1、MIL-A-LbbC 13 m 9999906 0290786 5 m MIL-A-166C 6 January i975 SUPERSEDING 28 August i968 AND MIL-A-00166B (MU) JAN- A- l 6 6A 31 October 1945 MILITARY SPECIFICATION AMMONIUM PICRATE (EXPLOSIVE D) .Thi%- shall also be submitted whenever there is a lapse in production for a period in excess of 90 days
2、 or whenever a change occurs in manufact iring process, materiaL used, drawing, specification or source of supply as to significantly affect product uniformity as determined by the Government. Prior to submission, the contractor shall inspect the sample to the degree necessary to assure that it conf
3、orms to the requirements of the contract and submit a record of this inspection with the sample. A sample containing known defects will not be submitted unless specifically authorized by the Contracting Officer. (see 6.1). subjected by the Government to any or all of the examinations or tests specif
4、ied in 4.3 and 4.4 of this specification and any or all requirements of the applicable drawings. 4.2.2 Inspections to be performed. The sample will be 4.2.3 Rejection. If any sample fails to comply with any of the applicable requiremepts, the first article quantity shall be rejected. its inspection
5、upon any failure of a sample to comply with any of the stated requirements. The Government reserves the Tight to terminate 5 Licensed by Information Handling ServicesMIL-A- i66c 4.3 Quality Conformance Inspection 4.3.i Lot formation. A lot shall consist of one or more batches of ammonium picrate pro
6、duced by one manufacturer in accordance with the same specification or same specification revision under one continuous set of operating conditions. Each batch shall consist of that quantity of ammonium picrate that has been subjected to the same unit chemical or physical mixing process intended to
7、make the final product homogeneous. The product shall be submitted for inspection in accordance with MIL-STD-105. The criteria and procedures for the assignment of lot numbers shall be in accordance with MIL-STD-1168. 4.3.2 Examination. Sampling plans and procedures for the following classifications
8、 of defects shall be in accordance with MIL-STD-105 (ABC-STD-105). Contractors sampling plans, if used, shall be approved by the Government and shall provide as a minimum, the protection afforded the Government by the sampling plans in MIL-STD-105. Continuous sampling plans in accordance with MIL-ST
9、D-1235 may be used if approved by the procuring activity. Also, at the option of the procuring activity, AQLs and sampling plans may be applied to the individual characteristics listed, using an AQL of 0.40 percent for each Major Defect and an AQL. of 0.65 percent for each Minor Defect . 4.3.2.1 Woo
10、den box or fiberboard carton, prior to closing (see Drawing (dwg) 7548644, 7548645). Categories Defects Method of Inspection Critical: None defined. Major:. AQL 0.65 percent 101. Liner pierced or torn.Visual 102. Liner improperly closed.Visual 103. Foreign materoOOOoOOOVisual Minor: None defined. 6
11、I ;- L. i_ Licensed by Information Handling ServicesLicensed by Information Handling ServicesTABLE III CLASSIFICATION OF DEFECTS Category Surface moisture and volatiles content Total moisture content Ammonium picrate purity Sulfates (as sulfuric acid) Chloroform soluble impurities Water insoluble ma
12、terial Irrant contaminants (as chlorine) Ash Acidity and alkalinity (as picric Color Granulation Bulk Density acid or ammonia) Defect Ma j or Major Maj or Major Maj or Ma3 or Major Maj or Ma j or Ma j or Maj or Major vernment reserves the right to inspect the contractors equipment and determine that
13、 he has available and utilizes correctly, measuring and test equipment of the required accuracy and precision and that the instruments are of the proper type and range to make measurements of the required accuracy. Commercial inspection equipment, shall be employed where applicable for all tests and
14、 examinations specified in 4.3 and 4.4, The contractor is responsible for assuring proper calibration procedures are followed. Government approval of all inspection equipment is required prior to its use for acceptance purpose. 40304 Inspection Equipment. .Th Licensed by Information Handling Service
15、sMIL-A-LbbC 13 7997906 0290794 4 MIL-A-166C 4.4 Test Methods and Procedures (see 6.3) 4.4.1 Moisture 4.4.1.1 Surface molsture and volatiles (applicable to class 1 only). An accurately weighed sample of approximately 5 g shall be transferred to a tared dish approximately 7 cm in diameter. The dish sh
16、all be shaken gently to distribute the sample evenly over the bottom. The dish shall be placed in an oven, maintained at 90 C 2 degrees Centigrade (OC) until the sample reaches constant weight (approximately 2 hours). The dish shall then be removed, cooled in a desiccator containing- anhydrous calci
