1、26 March 1979 SUPERSEDING MIL-R-87120 (USAF) 7 April 1978 MILITARY SPECIFICATION RODS, PULTRUDED, GRAPHITE FIBER REINFORCED, PROCESSING OF This specification is approved for use by the Air Force Materials Laboratory, Department of the Air Force, and is available for use by all Departments and Agenci
2、es of the Department of Defense. 1. SCOPE 1.1 Scope. This specification establishes the processing require- ments and quality assurance provisions for pultruded rods. 2. APPLICABLE DOCUMENTS 2.1 Issues of documents. effect on date of invitation for bids or request for proposal, form a part of this s
3、pecification to the extent specified herein. The following documents of the issue in SPECIFICATIONS MILITARY MIL-C-4 5 6 6 2 Calibration Systems Requirements . M IL-Y - 8 7 1 2 5 Yarn, Graphite, 1000/3000 Filaments (Copies of specifications, required by contractors in connection with specific procur
4、ement functions should be obtained from the procuring activity or as directed by the contracting officer.) 2.2 Other publications, specification to the extent specified herein. indicated, the issue in effect on date of invitation for bids or request for proposal shall apply. The following documents
5、form a part of this Unless otherwise Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to the Air Force Materials Laboratory, MXA, WPAFB, Ohio 45433 by using the self-addressed Standardization Documen
6、t Improve- ment Proposal (DD Form 1426) appearing at the end of this document or by letter. FSC 9330 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-_ MIL-R-87L20A 73 W 777770b 0423684 b W AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM D445 A
7、STM D1553 Water in Insulating Liquids (Karl Fischer ASTM D1652 Epoxy Content of Epoxy Resins, Test for Kinematic Viscosity of Transparent and Opaque Liquids Method ) (Application for copies should be addressed to the American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 1910
8、3.) 3, REQUIREMENTS 3.1 Equipment. The equipment shall consist of the following: 3.1.1 Creel. of two one-pound standard cardboard spools of yarn. A textile payoff device capable of handling a minimum 3.1.2 Resin bath. of resin with metal or plastic rollers A metal container capable of containing one
9、 pint to 2 inches in diameter. 3.1.3 1st B-Stage oven. Capable of maintaining a temperature of 107 - + 14OC (225 - + 25OF). 3.1,4 2nd 3-Stage oven. Capable of maintaining a temperature of 204 + 27% (400 - + 50F), A typical oven would be 6 to 7 feet long. A typical oven would be 6 to 7 feet long. 3.1
10、.5 Curing oven, 2702 (500 - + 50F). Capable of maintaining a temperature of 260 - -t A typical oven would be 2 to 3 feet long. 3.1.6 Take-up rollers. Adjustable, capable of pultruding the rod at 15 to 25 feet per minute. or plastic with a rubber coating. The rolls shall be fabricated of metal 3.1.7
11、Analytical balance, (One-pan reading model such as Sartruious or Mettler Types.) 3.1.8 25 ml graduated cylinder. Pyrex No. 3022 or equivalent. 3.1.9 50 ml buret. 3.1,lO Magnetic stirrer and glass enclosed stirring element. 3.1.21 200 ml beaker. 3,1.12 100 ml graduated cylinder. 2 Provided by IHSNot
12、for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-R-87L20A 73 9777906 0423685 8 = . 3.1.13 250 ml flask. 3.1.14 Dies. Standard wire drawing dies: - Die 1 - 0.030 to 0.035 inch diameter. Die 2 - 0.025 to 0.027 inch diameter. 3.1 Materials 3.2.1 - Yarn. Conforming to S
13、pecification MIL-Y-87125, type II. 3.2.2 Epoxy resin. Conforming to the following requirements. 3.2.2.1 Moisture content. The moisture content of the resin shall be 0.4 percent by weight maximum. 3.2.2.2 Specific gravity. The specific gravity of the resin shall be 1.17 to 1.27 at 20C i l0C (68 + 1.8
14、F). - 3.2.2.3 Epoxide equivalent. The epoxide equivalent of the resin shall be 150 to 170 grams of resin, containing one gram equivalent. 3.2.2.4 Viscosity. poises at O to 10% (32 to 50F). The viscosity of the resin shall be 1.0 to 3.5 3.2.2.5 Storage stability. The resin shall meet all the require-
15、 ments of this specification after storage in the original unopened container at 16 to 35OC (60 to 95OF) for a period of one year from . the date of receipt. 3.2.3 Modified polyamine hardener. Conforming to the following requirements. 3.2.3.1 Specific gravity of hardener. The specific gravity of the
16、 hardener shall be 1.13 to 1.14 at 23 + 10C (73.5 + LOF). - - 3.2.3.2 Viscosity of hardner. The viscosity of the hardener at 23 - + l0C (73.5 - + 2OF) shall be 3600 to 5900 centiposes. 3.2.3.3 Amine value. The amine value of the hardener shall be 75 to 85 grams of hardener per gram equivalent. 3.2.3
17、.4 Storage stability. The hardener shall meet all the require- ments of this specification after storage in a sealed container at ambient temperature of 16 to 35OC (60 to 95F) and for a period of one year from the date of receipt. 3 Provided by IHSNot for ResaleNo reproduction or networking permitte
