1、4 SEPTEMBER 1963 MILITARY SPECIFICATION CLOTH, SPUN VISCOSE RAYON, RESIN IMPREGNATED 1. SCOPE STANDARDS 1.1 Scope. This specification covers three classes of cloth designated as Cloth, Spun Viscose Rayon, Resin Impregnated, for use with ammunition. 1.2 Clas Test Methods PPP-B-601-Boxes, Wood, Cleate
2、d Ply- wood DDD-S-751-Stitches, Seams and Stitching PPP-B-585-Boxes, Wood Wirebound (Overseas Type) PPP-B-62l-Boxes, Wood, Nailed and Locker Corner two A owmeters in- dicate the flow. The excess mixture from the first mixing bulb passes through two towers packed with pellets or flasks of solid sodiu
3、m hydroxide to remove the dinitrogen tetroxide, and on out the aspirator. The gas from the second mixing bulb, which consists of air whose temperature is determined by the tem- perature of the room or enclosure in which lPrcduets of Eastman Chemical Products, Inc., Kingsport, Tennessee. Licensed by
4、Information Handling ServicesMIL-C-Y3157 83 W 777790b 0372287 8 W MIGC-43 157 (MU) the equipment is placed, and which has the desired dinitrogen tetroxide content, and rel- ative humidity, flows over the specimens suspended in the exposure chamber. It then passes through the sodium hydroxide towers,
5、 and on to the aspirator. The pressure in the system is governed by the adjustment of the aspirator, and by the head of the ethylene glycol above the lower end of the open tube in the regulator in the lower right of the diagram. The exposure chamber is a 13-liter pyrex jar equipped with a ground gla
6、ss cover. The specimens are supported by a stainless steel rack which is rotated at a rate of ap- proximately 1 revolution per minute by a gear train and motor mounted on the cover. A wooden support holds the cover, and at- tached specimen rack when not in position on the exposure chamber. A plain g
7、lass cover is used to close the chamber when sweeping out the exposure train with air before, and after exposures. The two sampling parts shown in figure 1 provide for the removal of samples of air for chemical analysis from the exposure chamber, and from the stream of air entering the chamber. The
8、humidifier consists of a plexiglass box 2 inches deep, 9 inches wide, and 12 inches long, filled to a depth of approximately I inch with a satu- rated salt solution. The box is equipped with baffles so that the air passing through it flows over a layer of sdution one inch wide, and 9 feet long. A st
9、oppered opening in the top of the box near the outlet provides for the insertion of a sensitive element of an electric hygrometer, if desired. The four flowmeters are of the ball-float type and, as shown in the diagram from left to right, have maixmum capacities of 42, 410, 116 and 960 milliliters p
10、er minute of air 70 degrees Fahrenheit at one atmosphere. The float of the meter used to measure dry air is of stainless steel; those of the other three meters are of the sapphire. (a) Tensile testing machine. The ten- sile testing machine shall be as specified in Specification CCC-T- 191, Method 51
11、00. (b) Apparatus for conditioning. Pro- visions for conditioning the spec- imens, and measuring their 6 breaking strengths in air at specified temperature and rela- tive humidity shall be in accord- ance with specification CCC-T- 191, Textile Test Methods, Part 1, Section 4-Atmospheric Con- ditions
12、 for Testing. (e) Cylinder of dinitrogen tetroxide (98 percent pure), (d) Saturated magnesium nitrate solu- tion for humidifier. (e) Sodium hydroxide flakes or pellets for neutralizer. (f) Ethylene glycol for pressure regu- latox. (g) Magnesium perchlorate and indi- cating Drierite for drying tower.