17、um chloride and weighed. Determine the loss in weight, and calculate (by weight) the percentage of surface moisture and volatiles in the sample as follows: Percent surface moisture and volatiles = A x 100 B Where : A = Loss in weLght, in g B = Weight of sample, in g 4.4.1.2 Total moisture content (a
18、pplicable to class 2 only). The total moisture shall be determined in accordance with method 101.4 of MIL-STD-650, except methyl alcohol shall be used as the solvent . 4.4.2 Purity of ammonium picrate 4.4.2.1 Apparatus. Weight buret, self supporting, 10 ml capacity; Magnetic stirrer and teflon-cover
19、ed bar; Erlenmeyer flask, 125 capacity or i50 ml beaker; Analytical balance; Incadescent microscope lamp. 4.4.2.2 Reagents 4.4.2.2.1, 0.1 N perchloric-acetic acid; prepared by slowly adding 5.6 ml 70% perchloric acid to 21.5 ml acetic anhydride (swirl constantly and cool, while mixing in an ice bath
20、; maximum temperature 20C). Dilute resulting mixture with 250 ml. glacial acetic acid, mix and make up to 500 ml with more glacial acetic acid. Keep container tighly closed and do not use for 18 hours. 9 Licensed by Information Handling Services- 4.4.2.2.2 Crystal, violet indicator solution, prepare
21、d by dissolving 1.0 g of indicator in 100 ml glacial acetic acid. Keep container tightly closed. Weigh accurately 100 mg, to nearest O.lmg, of potassium acid phthalate in a beaker and add 100 ml of acetic acid and 1 drop of crystal violet indicator. Heat gently to dissolve and titrate immediately wi
22、th perchloric-acetic acid solution to a blue end point. Add titrant dropwise. Use microscope light shining through the solution to make a spot on a white background. Spot will change from pink to predominent blue at the end point. As endpoint approaches, the buret will deliver too much solution in o
23、ne drop, so drops must be split to prevent over running. A stainless steel spatula is a convenient means for splitting drops and adding them to the sample solution. Calculate the normality of the perchloric-acetic acid solution as follows: 4.4.2.3 Standardization of Perchloric-acetic acid solution.
24、Normality of perchloric-acetic acid solution = 204.2 X V titrant, in ml Use the average of triplicate values for final Normality of perchloric-acetic acid solution. 4.4.2.4 Procedure. Weigh accurately 100 mg, to nearest 0.1 mg, of the dried sample into a 250 ml pyrex beaker. Run samples in quadrupli
25、cate. of indicator (see 4.4.2.2.2). Heat gently on a magnetic stirrer hot plate. When sample is dissolved, titrate dropwise with standardized perchloric-acetic acid solution to blue end point. Again use microscope lamp and spatula to make end point clearer. The percent purity of ammonium picrate sha
26、ll be calculated as Add 100 ml of acetic acid and 1 drop Percent purity of ammonium picrate = 24.61 X A X B used in the titration, in ml B = Final Normality of the perchloric-acetic acid solution W = Weight of the sample on a moisture-free basis, in g Licensed by Information Handling ServicesNIL-A-L
27、bbC 13 W 77777Ob 027077b W MIL-A-166C g=. Final percent purity of ammonium picrate shall be the average of the four determinations. (1) Allowance shall be made for the high coefficient of cubical expansion where all titrations employ solutions in glacial acetic acid. It shall be assumed that the 0.1
28、N solution of perchloric acid, in glacial acetic acid.has the same coefficient of expansion as acetic acid itself, namely, 0.0011 ml per ml per OC. The temperature.of the titrating solution at the time of titration shall b read on a thermometer attached to the buret. The observed volumes of titratin
29、g solution shall be corrected to an arbitrarily chosen standard temperature of! 2OoC by a factor of 0.1lpercent per OC. 4.4.3 Sulfates 4.4.3.1 Photometric method. If the sulfate content is estimated to be not more than 0.065 percent, the photometric method for the determination of sulfate shall be u
30、sed. An accurately weighed sample of approximately 2.5g shall be weighed into a i50 mlbeaker. alcohol and i5 ml of 1N hydyochloric acid (HC1) shall be added and the mixture warmed on a steam bath until solution is complete. The solution shall be poured into a LOO ml volumetric flask and di-luted to
31、the mark with distilled water. The solution shall be mixed thoroughly. This solution shall be identified as OA1l. Ten ml of solution “A“ shall be measured, using a 10 ml pipet, and transferred int6 a clean colorimetric tube. One ml of distilled water shall be added from a buret and mixed thoroughly.