18、d without license from IHS-,-,-_ MIL-R-87120A 93 977770b OY23bBb T 3.2.4 Nitrobenzene. (Eastman Kodak Reagent No, 387, or equivalent,) 3.2.5 Glacial acetic acid. (Reagent grade). 3.2.6 Perchloric acid. 70-72 percent (Reagent grade ) I 3.2.7 Potassium acid phthalate. Primary standard grade. 3.2.8 Cry
19、stal violet indicator solution. 3.3 Procedure. 3.3.1 Setup. - a. b. d. e. f. C. h. i. j. k. Remove spools of yarn from container. Remove plastic film from spools of yarn. Install spools of yarn on creel. Install excess resin removal die (Die #1, paragraph 3.1.14.) Install compaction die (Die #2, par
20、agraph 3.1.14.) Turn on first B-stage oven and set temperature at 107 - + 14OC (225 + 25F). Turn n second 3-stage oven and set temperature at 204 c 27OC (400 + 50F). Turn-on curing oven and set temperature at 260 - + 27OC (500 - + 5oOj. Draw the yarn from the 2 spools on the creel simultaneously and
21、 with a smooth motion pass through the resin bath container, excess resin removal die, first B-stage oven compaction die, second B-stage oven, curing oven and drive rollers. A schematic of a typical rod pultruding facility is shown in Figure 1. Stabilize ovens. Mix resin of paragraph 3.2.2, and hard
22、ener of paragraph 3.2.3 by hand, stirring 1 to 2 minutes, formulation shall be as follows: Material Parts by weight Epoxy resin per 3.2.2 100 4- 1 Hardener per 3.2.3 - 28 7 1 1, Pour resin into resin bath and maintain at room temperature. 4 Provided by IHSNot for ResaleNo reproduction or networking
23、permitted without license from IHS-,-,-MIL-R-87120A (USAF) a .- a 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3.3.2 Operation. a, Turn on drive roller 20 i- 5 feet per minu and set speed to achieve a rate of e. b. c. Putrude 20 + 10 feet of rod
24、. d. Allow dry yak to run through facility and discard. The resin bath shall be changed and the dies cleaned at least once every one and a half hours. shall be discarded and new resin prepared per paragraph 3.3.1. The old resin 3.3.3 Rod inspection. After completion of the pultruding process, the ro
25、d shall meet the following requirements. 3.3.3.1 Separation. There shall be no separation of fibers. 3.3.3.2 Size. in diameter. The sample rod shall be between 0.024 and 0.031 inches 3.4 Certification. Ter, rods, fabricated in accordance with this process shall be subjected to certification tests of
26、 4.4. shall meet the requirements of 3.3.3. Each rod 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection. Unless otherwise specified in the contract, the contractor is responsible for the performance of all inspection requirements as specified herein. Except as otherwise specified in t
27、he contract, the contractor may use his own or any other facilities suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. The Government reserties the right to perform any of the inspections set forth in the specification where such inspe
28、ctions are deemed necessary to assure supplies and services conform to prescribed requirements. . 4.2 Calibration. All measurements shall be made using instruments whose accuracy has been verified in accordance with MIL-C-45662. instruments shall be calibrated every six months. staging ovens shall b
29、e calibrated for temperature and stability to - + 10C standard. All The curing and daily while operating and every six months against a master 4.3 Inspection conditions, Unless otherwise specified, tests shall be made at an atmospheric pressure of 28 to 32 inches of mercury and at a temperature of 2
30、2 to 26OC (76 - + 4OF) and a relative humidity of 40 to 60 percent. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-R-87120A 73 W 9777706 CIL123683 5 4.4 Special tests and examinations. 4.4.1 Process certification. Randomly select and remove a
31、12 i 1 inch test section from each of the first ten rods produced and subject the test sections to the following tests: - a. Separation (4.6.8) b. Size (4.6.9) 4.4.2 Raw material testing. 4.4.2.1 Yarn. conformance to 3.2.1. Each lot of yarn received shall be verified for - 4.4.2.2 Resin. A one quart
32、 sample of resin, from each lot of received, shall be subjected to the following tests: a., Moisture (4.6.1) b. Specific gravity (4.6.2) c. Expoxide equivalent (4.6.3) d. Viscosity (4.6.4) 4.4.2.3 Hardener. A one quart sample of hardener, from each lot received, shall be subjected to the following t
33、ests: a. Specific gravity (4.6.5) b, Viscosity (4.6.6 c. Amine value (4.6.7) 4,5 Quality conformance inspection. 4.5.1 Acceptance testing. Acceptance testing shall consist o in- process inspection and individual tests of 4.5.1.1 and 4.5.1.2. 4.5.1.1 In-process inspection. During the processing of ea
