Experimental reserches on the yarn tension variation influenced by the ring position against textile spindle specific to ring frames.

Hanganu, Lucian Constantin ; Grigoras, Stefan ; Stirbu, Cristel 等

1. INTRODUCTION

The ring frame represents the main spinning equipment for yarn production and it is the last machinery of the spinning process with its roll to transform the fibres band on yarn by specific subassemblies such as: draft system, wrap and twist mechanism, drive system for textile spindles (Hanganu, 2009). These are dedicated to realize the whole technological process for which the machine was designed. To obtain high quality yarn it is required to consider the interdependence not only between the constructive solutions for ring frame components and their functional parameters but also, the both nature and physics-chemicals properties of the processed fibres as is shown in figure 1 (Hanganu & Loghin, 2010).

[FIGURE 1 OMITTED]

The paper study is focused onto the aspects of yarn tension which are specific for the spinning area of the ring frame. This means mainly a deep analysis of everything that happens with the yarn in correlation with its driver, ring and traveller. The results of this experimental research study offer a database for designers involved in obtaining better constructive solutions for the components mentioned above.

2. TEST RIG

A general schema for the test rig is shown in figure 2.

[FIGURE 2 OMITTED]

There are three main components of the test rig: the drive system for textile spindle, measuring yarn tension equipment and digital oscilloscope. The drive system for textile spindle is basical structured from a textile spindle 1, the ring 3, the traveller 5 and yarn driver 6; this system offers the possibility to rotate the textile spindle between 6000 and 22000 rpm.

Attachment of bank ring and yarn driver has been modified so as to carry out those positions to the time requirements imposed by experimental determinations through micrometer screws 7.

The tension from yarn 2 is detected by the transducer 8 connected with the power amplifier 9 and the final result is displayed on oscilloscope 10.

Component parts 8, 9 and 10 create the possibility of detecting both static and dynamic yarn tensions.

There were created conditions for overcoming the negative influences on yarn tension, of which stated:

--ensuring squareness of the spindle rod towards both spindle bank and ring bank;

--using a ring with minimum deviation from circularity (under 0.01 mm);

--faience yarn driver without slot;

--using a filamentar and uniform yarn;

--rigid assemblage of ring bank;

--yarn winding directly onto the spindle rod to eliminate the influence of tube defects;

--controlled central position between the textile spindle and yarn driver.

With this equipment can be measured both average and maximum yarn tension and allows highlighting the influence of each constructive factor.

3. EXPERIMENTAL DATA

Experimental tests were performed on a textile spindle Texparts--HF 3 type, verified in terms of dynamic response (vibrations) (Hanganu et. al., 2009). Experimental determinations were performed for:

--ring diameter of 42 mm and traveller 11/0 (0,019 g);

--ring diameter of 48 mm and traveller 11/0 (0,019 g);

--ring diameter of 48 mm and traveller 6/0 (0,030 g);

To see the influence of the ring eccentricity towards the textile spindle onto the traveller speed and acceleration, and thereby the variation of yarn tension [DELTA]F, should be carefully considered the traveller movement during a rotation on the ring.

There were imposed restrictions to reveal only the settlement influences of ring eccentric to the spindle, eliminating all factors that could distort the measurement accuracy.

For even more accurate measurements were taken into account and the variation of yarn tension due to vibration of the traveller.

4. CONCLUSION

For a ring seated correctly, without eccentricity, perfectly round, with spindle speed, constant winding radius and delivery speed, it follows for traveler, of course theoretically, constant normal acceleration, constant speed and "zero" tangential acceleration.

In the same conditions as mentioned above, but with eccentric placement of the ring over the textile spindle, the traveller speed and normal acceleration have variations and tangential acceleration can take significant amounts. Consequently yarn tension variations occur, the maximum values of these changes having adverse influence on the frequency of breakage.

Because these values were relatively low, in evaluating the influences of various organs involved in yarn production on the average and maximum value of these tensions, there were have been overlooked.

For this purpose the test rig was adjusted so that it can be highlighted only the tension changes due to traveller, other factors which can influence the yarn tension are eliminated by setting the installation options.

Startly from these results it is possible to take decisions towards better constructive solutions for spinning systems of ring frames.

5. ACKNOWLEDGEMENTS

The authors acknowledge The National Centre for Programme Management (CNMP) from Romania for funding this research.

