(Reaffirmed 2004) IS : 7703 ( Part 5 ) - 1987 Indian Standard METHODS OF TEST FOR CONTINUOUS FILAMENT POLYESTER POLYAMIDE PART Physical Chairman DR V. SUNDARAM AND FLAT YARN PERCENTAGE Committee, TDC 1 5 UNEVENNESS of Test Sectional Methods Retresenting Cotton Technological Research ( ICAR ), Bombay Laboratory Members DR V. G. MUN~HI ( Alternate to Dr V. Sundaram j AQRICULTURAL MAEKETlNo Directorate of Marketing & Inspection ADVISER TO TUB GOVE~~VMENTOB of Agriculture ), Faridabad INDIA SHRI ( Ministry & Disposals A. T. BASAK SHRI D. K. NANDY t. Alternate ) SHRI B. N. BA~U Office of the Jute Commissioner, Calcutta Indian SHRI C. BHATTACHARYA Ltd, Petrochemicals Corporation Vadodara SHRI H. C. BHATIA ( Alternate ) National Test House, Calcutta SHRI P. B. CI~AERABORTY SHRI B. CHAUHAN Man-Made Textile Research Association, Surat SRRI D. J. Smarr ( Altunate ) SIIRI S.S. GHOPRA Export Inspection Council of India, New Delhi SHRI G. MITRA ( Alternate ) ,National Rayon Corporation Ltd, Bombay GENERAL MANA~ER(~PICRATIONS) SHRI D. S. NADKARNI ( Alternate 1 SHRI R. GHOSH Ministry of Defence ( R & D ) SHRI S. S. BA~GA ( Alternate ) DR V. G. KAMATH Nirlon Synthetic Fibres & Chemicals Ltd, Bombay DR A. R. MUEHE~~JEE ( Alternate) SHRIMATI A. KAPLESH Silk & Art Silk Mills' Research Association, Bombay SHRI M. R. PARANJAPE ( Alternate ) ( Continued on Pane 2 ) Directorate General of Supplies ( Inspection Wing ), New Delhi 0 BUREAU Copyright 1988 OF INDIAN STANDARDS This publication is protected under the Indian Copyright Act ( XV of 1957 ) and reproduction in whole or in part by any means except with written permission of the publisher shall be deemed to be an infringement of copyright under the said Act. IS t 7703 ( Part 5 ) - 1987 ( Continuadfiom pugs 1 ) Representing Members Ministry of Defence ( DGI ) SEXRI M. K. MAM SHRI P. C. BASU ( Alternate ) Intexa India, Bombay DR B. R. MANJUNATIZA DR (SHRINATI) G. R. PHAL~UMANI Textiles Committee, Bombay Bombay Textile Research Association, Bombay SHRI M. RADHAKRXSENAN SHRI A. V. RAVIXDRANATEAN ( Ah6rnate ) Wool Research Association, Bombay SERIMATI G. P. RANE Indian Jute Industries' Research Association, DR S. R. RANQANATHAN Calcutta DR U. MUEHOPADHYAY ( Altdrnate ) Limited, Textile Corporation National SHRI M. S. RAYCHORE New Delhi South India Textile Research Association, SHRI K. N. SESHAN Coimbatore Raymond Woollen Mills bmited, Thane DR G. S. SINGE SHRI J. K. BANERJEE ( Alternate ) Textile India Research Bureau, Bombay SHRI C. S~VARAYAN Central Silk Technological Research Institute SHRI T. N. SONWALI~AR ( Central Silk Board ), Bangalore Office of the Textile Commissioner, Bombay Dx T. V. K. SRIVASTAVA SBRI S. P. KALA ( Alternate ) Ahmedabad Textile Industry's Research AssociaSHRI T. A. SUBRAXANIAN tion, Ahmadabad M Best Cotton Rope Manufacturing Co, Bombay SRRI M. G. THANAWALA Punjab State Hosiery & Knitwear Development SHRl J. N. VOnRA Corporation Ltd, Chandigarh SHRI P. T. BANBHJI ( Alter&e ) Director General, BIS ( Ex-ofFcio Member ) SHRI R. I. MIDHA, Director ( Tex ) ( Secretary) Subcommittee for Physical Methods of Test for Man-Made `Fibre Textiles, TDC 1 : 20 Convener DR V. G. KAMATH Nirlon Synthetic Bombay Fibres & Chemicals Ltd, Mcmbcrs DR A. R. MUKHERJEE ( Alternat to Dr V. G. Kamath ) Directorate General of Supplies & Disposals SHRJ A. T. BASAE ( Inspection Wing ), New Delhi SBRI P. K. BASU ( Alternate ) TCA ( Tyres Division ), Calcutta SHRI B. BHATTACHARYYA SHRI D. M. CHATTERJEE (Alternate) Indian Petrochemicals Corporation Limited, SHRI C. BRATTACHARYA Vadodara DR U. DAYAL ( Alternate ) ( Continusd on page 9 ) 2 IS : 7703 ( Part 5 ) - 1987 Indian Standard METHODS OF TEST FOR CONTINUOUS FILAMENT POLYESTER POLYAMIDE FLAT YARN PART 5 UNEVENNESS PERCENTAGE AND 0. FOREWORD 0.1 This Indian Standard was adopted by the Bureau of Indian Standards on 30 September 1987, after the draft finalized by the Physical Methods of Test Sectional Committee had been approved by the Textile Division Council. 0.2 In the preparation of this standard, due weightage has been given to the testing practices followed in this field. 