potential savings.

Some spinning mills are still set­ting a higher vacuum even now than is technologically necessary for textile production. Applied in conjunction with an oversized drive, this incorrect setting in­creases operating costs consider­ably.

On the Autocoro 312, the spinning vacuum can be set to the mini­mum value at which a raw materi­al can be spun economically and technologically.

This yields an energy saving of 1.5 to 7.4 kWh per machine, or more than 60,000 kWh taken over an entire year. The spinning mill saves up to 30 % of its energy costs rel‑

ative to the individual spinning units and compared with previous Autocoro generations. The advan­tages of a controlled, infinitely ad­justable suction system are thus obvious compared with conven­tional systems.

The machine’s power consump­tion is influenced by the air resist­ance in the trash collecting cham­bers as well as the spinning vacu­um. The design of the collecting chambers on the Autocoro 312 has been optimised with regard to the air flow so that the air resist­ance – and therefore the power consumption – is less than on con­ventional rotor spinning machines, even when the collecting cham­bers are full.

Quality and efficiency go hand in hand

With EVA, the quality of the yarn remains consistently high over a long period, even when the spin­ning vacuum is low. This is illus­trated by the following practical example from the USA. Knitting yarns of 100 % cotton were spun at the maximum productivity level. The yarn quality proved to be unchanged with a reduced spin­ning vacuum and the number of clearer cuts remained at a low level.


Maximum productivity thanks to consistent spinning conditions

The view is often taken in practice, based on experience of earlier rotor spinning machines also, that an increase in the spinning vacu­um improves machine running behaviour.

In the American spinning mill, the Autocoro 312 with EVA, operating with a spinning vacuum varying between 60 mbar and 100 mbar, proved that a high level of spin­ning stability and productivity is attained even with a low spinning vacuum.

Increasing the vacuum beyond the value of 60 mbar that is techno­logically sensible in textile produc­tion had scarcely any influence on the productivity of the Autocoro with a Coromat on each side of the machine. Fluctuations in the effi­ciency rating were basically due to intervention by the machine oper­ator to change the cans and elimi­nate red light events.

User-friendly technology to con­serve resources

EVA and the new collecting cham­bers also offer a host of advan­tages for spinning mill staff. The desired vacuum is set easily at the Informator and is infinitely adjust‑

able to take accurate account of the different applications and spin­ning component configurations.

The greater capacity of the trash collecting chambers markedly extends the cleaning intervals, making the work of the machine operator considerably easier with regard to trash-laden raw materi­als in particular. Cleaning intervals are frequently doubled in practice, and are even tripled for some applications compared with previ­ous Autocoro generations. An­other advantage is the automatic warning system that alerts the machine operator when the cham­bers have to be emptied, thus pre­venting overfilling of the collecting chambers.

As an alternative to manually emp­tied trash collecting chambers, the Autocoro 312 can also be linked up to a central system.

Flexible solutions for versatile applications

Every spinning mill always endeav­ours to use the raw material with which it can produce the desired yarn most economically. On the other hand, the choice of raw material is determined by the pur­pose and desired character of the yarns. Fibre parameters such as crimp, length, friction and trash content make different demands in principle on the spinning vacu­um. With EVA, the Autocoro 312 offers the flexibility to ensure opti­mum spinning conditions at all times. This benefits both spinning mills that process the same lots over a long period and those that perform frequent lot changes.

The Autocoro 312 with EVA offers excellent opportunities to tailor economy and yarn quality opti­mally to the demands of the mar­ket.

The drive capacity is rated such
that it achieves optimum efficiency


on the one hand and on the other guarantees smooth operation even for extremely demanding applications. The Autocoro 312 is thus the first rotor spinning machine to deliver the same pro­ductivity and quality at an altitude of more than 4,000 m as it does in the lowlands, even on very long machines.

Over 400 Autocoro 312 machines with Electronic Vacuum Adjust­ment are already operating in numerous spinning mills world­wide. Practice has shown that the suction system is essentially re­sponsible for the enhanced per­formance of the new generation of Autocoro machines compared with their predecessors.


— constant spinning vacuum over a long period

— energy saving of up to 30 %

— consistent yarn quality

— a high level of machine produc­tivity

— efficiency at all installation alti­tudes

— less work for the machine oper­ator

— flexibility thanks to simple oper­ation


Controlling the cost of production at optimum level is one of the essential requirements for the spinning mills to compete successfully in the market. Hence, mills are expected to initiate suitable measures such as profitable product-mix, higher productivity, modernisation of machinery and cost control to improve profitability. SITRA has been offering consultancy services to mills to reduce input costs without any major investment. After a thorough study, the findings highlighting the expected savings in various areas such as waste reduction, improvement in labour and machine productivity and reduction in packing materials cost are submitted to the mills.

