A method for calculating the diameter of roving containing hollow fibers

Abstract

The present invention belongs to the technical field of spinning, and discloses a method for calculating the diameter of roving containing hollow fibers, which is applicable to the calculation of the diameter of roving in pure spinning of hollow fibers or in blended spinning of hollow fibers and non-hollow fibers. The hollow fiber sliver or blended sliver enters the roving frame through the feeding mechanism, and finally winds on the bobbin after being drafted by the rollers and twisted by the flyer. The diameter d of the roving on the bobbin is affected by the roving weight per unit length W, the roving twist T, and the proportion β of hollow fibers. The proportion β of hollow fibers refers to the proportion of hollow fibers in the fiber raw materials. The calculation formula for the diameter of the roving containing hollow fibers is:; where d is the diameter of the roving containing hollow fibers, is the regression equation related to the influence of the roving weight per unit length W, is the regression equation related to the influence of the roving twist T, and and are the regression equations related to the influence of the proportion β of hollow fibers. The t in and is 5 to 9 twists / 10 cm. The present invention takes into account the characteristics of hollow fibers and the influence of twisting, and is more in line with the actual diameter of the blended roving of hollow fibers.

Description

Technical Field

[0001] The invention belongs to the technical field of spinning and relates to a method for calculating the diameter of a roving containing hollow fibers. Background Art

[0002] The traditional roving winding model is derived based on the circular fiber cross section, taking into account the mutual extrusion between rovings to form an elliptical yarn layer, such as Figure 5 As shown, d is the short diameter of the ellipse, which is also the thickness of the yarn layer, that is, the roving diameter (cm), and h is the long diameter of the ellipse. As the number of yarn layers increases, the thickness of the yarn layer on the bobbin is also increasing. It is generally believed that the increase in yarn layer thickness is equal, that is, the yarn layer thickness of each layer of yarn is equal, and the yarn layer thickness of each layer of yarn is related to the roving diameter, so the basis of the traditional roving winding model is the derivation of the roving diameter. The derivation of the roving diameter law on the current roving machine is based on the longitudinal winding density Q (turns / 10cm) during roving winding, where the relationship between Q and d is:

[0003] ;

[0004] in is the roving density (g / cm 3 ), W is the roving weight (g / 10m), the change relationship is as follows Figure 6 shown.

[0005] It can be seen from the above formula that the traditionally derived roving diameter is closely related to the raw material correlation coefficient, but the influence of twisting during the roving winding process is not taken into account. For some raw materials such as cotton fibers with small hollowness and polyester fibers without hollowness, the internal structure of the slivers is closely arranged, and the force generated during the twisting process is not enough to squeeze the roving, so the twisting effect has little effect on the calculated roving diameter. For raw materials with relatively large hollowness, such as kapok fiber and ox-horn melon fiber, since the hollowness of the fiber is more than 80%, the slivers formed are also relatively fluffy, and their internal structure is also relatively loose, which is easily affected by force. In addition, there are problems such as poor forming and easy breakage during roving winding, so twisting is also required, and the force during the twisting process will also easily squeeze the roving, which further affects the calculation of its roving diameter.

[0006] For example, in the literature (Establishment and Application of the Mathematical Model for the Roving Winding Speed of Roving Machines [J]. Shanghai Textile Science & Technology, 2005, 33(3):3. DOI: 10.3969 / j.issn.1001 - 2044.2005.03.004.), the variation law of the traditional roving diameter was deduced (i.e., the above formula Q), and the applicability of this formula to fibers such as cotton, polyester, and acrylic was analyzed. However, the analysis of hollow fibers such as kapok and calotropis gigantea was not mentioned. Therefore, the specific law of the roving diameter of hollow fibers during the roving process still needs to be further explored.

[0007] Therefore, a method for calculating the roving diameter containing hollow fibers is needed to solve the above problems, which is of great significance. Summary of the Invention

[0008] The purpose of the present invention is to solve the problems existing in the prior art and provide a method for calculating the roving diameter containing hollow fibers.