34、ch lot of rods, verify the following conditions: a. First B-stage oven temperature (3.3.lf) b. Second B-stage oven temperature (3.3.lg) c. Curing oven temperature (3.3.lh) d. Resin coating formulation (3.3. lk) 4.s.1.2 Acceptance tests. each 20 feet of rod produced and subject it to the following te
35、sts: Take a 6 to 12 inch section from between a. Separation (4.6.8 b. Size (4.6.9) 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-R-87120A 73 W 7779706 0423670 L W 4.6 Test methods. I 4.6.1 Moisture. Determine the moisture content in accordan
36、ce with ASTM D1553, Check for conformance to 3.2.2.1. 4,6.2 Specific gravity. Determine the specific gravity in accordance with the following procedure. Check for conformance to 3.2.2.2. 4,6,2,1 PreDaration of graduated cvlinder. The eraduated cylinder is Y cut off as ciose as possible to the“25 ml
37、mark usyng a silicon carbide glass cut off wheel or other suitable tool, rectininear as possible and the edges may be smoothed by grinding or fire polishing. The cut is made as 4.6.2.2 Rapid determination of densityor specific gravity. The graduate is standardized as indicated below. The true volume
38、, given to the nearest 0.01 ml is engraved on the base with a vibra-tool or indicated on a label affixed to the base and protected with a chemically inert coating of Krylon or a similar clear lacquer. these graduates are prepared, a unique identification number or letter for each one shall be affixe
39、d. If several of 4.6.2.3 Calibration of graduated cvlinder. a. Weigh the clean, dry and empty graduate to the nearest milligram and record this weight as W1 grams. b. Fill the graduate with room temperature distilled water so that the meniscus rises above the top of the graduate. other flat surface,
40、 larger than the cross-section of the graduate, across the top to “level off“ the liquid. Wipe the outside of the graduated with a lint-free absorbent tissue. graduate to the nearest milligram and record the weight as VIs grams. Immediately after removal from the balance, insert a thermometer in the
41、 water and record the temperature to the nearest degree as ts. Duplicate determinations should agree within + 0.03 grams. Carefully slide a glass plate .or Weigh the filled - 4.6.2.4 Density measurement of unknown material. a, Weigh the clean, dry and empty graduate to the nearest milligram and reco
42、rd this wieght as W1 grams. 8 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-b, Fill the graduate with the material to be measured which is in equilibrium with room temperature. the graduate so that the top of the meniscus is level with the top of t
43、he graduate. This may be accomplished, by leveling off the top of viscous liquids by using a wooden “tongue depressor“ or stirring rod. side of the graduate, wipe lint-free absorbent tissue and weigh the filled graduate to the nearest milli- gram. Record this weight as W2 grams and the temperature o
44、f the material to the nearest degree centigrade as tc. agree within + 0.05 grams. Fill Remove excess materials from the out- Duplicate determinations should 4.6.2.5 Calculations. a. Standardization. From Table I, obtain the apparent density of water in air, dt at the temperature, t, of the standardi
45、- zation. 20C, V, is then given by: The true volume of the H20 graduate at tvs - w1 vs= -7 b. Densitv of unknown material. The density (dt) of an unknown material at tempera- ture toc, is calculated by: c, Specific gravity of unknown material. The specific gravity, Where tc is the temperature at whi
46、ch the density of the unknown material is measured and ts is the temperature of the standard material. 9 I I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-? MIL-R-87120A 73 W 777770b 0423b72 5 W TABLE I, Apparent density of water weighed in air; ca
47、librated table for determining true volume of glassware at 20oc. Temperature OC 15 16 17 18 19 20 21 22 23 24 25 Apparent Density (dt) g./ml. O. 99793 O I 99780 0.99765 0.99751 O. 99734 O. 99718 0.99700 O. 99680 O. 99661 O, 99639 0.99618 Temperature OC 26 27 28 29 30 31 32 33 34 35 Apparent Density
48、( g./ml. O. 99594 O. 99570 O. 99545 O. 99519 O. 99492 O. 99464 O. 99435 O. 99406 O. 99375 O. 99345 4.6.3 Epoxide equivalent. Determine the epoxide equivalent in accordance with RSTM D1652. Check for conformance to 3.2.2.3. 4.6.4 Viscosity. Determine the viscosity of the epoxy resin using the Ubbeloh
49、de method in accordance with ASTM D445 at a temperature of 22 to 24OC (75 to 79OF). Check for conformance to 3.2.2.4. 4.6.5 Specific gravity. Determine the specific gravity in accordance with 4.6.2. Check for conformance to 3.2.3.1. 4.6.6 Yiscosity, form beaker (or equivalent) with spout and the beaker placed in a constant temperature bath at 24 to 26oC. When the sample temperat