0.3 Assistance has been derived from ASTM Designation D 1 425-81 Standard Test Method for Unevenness of Textile Strands Using Zellweger Uster Capacitance Testing Equipment, issued by the American Society for Testing and Materials, USA. There are some other instruments which are in use in the country for determining unevenness percentage but the correlation between the results obtained by different instruments requires to be established. This work is now being taken up through inter-laboratory trials and the standard would be reviewed thereafter. 0.4 This standard forms a part of the series of standards on `Methods test for continuous filament polyester and polyamide flat yarn'. of 0.5 In reporting the result of a test or analysis made in accordance with this standard, if the final value, observed or calculated is to be rounded off, it shall be done in accordance with IS : 2-1960*. 1. SCOPE 1.1 This standard ( Part 5 ) prescribes a method of test for determination of short-term variations in mass per unit length ( unevenness percentage ) of continuous filament polyester and polyamide flat yarn. *Rules for roundingoff numerical value3 ( reoiscd ). 3 IS :7703 ( Part 5 ) - 1987 1.2 This method covers the indirect measurement of unevenness of the flat yarn by means of continuous runs on a suitable Uster unevenness The direct procedure for measuring unevenness by testing instrument. cutting and weighing short lengths of a flat yarn is not covered by this standard. 1.3 Low twist filament while testing. 2. TERMINOLOGY 2.1 Unevenness - Variation in the linear density of a continuous or a portion of a yarn ( see also coefficient of variation unevenness, deviation unevenness ). yarn mean yarns should be tested after the yarn is pretwisted 2.2 Coefficient of Variation Unevenness, CV Percent - The standdard deviation of the linear densities over which unevenness is measured expressed as a percentage of the average linear density for the total length within which unevenness is measured ( see also unevenness, mean deviation unevenness ). 2.3 Mean Deviation Unevenness, U Percent - The average of the absolute value of the deviations of the linear densities of the integrated lengths between which unevenness is measured and expressed as a percentage of the average linear density for the total length within which unevenness is measured ( see also unevenness, coefficient of variation unevenness ). 2.4 Length Between Lb -The length between which measured, the equivalent of the length of yarn segments direct method of measuring unevenness. unevenness is weighed in a , 2.5 Length Within Lw - The length over which unevenness is measured, the total length of the yarn from which the segments weighed were sampled in a direct method of measuring unevenness. For indirect methods, the maximum value of length within is the tested length from the specific package. 2.6 Unit Length of Instrument, sured between the sensing elements 2.7 Integrator - A device that unevenness or the mean deviation L, - The length any moment. calculates the unevenness. of yarn being mea- coefficient of variation 2.7.1 The term `integrator' and `integration' as applied to textile unevenness testing do not imply integration in the strict mathematical linear or quadration must be carefully sense. The type of integrator, selected depending upon a known irregularity of the material, that is, purely random or purely periodic. 4 IS : 7703 ( Part 5 ) - 1987 2.8 Quadratic Integrator - An integrator that operates continuously unevenness for the time during which it has been active, weight to all portions of the input ( compensated-memory and reports giving equal integrator). 2.9 Linear Integrator - An integrator that operates continuously reports unevenness for a certain, and unchanging, time past. and The input to the integrator immediately preceeding the moment of taking a reading receives greater `weight' than the prior input, and this `weighting' gradually decreases with the lapse of time ( fading memory integrator ). 3. PRINCIPLE 3.1 AND LIMITATIONS A yarn is passed through the sensing device of an Uster unevenness tester at constant speed and a momentary value proportional to the linear density of the yarn is recorded. The Uster instruments are equipped with an integrator that calculates the unevenness automatically and the value is read while the yarn is psssin g through the instrument after 400 m of yarn have been tested. 