Five years ago, SITRA brought out a Focus (Vol.20, No.3, September 2002) on case study of a spinning mill, in which suggestions were offered to reduce the input cost. The present Focus covers the case study of another spinning mill, in which measures for cost reduction have been offered.

2. Profile of the mill

It is a 20 years old unit with an installed capacity of 36000 spindles and 1380 rotors. The mill is equipped with hi-tech machinery in all the departments. It has been producing 100% viscose, 100% polyester and polyester/ viscose blended yarns.

3. Areas identified for cost reduction

The summary of the mill’s performance and suggestions for cost reduction are given in the following pages.

3.1. Production rate

Production per spindle in ring frames

The overall production per spindle is 101 g per 8 hours ( 40s) which is about 20% lower than the standard of 125 g. The count-wise production per spindle for major counts is given in Tables 1 and 2. The standards given in Tables 1 to 3 are based on the experienced values.


The lower production rate in both the Units is mainly due to: – lower spindle speed (by 10%).

– higher tpi (by 6%) except 100% polyester counts and – lower machine efficiency (by 4%).

The average end breaks are low at 14 per 1000 spindle hours (standard: 20).

The overall pneumafil waste is low at 0.6% (standard: 1.0%). Hence, there is a good

scope for either increasing the spindle speed or reducing the tpi.

The lower machine efficiency is mainly due to unnecessary stoppages of ring frames such as waiting for/after doffing, more time taken for doffing, etc. By improving the work practices of doffers, the mill can reduce the unnecessary stoppages of frames.

Production per rotor

Table 3 gives count-wise production per rotor achieved by the mill.


The production per rotor is about 40% lower than standard in 30s V and 35% lower in 20s PC counts. The lower production rate is mainly due to lower rotor speed (by 33%) and higher tpi (by 8%). Since the end breaks per 1000 rotor hours are less than the standard at 90 in 30s V and 65 in 20s PC counts (standard: 100), the mill should explore the possibilities of increasing the rotor speed. Alternatively, the mill may also try to use lower tpi.

Scope for improvement

There is a good scope to increase the overall production per spindle by about 7% (2% by improving the machine efficiency and 5% by increasing the spindle speed) under the existing conditions. With this, the overall production per spindle (adj. to 40s) would increase to 108 g per shift of 8 hours. In the case of rotor spinning, there is a scope to increase the rotor speed at least by 5%.

The mill should replace the existing 42mm diameter rings with 38mm diameter rings in some of the ring frames so that counts above 24s can be run at higher speeds. By improving the machinery maintenance practices, the spinning performance can be expected to improve further. This would enable the mill to maintain the breakage rate and pneumafil waste within the standard even at the increased spindle speeds.

Towards increasing the machine efficiency, the mill should ensure that unnecessary stoppages of ring frames are avoided. For this, the work practices of the doffers must be improved.


Savings due to 7% increase in production per spindle would be about Rs 30 lakhs per year and 5% increase in production per rotor would be Rs 2 lakhs per year.

3.2. Machine utilisation

The machine utilisation maintained by the mill during January to July 2007 ranged from 90% to 98% in Unit 1, 89% to 97% in Unit 2 and 56% to 86% in rotor spinning, the average being 94% in Unit 1, 93% in Unit 2 and 76% in rotor spinning. The causes for the loss in utilisation are given in Table 4.


The major causes for the loss in machine utilisation are: planned stoppages, want of orders and raw material shortage. The number of counts and also the type of yarns manufactured are high in both ring and rotor spinning which is one of the major reasons for the planned stoppages. The mill should strengthen the marketing department and ensure that the required orders are received.


How to save Energy in Textile Mill ?

energy-saveElectricity Lost between the Cup & the Lip in the Textile Mill

We find now in the textile industry, the precious Electricity is dissipated partially in the form of heat in stages from the Electrical distribution network to the textile machines & textiles’ utility. The mill is silently losing energy heavily and the productive output of the mill is coming down. So to improve the output to meet the production targets, the manager is overloading the machines and thus accelerating the ageing of machines. If we improve & make healthy the operating parameters of the active & passive sub systems of the mill, we can achieve steady and gradual increase in growth rate of production and the losses reduce automatically.

Electrical parameters pro-active to production:

· . Presently the textile manager gives priority to its production only ie using the electrical utility to assist only the production and not to record its electrical health. So both instantaneous and trending measurements are important. The low cost clamp on power meter is costing less than Rs.9000, which has become affordable now.

· The instantaneous measurement-using clamp on meter gives an indication of machine health. The cumulative measurement using the same clamp on meter cum analyzer gives indication of production health ie productivity. So the electrical utility should ensure first its best maintenance and equally concentrate to assist textile production in finding UKG per machine.