[0009] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0010] A method for calculating the roving diameter containing hollow fibers is applicable to the calculation of the roving diameter during the pure spinning of hollow fibers or the blending of hollow fibers and non - hollow fibers. The hollow fiber sliver or blended sliver enters the roving machine through a feeding mechanism, undergoes roller drafting and spindle - wing twisting mechanisms, and is finally wound on a bobbin. The roving diameter d on the bobbin is affected by the roving weight per unit length W, the roving twist T, and the proportion β of hollow fibers. The proportion β of hollow fibers refers to the proportion of hollow fibers in the fiber raw material, with a value range of 0 - 1. The calculation formula for the roving diameter containing hollow fibers is:

[0011] ;

[0012] where d is the roving diameter containing hollow fibers, is the regression equation related to the influence of the roving weight per unit length W, is the regression equation related to the influence of the roving twist T, and is the regression equation related to the influence of the proportion β of hollow fibers, and the t in is 5 - 9 turns / 10 cm;

[0013] The regression equation is:

[0014] ;

[0015] where:

[0016] ;

[0017] ;

[0018] ;

[0019] Regression equation The selected coefficients are related to the value of t. For example, when t is fixed at 7 turns / 10 cm, its variation law is as Figure 1 shown.

[0020] Regression equation is:

[0021] ;

[0022] Regression equation is:

[0023] ;

[0024] is an influencing factor related to the roving count W, is an influencing factor related to the roving twist T. The regression equations and are respectively:

[0025] ;

[0026] .

[0027] The principle of calculating the diameter of the roving containing hollow fibers in the present invention is as follows: Since the roving count is the main factor affecting the diameter of the roving containing hollow fibers, considering the influence of the subsequent roving twist, in the case of selecting the roving twist of t turns / 10 cm, only change the roving count to conduct a certain amount of roving winding experiment, measure and calculate the roving diameter under different roving counts, and make a relationship graph between the roving count and the roving diameter. Through function fitting, establish the regression equation of the roving diameter and the roving count; then, through a series of experiments of only changing the roving twist and performing the same data calculation and processing, the regression equation of the roving diameter and the roving twist can be obtained. However, since the roving twist is a secondary influencing factor, when both the roving count and the roving twist change, the actual roving diameter is mainly affected by the roving count. Therefore, take and the value of the roving twist t (turns / 10 cm) selected in the regression equation in , that is to make a ratio, and take as the influence coefficient of the twist and consider it in the influence of the regression equation , thereby affecting the calculation of the roving diameter; since it is relatively difficult to spin pure hollow fibers, the regression equations and All are obtained from the hollow fibers and non-hollow fibers applicable to this method at a certain blending ratio. Therefore, the influencing factors of the blending ratio coefficient of the two are taken into account. and The average value of is used as another blending ratio coefficient and considered in the calculation of the roving diameter. In summary, the calculation formula for the roving diameter applicable to the roving containing hollow fibers, mainly considering the influencing factor of roving weight per unit length and also taking into account the two influencing factors of roving twist and blending ratio coefficient, can be obtained.

[0028] As a preferred technical solution:

[0029] In a method for calculating the roving diameter of roving containing hollow fibers as described above, the hollow fiber is kapok fiber or calotropis gigantea fiber, and the hollowness of the hollow fiber is 80-90%.

[0030] In a method for calculating the roving diameter of roving containing hollow fibers as described above, the non-hollow fiber is cotton fiber, silk or chemical fiber.

[0031] In a method for calculating the roving diameter of roving containing hollow fibers as described above, the roving weight per unit length W is 2-18 g / 10 m.

[0032] In a method for calculating the roving diameter of roving containing hollow fibers as described above, the roving twist T is 3-10 turns / 10 cm.

[0033] Beneficial effects:

[0034] Compared with the prior art, by considering the twisting effect during the roving winding process, the present invention takes the twisting factor into account in the calculation of the roving diameter, so that the calculation of the roving diameter of the roving containing hollow fibers can be realized. The roving diameter calculated by this method can reach 95%-103% of the actual roving diameter of the hollow fiber, and the calculation result is closer to the diameter of the pure-spun or blended roving of the hollow fiber than the traditional calculation method. Description of the drawings

[0035] Figure 1 It is a curve graph showing the change relationship of the regression equation related to the roving weight per unit length and the roving diameter in the present invention; ;