3.1.1 The variation of one specific unevenness. The method is concerned flat yarn. property, linear with measuring density, is termed the unevenness of 3.1.2 Unevenness is always expressed as between successive lengths and over a total length. When the length between which unevenness is measured ( Lb ) is very short ( 8 mm of yarn ), then reference is often made to short-term unevenness. 3.1.3 Unevenness can be measured by direct method or indirect methods. The direct method consists of cutting and weighing yarn segment of length Lb and is the reference method of determining unevenness. Unevenness testing instruments, as covered in this standard, use the indirect method where unevenness is determined by the measurement of yarn properties closely related to and dependent on linear density. The accuracy of the indirect method and of an instrument utilizing it can be judged by a comparison of the value of unevenness it gives with one obtained by the direct method of cutting and weighing. 3.1.4 The Uster unevenness testing instruments of the yarn which change the capacitance when the plates of a capacitor. measure the yarn those properties passes between 3.1.5 A number unevenness of yarn. of mathematical concepts are used to express the They are all based on the coefficient of variation or its 5 IS I 7703 ( Part 5 ) - 1987 square. There is, therefore, some advantage in using an unevenness testing instrument that gives the coefficient of variation and thereby fits into the general mathematical scheme. 4. APPARATUS 4.1 Capacitance-Type Unevenness Testing Instrument -A suitable Uster unevenness tester using automatic integrator or any other suitable instrument which can satisfy the requirements The instrument shall have the following accessories provided. 4.1.1 Package Holders, Guides, Tension Devices and Take-@ Mechanism Which allow for or assist in, uniform delivery of the yarn at the specified speed without undue acceleration or deceleration and at a reasonably constant tension. 4.1.2 Recorder - To give a permanent chart reco-d of the test details and to depict the unevenness. It is a means to record all unevenness. 4.2 Pretwisting with constant tension material feeding facilities for lowtwist filament yarns to impart false-twist into low-twist filament yarn while it passes between the sensing elements at a uniform tension. 5. ATMOSPHERIC TESTING CONDITIONS OF SAMPLE FOR CONDITIONING AND 5.1 The test sample shall be conditioned to a state of moisture equilibrium from dry side in standard atmosphere at 65 f 2 percent relative humidity and 27 f 2°C temperature ( see also IS : 6359-1971* ) and tested in the same atmosphere. NOTE- When a test sample has been left in such a way as to expose as far as possible, all portions of it to the standard atmosphere for 24 hours, the test sample shall be deemed to have reached a state of moisture equilibrium. 6. PROCEDURE 6.1 Calibrate instrument the unevenness manufacturer, testing instrument as prescribed by the NOTE -Do to testing. not separate the length of yarn to be tested from the packages prior 6.2 Mount the package on a suitable holder, Thread the free end of the yarn through the sensing elements of the tester and through the take-up mechanism. If a low twist yarn is to be tested, pass it through a device imparting false twist. *Method for conditioning of textiles. 6 IS : 7703 ( Part 5 ) 9 1987 6.3 Set the take-up mechanism to yarn speed of 100 m/min or to speed of travel as agreed to between the buyer and the seller. If a recorder is used, set the yarn to chart speed 10 cm/min with test time limited to four minutes. 6.4 Start the take-up mechanism of the tester and recorder, if used. Adjust the controls of the tester to record on the central part ofthe recorder chart or on the central part of the instrument meter or both. 6.5 Turn on the integrator. Test a total yarn length of at least 400 m in one uninterrupted run, unless otherwise agreed .upon by the purchaser and the seller. Record the meter unevenness value. 6.6 Follow the unevenness tester instruction manual for operational procedures not outlined in this method. 