13、 4.3.3.1 Preparation of specimen. The speci- .mens shall be prepared from each sample as lfollows: Cut two strips of cloth 28 inches )long and 142 inches wide at random from the fabric parallel to the wrap yarns. Cut two similar strips parallel to the filling yarns. Ravel each strip to a width of on
14、e inch by taking approximately the same number of yarns from each side. Mark the strips into four 7-inch specimens, labeling each speci- men for identification. Cut the two end speci- mens from each strip and retain for controls, . The 14 inch strips are to be used for exposure to dinitrogen tetroxi
15、de and are not to be cut into 7 inch strips until after exposure. 4.3.3.2 Procedure. The specimens (see 4.3.3.1) shall be tested as follows : Condition specimens at 21C. and 65 percent relative humidity for at least 48 hours prior to ex- posure. Only two 14 inch strips (1 warp and 1 filling) of any
16、one fabric are to be exposed to dinitrogen tetroxide at the same time. Strips of different fabrics may be exposed to- gether (see 6.4). With the plain cover on the exposure chamber, and the needle valve be- tween the dinitrogen tetroxide cylinder and flowmeter 1, shown on the left in figure 1, shown
17、 on the left in figure 1, closed, turn on the aspirator. Adjust the needle valves at flowmeters 2, 3 and 4 to give a stream of air having a relative humidity of 45 f 3 per- cent. at 27 -t- 2OC., and rate of flow . .i I .c ._ , L :, i Licensed by Information Handling Servicessufficient to change the
18、atmosphere in the chamber four times an hour. Suspend the strips of fabric from one end of the specimen rack. After the aspirator has been running thirty minutes, replace the plain cover on the exposure chamber with the ground glass cover with attached rack, and strips of fabric. Start the specimen
19、rack rotating. One hour after the introduction of the specimens into the exposure chamber, open the needle valve on flowmeter 1 halfway. Slowly open the outlet valve on the dinitrogen tetroxide cylinder until the reading on floiv- meter 1 is approximately that required to give concentration of 0.2 p
20、ercent dinitrogen tetroxide by volume to the stream of air en- tering the exposure chamber. Make the fine adjustment at flowmeter 1 with the needle valve. Make any necessary adjustments of the needle valves at flowmeters 2, 3 and 4 to maintain the relative humidity, and rate of flow. At the end of 2
21、 hours from the time the flow of dinitrogen tetroxide was started, close the outlet valve on the cylinder, open the stopcocks on the two sampling parts, and remove the cover, and attached 14 inch strips. Immediately cover the exposure chamber with the plain glass cover, close the sampling ports, and
22、 continue to draw air through the apparatus for at least an hour to sweep the dinitrogen tetroxide from the mixing and ex- posure chambers, and attached tubes. Cut the 14 inch strips into 7-inch specimens. Con- dition the exposed specimens, and the cor- responding control specimens by exposure os 20
23、 hours to air at 21C. and relative humidity at 65 percent. Determine the breaking strength of the exposed and control specimens as specified in Specification CCC- T-191, Method 5100. Calculate the strength loss for each of the exposed specimens from the following formula : Percent breaking strength
24、loss = 100 (EX100) u where : E = breaking strength of exposed speci- men. U = breaking strength of control speci- men that was adjacent to the ex- posed specimen in the original 28-inch strip of fabric. Repeat the above procedure until all speci- mens of the fabric have been tested. 4.3.4 Slippage u
25、alue-Code No. 12001. 4.3.4.1 Appayatus. For the determina- tion of slippage value, a pendulum type test- ing machine shall be used as specified in Specification CCC-T-191, Method 5100. 4.3.4.2 Prepcwaton of specimens. Speci- mens, 4 inches wide and 16.0 to 16.5 inches long, shall be taken for test.
26、Two sets of five specimens each are required, one set for warp slippage value, having the short dimen- sion parallel to the warp yarns, and the other set for the filling slippage value having the short dimension parallel to the filling yarns. No two specimens for warp slippage shall contain the same
27、 warp yarns and no two specimens for filling slippage shall contain the same filling yarns. Unless otherwise spec- ified, no specimen shall be taken nearer the salvage than one-tenth the width of the ma- terial, The specimens shall be prepared by cutting strips of cloth of the number in the directio
28、ns specified above, approximately 4.5 inches wide and 17 inches long. Any cut or broken threads shall be then raveled from the strip of cloth until only threads remain in the lengthwise direction of the cloth which are approximately the same length as the cloth strip and only threads remain in the s
29、hort direction which are approximately as long as the width of the cloth strip. Sufficient yarns shall be raveled from both the long and short dimensions of the strip of cloth until the specimen is 4 inches wide by 16 to 16.5 inches long. Any other convenient method of preparing the specimen may be
30、used provid- ed it does not affect the physical properties of the cloth. A test specimen shall be folded back on itself so that the distance from the fold to one edge, parallel to the short dimen- sion, measures approximately 5 inches and to the opposite edge at least 10 inches, The fold must be par
31、allel to the crosswise yarns in the specimen. At 0.38 inch from the fold, a seam shall be sewn parallel to the crosswise yarns of the specimen. The seam shall be of Licensed by Information Handling ServicesMIL-C-Y3357 83 W 9999906 0392293 b MIGG43157 (MU) the type designated as 301-SSa-1 by Speci- f