[0036] Figure 2 It is a curve graph showing the change relationship of the regression equation related to the roving twist and the roving diameter in the present invention; ;

[0037] Figure 3 It is a curve graph showing the change of the influencing factor of the blending ratio in the roving weight per unit length in the present invention; ;

[0038] Figure 4 It is the influencing factor of the blending ratio in the roving twist in the present invention. Variation curve graph;

[0039] Figure 5 It is a cross-sectional view of an elliptical yarn layer; in the figure, d is the roving diameter (unit: cm), and h is the major axis of the ellipse (unit: cm);

[0040] Figure 6 Under the traditional method of calculating the roving diameter, the fixed roving density is 0.3 g / cm 3 When, the variation curve graph of the roving diameter and the roving count. Specific embodiments

[0041] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0042] To ensure the full disclosure of the performance of the substances used in each example and comparative example, the manufacturers and grades of the substances are stated. Products of other manufacturers and grades that meet the limitations of the present invention are also feasible.

[0043] A method for calculating the roving diameter containing hollow fibers, which is applicable to the calculation of the roving diameter when hollow fibers are spun alone or when hollow fibers are blended with non-hollow fibers. The specific process is as follows:

[0044] First, the hollow fiber raw material or the raw material after mixing hollow fibers and non-hollow fibers is formed into a uniform hollow fiber sliver or blended sliver through carding and drawing processes, and then enters the roving frame through the feeding mechanism, and is finally wound on the bobbin through the roller drafting and flyer twisting mechanisms;

[0045] The roving diameter d on the bobbin is affected by the roving count W, the roving twist T, and the proportion β of hollow fibers. The proportion β of hollow fibers refers to the proportion of hollow fibers in the fiber raw material, and the value range is 0 to 1. The calculation formula for the roving diameter containing hollow fibers is:

[0046] ;

[0047] Among them, d is the roving diameter containing hollow fibers, is the regression equation related to the influence of the roving count W (the relationship changes as Figure 1 shown), is the regression equation related to the influence of the roving twist T (the relationship changes as Figure 2 shown), and The regression equation related to the influence of the proportion β of hollow fibers (the relationship changes as shown in Figure 3 , Figure 4 ), and the t in it is 5 - 9 turns / 10 cm;

[0048] The roving count W is 2 - 18 g / 10 m, and the calculation formula of the regression equation is:

[0049] ;

[0050] Among them:

[0051] ;

[0052] ;

[0053] ;

[0054] When t is fixed at 7 turns / 10 cm, the change rule of the roving diameter d with the roving count W is as shown in Figure 1 ;

[0055] The roving twist T is 3 - 10 turns / 10 cm, and the change rule of the roving diameter d with the roving twist T is as shown in Figure 2 , and the calculation formula of the regression equation is:

[0056] ;

[0057] The calculation formula of the regression equation is:

[0058] ;

[0059] and The change rules with the proportion β of hollow fibers are respectively as shown in Figure 3 , Figure 4 , and the calculation formulas of the regression equations and are respectively:

[0060] ;

[0061] .

[0062] When calculating the roving diameter d on the bobbin by the traditional method, the longitudinal winding density Q (turns / 10 cm) during roving winding is calculated according to the following formula, and then the roving diameter d is obtained;

[0063] ;

[0064] Under the traditional method of calculating the roving diameter, when the roving density is fixed at 0.3 g / cm 3 , the variation law of the roving diameter d with the roving weight per unit length W is as Figure 5 shown.

[0065] Example 1

[0066] A method for calculating the roving diameter containing hollow fibers, the specific process is as follows:

[0067] (1) Combing kapok fibers with an average hollowness of 83% and non-hollow cotton fibers and then forming a uniform blended sliver through the drawing process; among them, the proportion of kapok fibers in the fiber raw materials is 0.3;

[0068] (2) Feeding the blended sliver into a roving frame through a feeding mechanism, and finally winding it on a bobbin through a roller drafting and flyer twisting mechanism; among them, the roving weight per unit length W is 7 g / 10 m, the roving twist T is 7 turns / 10 cm, and the roving density is 0.3 g / cm 3 ;

[0069] = 0.0441;

[0070] t is 7 turns / 10 cm, = 0.0441;

[0071] = 0.0430;

[0072] = 0.9732, = 0.9757.