6. REFERENCES

Hanganu, L. C. & Loghin, M. C. (2010). Oil viscosity influence on textile spindles damping coefficients with main implications in production quality increasing for fibres dedicated to technical textiles, Industria Textila, Vol. 61, No. 1, pp. 31-35, ISSN 1222-5347

Hanganu, L. C. (2009). Contributions to Ring Spinning Frames Dynamics, Proceedings of ModTech International Conference, pp. 287-290, ISSN 2066-3919, Iasi, Romania, 21-23th May

Hanganu, L. C., Loghin M. C. & Stamate C. V. (2009). Specific Aspects on Yarn Tensions Produced During the Ring Spinning Frames Operating, Proceedings of ModTech International Conference, pp. 291-294, ISSN 2066-3919, Iasi, Romania, 21-23th May

Hanganu, L. C., Grigoras, St. & Ianus, G. (2009). Dynamics Of Yarns Produced On Ring Spinning Frames--A Mathematical Model, Proceedings of ModTech International Conference, pp. 295-298, ISSN 2066-3919, Iasi, Romania, 21-23th May

Hanganu, L. C., Grigoras, St., Ianus, G., Stamate, V.C., Borzan, M. & Ionescu, D. S. (2009). Considerations Concerning the Oil Viscosity Influence on Textile Spindles Dynamic Response, Materiale plastice, Vol. 46, No. 1, March 2009, pp. 62-66, ISSN 0025-5289

Tab. 1. Valorile lui [DELTA]F (x[10.sup.-2] N) pentru inel
[empty set]42 si cursor 11/0

 e (mm)
[n.sub.f]
(rpm) 0 0,2 0,4 0,6 0,8 1,0

6000 0 0,316 0,635 0,952 1,271 1,590
7000 0 0,428 0,859 1,287 1,718 2,146
8000 0 0,563 1,128 1,693 2,258 2,821
9000 0 0,712 1,424 2,136 2,848 3,561
10000 0 0,867 1,734 2,604 3,472 4,341
11000 0 1,043 2,086 3,130 4,173 5,217
12000 0 1,265 2,530 3,795 5,060 6,325
13000 0 1,484 2,968 4,454 5,939 7,426
14000 0 1,724 3,448 5,172 6,897 8,621
15000 0 1,978 3,957 5,936 7,915 9,894
16000 0 2,250 4,502 6,752 9,004 11,254
17000 0 2,541 5,083 7,625 10,167 12,709
18000 0 2,850 5,700 8,551 11,401 14,251
19000 0 3,173 6,348 9,524 12,699 15,872
20000 0 3,516 7,035 10,554 14,073 17,592

Tab. 2. Valorile lui [DELTA]F (x[10.sup.-2] N) pentru inel
[empty set]48 si cursor 11/0

 e (mm)
[n.sub.f]
(rpm) 0 0,2 0,4 0,6 0,8 1,0

6000 0 0,338 0,679 1,017 1,359 1,699
7000 0 0,457 0,918 1,376 1,836 2,294
8000 0 0,601 1,205 1,809 2,413 3,015
9000 0 0,761 1,522 2,188 3,044 3,805
10000 0 0,926 1,853 2,783 3,710 4,639
11000 0 1,115 2,230 3,345 4,460 5,575
12000 0 1,351 2,703 4,055 5,407 6,75o
13000 0 1,586 3,172 4,761 6,347 7,935
14000 0 1,842 3,685 5,528 7,370 9,212
15000 0 2,114 4,229 6,345 8,458 10,573
16000 0 2,404 4,811 7,216 9,622 12,026
17000 0 2,716 5,432 8,150 10,865 13,581
18000 0 3,045 6,091 9,139 12,183 15,229
19000 0 3,390 6,784 10,179 13,570 16,961
20000 0 3,758 7,518 11,280 15,039 18,799

Tab. 3. Valorile lui [DELTA]F (x[10.sup.-2] N) pentru inel
[empty set]48 si cursor 6/0

 e (mm)
[n.sub.f]
(rpm) 0 0,2 0,4 0,6 0,8 1,0

6000 0 0,533 1,068 1,600 2,137 2,670
7000 0 0,721 1,442 2,165 2,887 3,609
8000 0 0,946 1,396 2,845 3,794 4,743
9000 0 1,136 2,393 3,590 4,787 5,984
10000 0 1,457 2,915 4,376 5,834 7,294
11000 0 1,752 3,504 5,258 7,011 8,763
12000 0 2,123 4,250 6,276 8,502 10,626
13000 0 2,493 4,988 7,480 9,980 12,475
14000 0 2,896 5,794 8,692 11,588 14,486
15000 0 3,326 6,650 9,975 13,300 16,627
16000 0 3,783 7,564 11,347 15,130 18,913
17000 0 4,271 8,542 12,811 17,084 21,356
18000 0 4,787 9,577 14,367 19,157 23,946
19000 0 5,335 10,668 16,002 21,338 26,676
20000 0 5,912 11,823 17,736 23,648 29,561