32、ication DDD-S-751. (The seam SSa-1 shall be made with 1 row of stitch, 12 stitches per inch, Type 301.). The seam shall be made with a suitable needle and a thread of suffi- cient strength so that it will not break when the seam is tested for elongation as directed below, The specimens shall be cond
33、itioned for at least 24 hours at 21 rt: 2 C. and 65 3- 2 percent relative humidity. 4.3.4.3 Procedure. The distance between the jaws of the test machine shall be adjusted to 3 inches. A 6 ounce clamp shall at attached to the 10 inch length of the specimen, parallel to, end at a distance of 3 inches
34、from the seam described in 4.3.4.2. The clamp can be assembled from a metallic photographic film clip approximately 5 inches long, a brass or steel rod 6 inches long and 3/16 inch in di- ameter or brass or steel weights, equal in weight, attached to the 6 inch rod to bring the total weight of the as
35、sembly to 6 ounces. The test specimen shall be placed with the 10 inch portion uppermost, symmetrically in the up- per jaws of the test machine so that the long direction of the specimen is parallel to the direction of the application of the load. The specimen shall be clamped in the upper jaws so t
36、hat the 6 ounce clamp described above is approximately inch below the lower jaws of the test machine. The test machine shall be reset so that a zero load is shown on the graphic record. The 6 ounce clamp shall be checked to be certain that it is supported on- ly by the test specimen and that a unifo
37、rm tension of 6 ounces is applied to the specimen. The lower jaws of the test machine shall be fastened to specimen, care being taken that the same yarns gripped in the lower jaws are gripped in the upper jaws. The apparatus shall be arranged to obtain a tension-stretch curve up to the breaking stre
38、ngth of the spec- imen, and stretch being indicated in inches by the vertical component of the curve and the tension being indicated in pounds by the horizontal component. The machine shall be started and allowed to apply tension until the specimen breaks. This graphic record shall be designated as
39、the fabric-strength curve. The same specimen shall be inserted in the jaws of the machine so that the seam is in a position parallel to the jaws and midway between the upper and lower jaws. The spec- imen shall be clamped in the jaws, with tension being applied by means of the 6 ounce clamp, as dire
40、cted above, before tightening the lower jaws, The apparatus shall be arranged so that a graphic record of this test will be made on the same chart and will start at the same point as the fabric- stretch curve, The machine shall be started and allowed to apply tension to the specimen until either the
41、 cloth breaks or the seam fails, This graphic record shall be designated as the seam-stretch curve. The tension shall be noted at which the vertical distance be- tween the seam-stretch curve and the fabric- stretch curve is equal to the sum of: a. the vertical distance between these curves when the
42、tension is 1 pound, and b. a vertical distance on the chart equiv- alent to 0.25 inch on the cloth. The slippage shall be calculated as follows : 100 A Slippage value = 25 where : A = tension at which the difference be- tween the seam-stretch curve and the fabric- stretch curve is 0.25 inch plus the
43、 difference between these curves when the tension is 1 pound, The slippage value in the warp direc- tion shall be considered as the average of five results obtained for the warp slippage specimens and the slippage value in the fill- ing direction as the average of five results obtained for the filli
44、ng slippage specimens. 4.3.5 Stretch-Coda No. 13001. The per- cent strength shall be determined concurrent- ly with the slippage value and shall be calculated as shown below from measure- ments of the fabric-stretch curve of the graphic record, The percent of stretch of the warp yarns is obtained wh
45、en the slippage value of the filling yarns is determined. The percent of stretch of the filling yarns is ob- tained from the fabric-stretch curve when slippage value of the warp yarn is deter- mined, The percent of stretch in each direc- tion shall be considered as the average of Licensed by Informa
46、tion Handling ServicesLicensed by Information Handling Services- - -.II_- I MIL-C-LI3L57 83 m 7777706 0372273 T m MLG43157(MU) (a) Title, number and date of this spec- (b) Class of cloth required. (c) Width of material required. (see 3.3) (d) Color of material required. (see 3.12). (e) Levels of pro
47、tection. (see 6.1). ification. 6.3 Finish. One finish that has been found satisfactory is the Permel Plus finish - American Cyanamid Co, This finish deposits on the desized cloth, dry basis, 12 to 14 per- cent solids urea formaldehyde resin (Aerotex cream 460) and 6-8 percent solids melamine resin b
48、ase (Permel B) , 6.3.1, Processing. The processing condi- tions that give the above finish are as fol- lows : Aerotex Cream 450 20 Permel Resin B 15 Aerotex Resin 159 6 Aerotex Buffer DCY 0.54 Aeyotex Accelerator 1.00 Impregnating Bath Cmposition Percent Impregnation : Immersion: 2 dips 2 nips Press
49、ure: 2.9 tons Expression: 100 percent Dry at 226F. Cure at 300F. for 3 to 4 minutes. 6.4 Breaking strength loss. Crowding of the exposure chamber has been found to give Dry and Cure: Custodian : ARMY-MU 10 poor reproducibility and high values for di- nitrogen tetroxide resistance. It is recom- mended, therefore, that no more than 6 different fabrics be exposed together and that one of these be a cotton fabric whose dini- trogen tetroxide resistance has been de- termined previously, Failure of the value obtained for the dinitrogen tetroxide resist- ance of this fabric to agree