7. CALCULATIONS 7.1 The CV percentage and U percentage can be estimated from the chart by converting the line of the record into a frequency distribution. U percentage can also be estimated by the use of a planimeter. Normally, however, CV percentage or U percentage will be read from the integrator ( see 6.5 ). 7.2 If more than one value of CV percentage or U percentage is obtained for individual packages, then calculate arithmatic mean of values of unevenness for each package. 7.3 Calculate packages. the average of CV percentage or U percentage for all 7.4 If required, calculate the coefficient of variation or the standard deviation ( or both ) of the CV percentage or U percentage values obtained for each package. 8. REPORT 8.1 State that the specimens were tested Describe the material or product sampled. 8.2 Report the following information. 8.2.1 8.2.2 Number of specimens tested. Instrument used and type of integrator, if used. as directed in the standard. 8.2.3 Yarn travel speed. 8.2.4 Length of specimen tested. 7 ES : 7703 ( Part 5 ) - 1983 8.2.5 Chart speed or yarn-to-chart calculation, if chart is used. 8.2.6 8.2.7 speed ratio and method of chart Type of setting used, that is, normal, inert or half inert. Atmospheric conditions used, if not standard. obtained standard as CV deviation, percentage or both, or if value of unevenness of variation or 8.2.8 Average U percentage. 8.2.9 Coefficient calculated. 8.2.10 The values of length between Lb and length within L,. put Lb and Ln values NOTE - The preferred way of writing the unevenness is to in parentheses ( Lb, LW ) after CV percentage or U percentage. _&le CV ( 8 mm, 100 m ) to be read as follows: unevenness between `Coefficient lengths'. of variation 8 mm lengths within 100-m 9. SAMPLING 9.1 Samples shall be drawn in accordance in IS : 7703 ( Part 4 )-1981*. with the procedure laid down *Methods Sampling. of test for continuous filament polyester and polyamide flat yarn : Part 4 8 IS : 7703 ( Part ( Continued from page 2 1 Members SHRI M. D. BOKADE SERI P. 5 ) - 1987 Representing National Rayon Corporation Ltd, Bombay Baroda Rayon Corporation Limited, Swat B. CHINOY DR V. D. MEHTA ( Alternate ) National Test House, Calcutta SHRI ANILENDU GIIOSH Modipon Limited, Modinagar SHRI A. K. GOVIL SHRI B. K. GAEL ( Alternate ) Indian Institute of Technology, Delhi PROF V.B. GUPTA DR P. K. HARI ( Alternate ) Century Rayon, Kalyan SHRI M. M. GURBAXANI SHRI HARI DAS (Alternate I Ceat Tyres of India Ltd, Bombay SHRI S. KRISHNAJ&THY J. K. Synthetics Ltd, Kota DR RAMETH KU~AR DR A, K. BHARADWAJA ( Alternate ) Directorate General of Technical Development, SHRI R. P. KAWATRA New Delhi Century Enka Limited, Bombay SHRI V. B. LALL SHRI A. M. BAVADEREAR ( Alternate ) Dunlop India Limited, Calcutta SHRI K. S. LOQANATHAN SHRI A. SIROAR ( Alternate ) Petrofills Co-operative Ltd, Vadodara SHRI B. B. MATHUR Garware Nylons Limited, Bombay SHRI G. V. MEDHI Orkay Silk Mills Private Ltd, Bombay SHRI KAPAL MEHRA Silk & Art Silk Mills' Research Association, SHRI M. R. PARANJAPE Bombay DR (SHRIMATI) G. R. PHALQUMANI Textiles Committee, Bombay DR M. R. MAJI ( Alternate ) Bombay Textile Research Association, Bombay SRRI M. RAbHAKRISHNAN SHRI K. VENKATARAYAN ( Alternate ) Shriram Rayons, Kota SHRI M. S. RANE SHRI V. K. Snnr ( Alternate ) MRF, Madras SHRI G. R. SAN~~ARANARAYANA SHRI A. GEORQEJOHN ( Alternate ) Bombay Tyres International Limited, Bombay SHRIP. G. SA'NT Shri Ram Institute for Industrial Research, SHRI C. P. SIIARDA Delhi SHEI G. V. SIIAI~MA (Alternate ) Goodyear India Limited, Calcutta SHRI D. C.VERMA SHRI P. SURI ( Alternate ) Ministry of Defence ( DGI ) SHRI D. R. YADAV SHRI D. K. SRIVASTAVA ( Alternate ) lNtERNATlONAL Base Units Q4/a/ltity Length Mass Time Electric current Thermodynamic temperature Luminous intensity Amount of substance Units SYSTEM OF UNITS (SI UNITS) Unit metre kilogram second ampere kelvin candela mole Symbol L S A K cd mol Supplementary Quantity Plane angle Solid angle Units Unit radian steradlan Symbol rad sr Derived Quantity Force Energy Power Flux Flux density Frequency Electric Pressure, conductance force stress Electromotive Unit newton joule watt weber tesla hertz siemens volts Pascal Symbol N J W Wb T HZ S V Pa Definition 1 N = 1 `kg.m/sa J = 1 N.m lJ/s 1 V.8 1 Wb/ma 1 1 W = 1 Wb = 1 T 1 S 1 v = 1 Hz = 1 c/s (s-1) =lA/V = 1 W/A 1 N/ma 1 Pa =