[0073] First, use a vernier caliper to measure and calculate the actual roving diameter after unwinding through data fitting to be 0.0412 cm, and then calculate the value of the roving diameter d on the bobbin respectively using the above calculation formula of the present invention and the traditional calculation formula of the prior art. The results are as follows:

[0074] Using the above calculation formula of the present invention, the value of the roving diameter d on the above bobbin is calculated to be 0.0419 cm;

[0075] Using the traditional method calculation formula, the value of the roving diameter d on the above bobbin is calculated to be 0.0386 cm;

[0076] By comparing the values of the roving diameter d calculated by the above two methods with the actually measured values, it can be seen that compared with the traditional calculation method, the roving diameter d obtained by the calculation formula used in the present invention is closer to the actual roving diameter, fully considering the characteristics of hollow fibers and the influence of twisting, and is more in line with the diameter change law of hollow fiber blended rovings.

[0077] Example 2

[0078] A method for calculating the diameter of a roving containing hollow fibers is as follows:

[0079] (1) Fibers of Calotropis gigantea with an average hollowness of 85% and non-hollow cotton fibers are formed into a uniform blended sliver after carding and drawing processes; among them, the proportion of Calotropis gigantea fibers in the fiber raw materials is 0.6.

[0080] (2) The blended sliver enters the roving frame through the feeding mechanism, and is finally wound on the bobbin after roller drafting and flyer twisting mechanisms; among them, the roving weight per unit length W is 5 g / 10 m, the roving twist T is 7 turns / 10 cm, and the roving density is 0.3 g / cm 3 ;

[0081] = 0.0441;

[0082] t is 6 turns / 10 cm, = 0.0472;

[0083] = 0.0418;

[0084] = 1.1325, = 1.1155.

[0085] First, use a vernier caliper to measure and calculate the actual roving diameter after unwinding by data fitting, which is 0.0445 cm. Then, calculate the value of the roving diameter d on the bobbin using the above calculation formula of the present invention and the traditional calculation formula of the prior art respectively. The results are as follows:

[0086] Using the above calculation formula of the present invention, the value of the roving diameter d on the bobbin is calculated to be 0.0439 cm;

[0087] Using the traditional method calculation formula, the value of the roving diameter d on the bobbin is calculated to be 0.0326 cm;

[0088] By comparing the values of the roving diameter d calculated by the above two methods and the actually measured values, it can be seen that, compared with the traditional calculation method, the roving diameter d obtained by the calculation formula used in the present invention is closer to the actual roving diameter, fully considering the characteristics of hollow fibers and the influence of twisting, and more conforming to the diameter change law of hollow fiber blended rovings.

[0089] Example 3

[0090] A method for calculating the diameter of a roving containing hollow fibers is as follows:

[0091] (1) Kapok fibers with an average hollowness of 83% and non-hollow polyester fibers are formed into a uniform blended sliver through carding and drawing processes; among them, the proportion of kapok fibers in the fiber raw materials is 0.4.

[0092] (2) The blended sliver enters the roving frame through the feeding mechanism, and is finally wound on the bobbin through the roller drafting and flyer twisting mechanisms; among them, the roving weight per unit length W is 8 g / 10 m, the roving twist T is 7 turns / 10 cm, and the roving density is 0.3 g / cm 3 ;

[0093] = 0.0441;

[0094] t is 8 turns / 10 cm, = 0.0418;

[0095] = 0.0432;

[0096] = 1.0263, = 1.0223.

[0097] First, use a vernier caliper to measure and calculate the actual roving diameter after unwinding through data fitting to be 0.0459 cm. Then, calculate the value of the roving diameter d on the bobbin by using the above calculation formula of the present invention and the traditional calculation formula of the prior art respectively. The results are as follows:

[0098] Using the above calculation formula of the present invention, the value of the roving diameter d on the above bobbin is calculated to be 0.0467 cm;

[0099] Using the traditional method calculation formula, the value of the roving diameter d on the above bobbin is calculated to be 0.0412 cm;

[0100] By comparing the values of the roving diameter d calculated by the above two methods with the actually measured values, it can be seen that compared with the traditional calculation method, the roving diameter d obtained by the calculation formula used in the present invention is closer to the actual roving diameter, fully considering the characteristics of hollow fibers and the influence of twisting, and more conforms to the diameter change law of hollow fiber blended rovings.