· In India, Large Scale process industries are contemplating to continuously use the smallest infrared thermal imager costing in lakhs of Rs. to find out where they are losing energy and where the safety is failing in the plant creating fire & safety hazards. The textile mill nowadays needs to resort to use the basic infrared gun to pinpoint where the energy is lost in the mill. This costs less than Rs.5000 only, but the user can take numerous readings using the same daily.

No-load characteristics during Motor Service:

· The open shaft speed, power on no-load before and after the service on the motor on any machine say like ring frame etc. shows the improvement in effciency after servicing the motor. So the service crew must analyze the motor characteristics like electrical parameters of input & output ie the speed on the shaft before taking the motor for service and after service.

Bearing only is protected or motor made comfortable?

· For a motor of 24 hr 365 day running nature in a ring frame like application. The motor bearings facing a temperature of 100 * C and above due to non-stop running of the motor. They definitely need a better lubricant grease ie high temperature grease as well it should withstand the mechanical shear stress capability. After all the motors are belt-coupled to the load and the bearing has to withstand the tangential stress. Hence the grease applied should be right in quantity and more stringent in quality and practically speaking, the grease must remain in shape and color as left before in the previous servicing.

· In many mills, we find the maintenance crew use Multipurpose or all-purpose grease especially for ring frame motor applications. After a month onwards, we find the grease has dried partially in the bearing, or oozed out of the bearing very early. This is a very unhealthy sign. Here the mills lose energy in the motor itself before transmitting to the load condition. That’s why many a motors are running hotter even at low spindle speeds and eating the profits of the mill.

· Here we find in some other mills, the extra cautious user sees to it the bearing is protected at any cost and uses high quality, long life, and heavy cost lubricant grease. But we must bear in mind that greasing the motor

bearing is not to protect the bearing only, it should catalyze the smooth working of motor at less power cost ie its lubricity is more important in comforting the motor and not its sturdiness or long life.

· Practically what is happening in many mills is that, many mills are using Rs.80 / KG grease for motors. But some mills spend even Rs. 800 / KG and much above rates for special grease to comfort the motors. Let us think about the losses increasing in squeezed motors and comfort the motors from now onwards for better motor efficiency.

· The motor user must think that his motor running with dried or heavy viscous, or oozed out grease in the bearings is like the bullock cart gliding up the upward slope road. If the same motor is lubricated at right interval with right quality & quantity then it is like the same cart gliding down the downward slope road. Hence the prime mover greasing is given more priority, when compared to the load end greasing.

Electricity is made useful to the mill:

· The Electrical man responsible in the mill must measure and record the details of the power input supplied to each of the motors in the mill like KVA, KW, KVAR, PF, I. But the same electrical man must be motivated to do the following routines intermittently: –

1) To reduce the power input to each of the motors for the given load.

2) To coordinate with the production to reduce & sustain the motor load

3) To run the motor at the band of its peak efficiency.

4) To find the optimum load ie spindle speed for the given count of yarn.

5) For the given count, do the frame-to-frame analysis to study the Electrical parameters on load,

6) Create bench mark in electrical parameters with cross reference to all the Adjacent similar frames

7) Use the specs given by the motor & machine manufacturer or use industry Segment reference

Voltage drop Losses in each motor circuit:

· The break up of T & D losses prevailing in the Indian industry indicates that the losses are much less and steady in transmission compared to losses occurring in Distribution. Also the distribution losses are varying with respect to time, load and other circuit parameters. Hence frequent monitoring and curtailing the distribution losses is part of daily routines of the Electrician in the mill.

· For example, we find in mills, that the voltage drop in 415 volt arm from the electrical room to local distribution loads is less and constant. But we find the voltage drop is more from the SSB to the motor panel; and still more losses occur from the running delta contactor of motor panel to the motor terminals. This is clearly evident and an avoidable loss in the case of ring frame applications running with 34 KW motors and above.

Few Rs. More in Electrical panel gives much more savings:

· From the electrical distribution, we see lot of network losses. First we check again the proper cable lugs of correct metal and size is used in machine end terminals. We see joints, terminal connections getting loose, heated up, damaging the sheath, terminal strip etc and motor goes for single phasing & load unbalance results. In some mills, still the round type closed terminal strips are used even for motor power connections. Here the flat type open terminal strips of suitable higher current rating is a must to replace. The contact surface area will be broader, mating of lug with terminal is fastened broadly and this reduces risk of unbalance.

· In a given panel it is easy for the electrician to check on line with the voltmeter. He checks that the voltage drop on the same phase between incoming & outgoing wires across the switchgears etc components in the panel is very much less than a volt. He can have cross-reference with the other two phases at the similar points in the panel. Nowadays, the electrical power loss in the panel is going more and goes unnoticed often.