32、 This shall be.the blank. Ten ml of solution “A11 shall be measured using a 10 ml pipet, into another colorimetric tube and 1 ml of acidified i percent barium chloride added. The contents shall be mixed thoroughly and allowed to stand for a minimum time of 3 minutes but not longer than 10 minutes. T
33、his shall be the sample solution. The outer surfaces of the colorimeter tubes shall be wiped with a clean cloth prior to placing the tubes in the comparison slots. The dial shall be set so that the blank reads 100 percent. The sample shall be shaken and a reading made within 30 seconds. Check readin
34、gs shall be made, and 100 percent reading shall Fifty ml of 95 percent 11 Licensed by Information Handling ServicesMIL-A-LbbC 13 a 77777Ob 027777 T a MIL-A-l66C be checked each time. The percent sulfate in the sample shall be read directly from the accompanying light transmission curve. This curve s
35、hall be prepared by adding known quantities of sulfate to sulfate-free ammonium picrate, carrying these samples through the procedures and plotting the transmittancy readings against percent sulfate as sulfuric acid (H2SO4) l. For this determination, the illumination switch shall be set at low and a
36、 red filter used. If the results indicate that the sulfates are below 0.065 percent, this value shall be reported as the final sulfate. 4.4.3.2 Gravimetric method. The gravimetric method shall be used if the sulfate content by the photometric method is above 0.065 percent. An accurately weighed samp
37、le of approximately 5g shall be dissolved in 300 ml of hot 95 percent ethyl alcohol, filtered through a medium porosity filtering crucible and washed with 50 ml of hot alcohol. The filtrate shall be evaporated to dryness and residue retained. The filtering crucible shall be washed with 60 ml of dist
38、illed water at 10C, and the filtrate added to the residue from the alcohol evaporation. One hundred forty (140) ml of distilled water and 1 drop of concentrated HC1 to dissolve all ammonium picrate shall then be added to the residue from alcohol evaporation, and sulfate precipitated with barium chlo
39、ride in the customary manner. Calculate the percent soluble sulfates (calculated as HSO) as follows: Percent soluble sulfates (calculated as H2SO4) = u W Where : A = Weight of precipitate, in g W = Weight of sample, in g 12 . -. -. Licensed by Information Handling ServicesThe filtering crucible, fro
40、m which water soluble sulfates have been extracted, shall be dried to constant weight at lO5OC and then extracted with 100 ml of a hot 10 percent solution of ammoniacal ammonium acetate (300 ml ammonium hydroxide (NH4OH), 150g ammonium acetate (NHCZHO), 1200 ml distilled water), followed by washing
41、with 75 ml of warm distilled water and finally with alcohol. Determine the loss in weight by drying the filtering crucible at 105OC to constant weight and calculate the rcentage of lead sulfate (calculated as H2SO4) as follows: (37 Percent lead sulfate (calculated as H2SO4) = 32.3.A w Where : A = Lo
42、ss of weight, in g W = Weight of sample, in g The sum of sulfuric acid as lead sulfate and as soluble sulfates shall be reported as total sulfuric acid. (2) sodium sulfate are insoluble in 95 percent ethyl alcohol while ammonium sulfate is slightly soluble. The above procedure shall be necessary sin
43、ce lead sulfate and 4.4.4 Chloroform soluble impurities (applicable to class 1 only). A sample of log shall be finely ground and placed in a beaker with 50 ml. of chloroform. The sample shall stand 30 minutes with frequent stirring, filtered through a dry filter into a tared 100 ml flask, washed wit
44、h 25 ml of chloroform and the washings added to the filtrate. The chloroform shall then be distilled off through a condenser and recovered for further use. The flask shall be dried for 1 hour at 100C, cooled in a desiccator and weighed. Calculate the increase in weight as percentage of chloroform so
45、luble impurities after subtracting the weight increase due t.0 the picric acid, if present, (see 4.4.8) as follows: Percent chloroform soluble -impurities = AA-B) X 100 W Where : A = Weight of residue in flask, in g B = Weight of increase due to picric acid, in g W = Weight of sample used, in g Lice
46、nsed by Information Handling ServicesMIL-A-16 6C 4.4.5 Water insoluble material. An accurately weighed sample of approximately log shall be dissolved in i50 ml of boiling distilled water, boiled for 10 minutes,filtered through a tared medium porosity filtering crucible and the residue washed several
47、 times with hot distilled water. The crucible shall be dried for 1 hour at 100C, cooled in a desiccator and weighed. Calculate the increase in weight of the crucible to percent water insoluble material. Percent water insoluble material = (B-A) x 100 W Where : A = Weight of tared crucible, in g B = W
48、eight of tared crucible and residue, in g W = Weight of sample, in g 4.4.6 Irritant contaminants (as chlorine) (applicable to class 1 only). A sample of 1OOg (weighed to the nearest 0.001g) shall be finely ground and placed in a 400-ml beaker with i50 ml of ether. The sample shall stand for 1 1/2 ho
49、urs with occasional stirring and then be filtered through a sintered glass filtering funnel and washed well with 200 ml ether. Forty ml of a 5 percent alcoholic sodium hydroxide (NaOH) solution shall be added to the filtrate, the solution placed on a steam bath and evaporated to approximately 20 ml. The filtrate shall be washed with distilled water into a large nickel crucible and carefully taken to dryness on a hot plate. When cool, approximately 4g (weighed to the nearest 0.001g) of sodium peroxide shall be added to the residue in the nickel crucib