[0101] Example 4

[0102] A method for calculating the diameter of a roving containing hollow fibers is as follows:

[0103] (1) Combed kapok fibers with an average hollowness of 83% are formed into uniform sliver after carding and drawing processes;

[0104] (2) The kapok sliver enters the roving frame through the feeding mechanism, and is finally wound on the bobbin after roller drafting and flyer twisting mechanisms; among them, the roving weight per unit length W is 6 g / 10 m, the roving twist T is 7 turns / 10 cm, and the roving density is 0.3 g / cm 3 ;

[0105] = 0.0441;

[0106] t is 7 turns / 10 cm, = 0.0441;

[0107] = 0.0408;

[0108] = 1.3449, = 1.3019.

[0109] First, use a vernier caliper to measure and calculate the actual roving diameter after unwinding by data fitting, which is 0.0552 cm. Then, calculate the value of the roving diameter d on the bobbin using the above calculation formula of the present invention and the traditional calculation formula of the prior art respectively. The results are as follows:

[0110] The value of the roving diameter d on the above bobbin calculated by using the above calculation formula of the present invention is 0.0540 cm;

[0111] The value of the roving diameter d on the above bobbin calculated by using the traditional method calculation formula is 0.0356 cm;

[0112] By comparing the values of the roving diameter d calculated by the above two methods with the actually measured values, it can be seen that compared with the traditional calculation method, the roving diameter d obtained by the calculation formula used in the present invention is closer to the actual roving diameter, fully considering the characteristics of hollow fibers and the influence of twisting, and more conforms to the diameter change law of rovings containing hollow fibers.

Claims

1. A method for calculating the diameter of roving containing hollow fibers, which is suitable for calculating the diameter of roving when hollow fibers are spun alone or when hollow fibers are blended with non-hollow fibers. Hollow fiber slivers or blended slivers enter the roving frame through a feeding mechanism, and are finally wound on a bobbin after being drawn by rollers and twisted by a winglet. The method is characterized in that: The diameter d of the roving on the bobbin is affected by the roving weight W, the roving twist T and the hollow fiber ratio β. The hollow fiber ratio β refers to the proportion of hollow fibers in the fiber raw material, and the value range is 0 to 1. The calculation formula of the roving diameter is: Wherein, d is the diameter of the roving containing hollow fibers, Y1(W, t) is the regression equation related to the influence of the roving quantity W, Y2(T) is the regression equation related to the influence of the roving twist T, β1 and β2 are the regression equations related to the influence of the hollow fiber proportion β, and the selected roving twist t in Y1(W, t) and Y2(t) is 5 to 9 twists / 10cm; The regression equation Y1(W,t) is: Y1(W,t)=exp(A(t)+B(t)W+C(t)W 2 ); in: A(t)=-2.70901-0.06788t; B(t)=-0.06796-0.0028t; C(t) = 0.00934-0.00024t; The regression equation Y2(T) is: Y2(T)=exp(-2.32718-0.16677T+0.0076T 2 ); The regression equation Y2(t) is: Y2(t)=exp(-2.32718-0.16677t+0.0076t 2 ); β1 is the influencing factor related to the roving weight W, β2 is the influencing factor related to the roving twist T, and the regression equation is β1 and β2 are: β1＝0.531β+0.8139； β2＝0.466β+0.8359。 2. A method for calculating the diameter of a roving containing hollow fibers according to claim 1, characterized in that: The hollow fiber is kapok fiber or kiwano fiber, and the hollowness of the hollow fiber is 80-90%.

3. A method for calculating the diameter of a roving containing hollow fibers according to claim 2, characterized in that: The non-hollow fibers are cotton fibers, silk or chemical fibers.

4. A method for calculating the diameter of a roving containing hollow fibers according to claim 1, characterized in that: The roving weight W is 2 to 18 g / 10 m.

5. A method for calculating the diameter of a roving containing hollow fibers according to claim 1, characterized in that: The twist T of the roving is 3 to 10 twists / 10cm.

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