• Here is where the electrician makes use of the infrared gun conveniently and quickly to assess the panel health. The basic principle behind infrared imaging on the electrical systems is that high resistance usually indicates the electrical faults. When you pass a current through a high resistance point in an electrical system, heat is generated at the point of resistance and spreads.

· Normally in any electrical system, when the fault occurs, the first symptom is abnormal heat rise. The second symptom that occurs only next is the change in voltage levels, & the current levels. Hence it is the alert electrician who first finds the fault (that time, the fault is also minor) before the next stage where the fault leads to electrical parameters change and consequently the electrical breakdowns, fire, unsafe hazards etc.

· The mechanical maintenance man also alertly finds first the abnormal heat especially in alignment or bearing or coupling. Before the next bigger fault like vibration, bearing failure, belt problems etc happens he is prepared to prevent and rectify the fault before becoming from minor fault to major breakdown resulting in loss of machine available to production.

The Existing motor is Efficiently working or not?

· We know for example on a 34 KW ring frame motor, not all the input power is converted and transmitted to output shaft, due to the loss of energy conversion and transmission. So to reduce the losses, which exhibit outside the motor as heat in the fins, we have to ensure forced cooling positively. After all, the motor manufacturer has enclosed the motor cover with fins so as to quickly dissipate the heat from the motor. So let us take care to remove the fluff, which falls, & covers the motor fins and allows the motor to breathe and not starve. In some mills, the user fixes a netlon mesh on the fan cowl especially in short frame motor so that he clears the fluff hourly which sits on the mesh and ensures the motor gets good throw of air surrounding the motor.

Motor cooling by hot / cool surrounding air?

· Here in mills in the ring frame area, we notice that the motor itself runs hot and the motor is washed with hotter pneumafill air. This is analogous to the man who sits in the room below the open terrace in the building feels hot due to the summer heat. He switches on the ceiling and now he finds himself more hotter, to make the things worse. Similarly, the hot ring frame motor becomes hotter on motor washing with hot air. Hence the mill should act upon this problem to provide relatively cool ambient air to force cool the motor.

· We have to take care of the motor with positive active ventilation all over. For the same, we ensure strong axial air throw along the ribs of motor so the overall surrounding temperature of the motor comes down. Now the motor breathes normally with the shrouded fan effect at its one end and its efficiency improvement is seen in the long run. The loss to the motor due to this retrofit is very minimal, but overall efficiency of the motor improves due to the above force cooling of fins & the motor itself.

Few watts loss yield better motor productivity?

· As per PCRA booklet on motors, one Motor manufacturer uses a cast iron impeller instead of plastic fan in his EE motor design for forced cooling off the ribs of motor; and the same manufacturer uses plastic fan in his Standard motor. What we must understand is that few watts more loss at non-drive end will definitely improve overall health & efficiency. Active ventilation and forceful throw across motor fins will show few more watts input but in the long run this reduces the losses of the motor

Loading Vs. Efficiency

· Generally speaking we study the Efficiency of any machine and then only decide its optimum loading. As an analogy we ask ourselves whether we eat to Live or Live to Eat. If we are Eat to live people we eat for us and productive to others. On the contrary if we live to eat, then we are living on earth only to eat for ourselves only & we are unproductive to others. Similarly we study the ring frame motor load & no-load characteristics and decide whether the motor serves the mill or a liability to the mill.

• We try to load the motor in healthy way such that the full DOFF position is attained at the 90 % loading maximum of the motor and not more than that. In some mills, motors work around 100 % capacity and we find motor struggles to maintain the output due to slippage. It is like a man starting to run like 100 metre dash in the cross-country race 10 km run he has participated. He gets tired due to his quick burst of running but he could have achieved with sustained steady running from the start. So we have to run the motor at its optimum capacity for better benefits in the long run. We have to check the motor characteristic with the manufacturers’ test certificate. We first check how the motor can run its optimum loaded condition COOLY and the rate of temperature rise is gradual.

• In mills, where condition based monitoring have become daily routines; the electrician checks the power factor of ring frame motor often (in the capacitor cut-off condition at motor end). This higher PF at empty and full DOFF positions is one of the symptoms of motor and alignment health. So he shrewdly diagnoses the motor condition inferentially. We have to see that the PF index is steady over years of running of motor right from the manufacturer’s test certificate at the time of commissioning till date. If the motor by itself can maintain a PF of 0.8 and above from empty DOFF and above, it is one of the good signs of running well.


The textile mill must adopt a stage-by-stage approach on regulation of the mill ‘ electrical inputs. The stage wise regulation in voltage, power factor (nowadays the APFC panel finds partial usage in spinning mills) gives the mill immediate payback The textile manager is now fully concentrating his attention in yarn input and output of the mill as the electrical inputs at the load ends have now been regulated, metered, steady and safely entering at the textile machines.