1、MIL-HDBK-741 3 I 7777970 0053775 5 I fl-yL-/,. Yarn Bulk Densities of Blends of the Important Comercial Fibersa,.,.,. Maximum Value of Filling Cover Factor K2 in Terms of Warp Cover Factor, Beta Factor, and Yarn Bulk T)ensity.,., (A) Plain Weave Fabcs,.,., (B) Three-harness Weave Fabrics.4 (C) Four-
2、harness Weave Fabrics . (D) Five-harness Weave Fabrics*b. (E) Oxford Fabrics., . Page 29 33 45 47 103 155 211 . 2 75 LIST OF ILLUSTRATIONS Fig. NO. Title Page A-l A-2 A-3 A-4 . 16 1 Construction for Filling Yarn Spacing Construction for Filling Yarn Displacement Warp Yarn Arrangement in Twill Weaves
3、 Warp Yarn Arrangement in Twill Weaves 17 . (No (=Oression) 20 (Compressed Situation) 21 A-5 Yarn Compression Between the Float., 22 . - -1 - -=-. iv . Provided by IHS Not for Resale No reproduction or networking permitted without license from IHS -,-,-z. L 1 . MIL-HDBK-741 3 3797370 0051800 5 MIL-H
4、DBK-741 (GL) FABRIC DESIGN TABLES OF SOLUTIONS OF EQUATIONS FOR MAXIMUM WEAVABILITY FABRICS MADE FROM SINGLE FIBER SPECIES AND BLENDS 1-1 PURPOSE AND SCOPE 1-1.1 PURPOSE The tables in this handbook are presented to facilitate the designing of high-texture or maximum-weavable fabrics. Maximum- weavab
5、le fabrics are the largest class of functional fabrics used by industry and the military. Among many weaves they include ducks, poplins, wind-resistant twills and sateens, airplane and bailoon cloths, and. iinings. In designing maximum-weavable fabrics it is always of concern to the designer to know
6、 whether his fabric is practical in terms of the capacity of the loom to put in the necessary picks. The purpose of these tables is to eliminate the need for direct computation or for graphi- cal techniques previously used for obtaining the solution of maximum weavability prob- lems. For the fiist t
7、ime, the tables provide the solutions to the maximum weavability equa- tions for fabrics made from any type of fiber or from blends. These tables augment those published in Ref. 1* which can be used only for cotton fabrics. 1-1.2 SCOPE This handbook contains in tabular form the solution of the equat
8、ions for maximum weav- ability fabrics for the plain, Oxford, 3- and of 0.59 we get as the yarn bulk den sit y 1.14 x 0.59 = 0.67 The yarn bulk density table was prepared Ui this iiiantier. Thus, the first step to take in designing a niaxuiiuiii weavabie fabric-frotii say, Acrilaii-in the absence of
9、 experiiiientral data on yarn bulk densify, would be to rcfer to Table 1-1 for its bulk density. : Y I 2 t P Provided by IHS Not for Resale No reproduction or networking permitted without license from IHS -,-,-I t I r. . t MIL-HDBK-7qL 83 m 7777770 005L802 7 W MIL-HDBK-741 (GL) 1-3.2 YARN BULK DENSI
10、TY TABLE FOR BLENDS (TABLE 1-2) Table 1-2 provides, for blends of the most common fibers, the same information con- tained in Table 1-1 for single fiber yarns. Blend proportions are from 0% to 100% in 5% increments. The values in Table 1-2 were obtained from the solution of Eq. 1-2. 0.59 (Yarn bulk
11、A (! -A) densityof Dey = , +- na blendsfor whereDey = Defi = Der2 = A= ”V2 computing Table 1-2) bulk density of the blended Yarn fiber density of fiber #i fiber density of fiber #2 percentage of blended fiber #1 expressed as a decimal In Table 1-2 the fiber denslty of one of the component fibers is
12、given at the head of the first column with the percentage of that fiber (from 0% to 100%) given below it. The headings of the following eight columns give the fiber densities of the other component fibers, and the values in the body of the table are yarn bulk densities. For the problem solved by Eq.
13、 1-2 turn to the 0.59 section of Table 1-2 showing fiber density of 1.14 (for nylon) in first column: drop down to 25 (the percentage of nylon in blend) in first column, go across this row (25) to value under column headed 1.54 (fiber density of cotton): this will give bulk density of 0.84. If neces
14、sary, linear interpolation may be used for other blend percentages or fiber densities. 1-3.3 MAXIMUM WEVABILITY TABLE (TABLE 1-3) Table 1-3, “Maximum Value of Fiing Cover Factor K2 in Terms of Warp Cover Factor, Beta Factor, and Yarn Buk Density”, shows the maximum filling cover factor K2 that is th
15、eoretically obtainable for a given combination of warp cover factor and Beta A sample calculation for a blend of 25% nylon and 75% cotton is factor. The filling coier factors for the various yarn bulk densities and weaves were obtained by the solutions of Eqs. 1-3, the derivation of 0.59 Dc = = 0.84
16、 y - 0.25 + (1 -0.25) 1.14 1.54 which is given in Appendix A. I I Equations solved in setting up Table 1-3 I PLAIN WEAVE, M = 1 (1-3) THREE-HARNESS WEAVES, M = 1.5 3 Provided by IHS Not for Resale No reproduction or networking permitted without license from IHS -,-,-MIL-HDBK-741 (GL) I FOUR-HARNESS
17、WEAVES, M= 2.0 “*y%l)+l.ly + J-J75)+1.12LiJ = ,/(1-3) b.- 1.12 (1 +Pl 1.12 (i +P) FIVE-HARNESS WEAVES, M= 2.5 I 11- - 4 1.15 (1 +o) 1- 1.1s (1 +) OXFORD WEAVE, n-1, = 2.0,.M2 = 1.0 =1 1.12 (1 +) nuiiiber of yarns per repeat of weavc number of iiiterlacings per repeat of weave wlicrc Al = where 0 = B
18、eta factor or yarn balance I Cover factors* or Beta factor iiiay bc coiii- puted froiii Eqs. 1-4, 1-5, or 1-6. N, = warp yarn number N2 = iing yam nuniber (Warp cover factor =III a equafioii) (1-3) wherc KI = warp cover factor ri1 = warp texture or yarns per in. N, = warp yarn nuiiiber or “count” ri
19、2 (Filling cover factor (1-5) texture 2. Ref, 1 (Table 1-1)* Bcta Factor 0 1. Equation 1-6 (m;) w yarn niini- or ber and I yarn number 2, Ref. 1 (Table 1-2)* *Rcf. I providcs thc solution of thc covcr hcior equations (liqs. 14 und 1-5) and hc BCP fdctor cquafion Wq. 16) for a widc rangc of yarn nurn
20、bcrs and txturcs. The textile designer nomially has access to the information in the far right column above; this ciiables hini to make the preliminary calculations or to check in Tables 1-1 and 1.-2 to obtain the yarn bulk density to enter Table 1-3. Thus, if he is looking for the greatest number o
21、f filling yarns of a given size which can be used for a given weave type, he will know: (1) the fiber density or blend composition wliicli will then give him the yurn hulk derzsity De (2) tlie warp yarn number N, and.warp texture ti, whicli will provide tlie warp cover ajuctor KI (3) the filling yarn number N, that, with the warp yarn number NI, will provide the Bctu fuctor. 5 Provided by IHS Not for Resale No reproduction or networking permitted without license from IHS -,-,-
