1、I 13 AUGUST 1948 NATIONAL MILITARY ESTABLISHMENT SPECIFICATION This specification was approved by the Departments of the Army, the Navy, and the Air Force for use of procurement services of the respective Departments. A. APPLICABLE SPECIFICATIONS AND OTHER PUBLICATIONS A-1. XieczJicatiorls.-The foll
2、owing specifications, of the issue in effect on date of invitation for bids, form a part of this specification: U. S. ARMY SPECIFICATION Arms Ammunition? Contractors.1 50-0- ,l-General Specification for Ammunition except Small 100-2-Standard Specification for Marking Shipments by NAVY DEPARTMENT SPE
3、CIFICATION General Specifications for Inspection of Material.2 FEDERAL SPECIFICATION RR-S-366-Sieves; Standard, Testing. A-?. Other publications.-The following publications, of the issue in effect on date of invitation for bids, form a, part of this specification: BUREAU. OF SUPPLIES AND AWOUNTS PUB
4、LICATION Navy Shipment Marking Handbook.2 INTERSTATE COMMERCE COMMISSION REGULATIQNS Regulations for the Transportation of Explosives and Other Dangerous Articles, etc. B. GRADES B-l. This specification covers the following grades of manganese powder, as specified in the contraot or order (see par.
5、H-2) : Grade 1-99.5 percent total manganese. Grade 11-98.0 percent total maqganese. Grade 111-95.0 percent total manganese. c. MATERIAL AND WORKMANSP granulation in an inert atmosphere. C-l. Grade I.-Grade I manganese shall be ground to the proper - 1 Applicable only to Army purchases. 2 Applicable
6、only to Navy purchases. THIS DOCUMIENT CONTAINS -d-. PAGES, (No. 79) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2 D. GENERAJ, REQUIREMENTS D-I. See section E. E-1, The material shall comply with the requirements shown in E. DETAIL REQUIREMENTS t
7、able I. TAB LE I.- Det ail requirements. Grade I Grade II Grade III Percent Percent? Percent (minimum) (minimum) (minimum) 1 See par. R-3. 2 Mrrximum. 3?-I. Sige of lot,-Maximum, 1,000 pounds, Unless otherwise specified in the contract or order, the lot shall consist of material from not more than o
8、ne manufacturing batch of manganese powder. (See par. H-6.) F-2. Sampling.-Five containers shall be taken, at random, from the lot. If there are fewer than five containers in the lot, all the containers shall be taken for sampling. A %-pound sample shall be taken by means of a sampling thief, from e
9、ach container so chosen. The samples shall be placed in a clean dry container, stoppered tightly and mixed thoroughly to form a composite sample representative of the lot, The composite sample shall be labeled to identify the sample with the lot represented. I?-3, Inspection.- F-3a. Army.-Inspection
10、 shall be made in accordance with the requirements of U. S. Army Specification 50-0-1, and shall be made at thenpoint of delivery unless otherwise specified in the contract or F. METHODS OF SAMPLING, INSPECTION, AND TESTS order. F-3b. Navy.-Unless otherwise specified in the contract or order, inspec
11、tion shall be made at the point of delivery. E?-4. Tests,-The laboratory tests shall be made in accordancetwith the followin paragraphs. For Navy purchases, the tests shall be contract or order. F-4zt. Total manganese.-Place an accurately weighed portion of approximately 0.25 gm. of the sample in a
12、750-m1. Erlenmeyer flask and add 50-ml. of nitric acid solution having specific gravity. of 1.135. When tly! sample has dissolved, add 1 gm. of sodium bismuthate of at least 80-percent purity. Bring the liquid to. the boiling point and allow to boil for 3 to 5 minutes. If the precipitated oxides of
13、manga- nese or the color of permanganic acid does not persist through this boiling, add more sodium bismuthate and boil the mixture again. Acld sufficient sulfurous acid to clear the solution. Dilute the solution to a volume of 250 ml. with nitric acid solution having a specific made at a 8 overnmen
14、t laboratory unless otherwise specified in the (No. 79 1 I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. JAN-M-476A 68 7777906 0333927 5 3 gravity of 1.135, and cool to 10 to 15 C. Add 8 gm. of sodium bis- muthate and agitate the mixture briskly
15、for 1-minute. Dilute the mixture with 250 ml. d cold water and filter immedia%ely through a layer of prepared asbestos supported on a perforated porcelain plate resting in a large glass funnel, taking care not to allow the filter to run dry during the filtration. Wash the flask and filter with cold
16、3-percent nitric acid solution until the washings are entirely colorless, again taking care not to allow the filter to run dry. Treat the combined filtrate and washings immediately as follows: Add to the filtered solu- tion of permanganic acid an accurately weighed portion of approsi- mately 9.1 gm.
17、 of solid ferrous ammonium sulfate taken from a bottle of the well-mixed salt; stir the mixture briskly, and as soon as reduction is complete and the salt dissolved, titrate the excess of ferrous salt with approximately N/10 potassium permanganate solutioii. Obtain the permanganate value of the ferr
18、ous salt as follows: Pace 250 ml. of cold nitric acid solution having a specific gravity of 1.135 in a 750-ml. Erlenmeyer flask and add 2 gm. of sodium bismuthate; agitate the mixture vigorously for 1 minute. Dilute with, 250 ml. of. cold wat.er and immediately filter through a layr of prepared asbe
19、stos, as previ- ously described; add to the filtrate, first 50.00 mi. of approsiniatcly N/10 potassium permanganate solution, and .then an accurately weighed portion of approximately 3.0 gm. of the solid ferrous ammonium sulfate; dissolve the salt and titrate immediately with more of the N/10 potass
20、ium permanganate solution. Make the corrections for the excesses of permanganate used to cause the end point colors in both titrations. Calculate the percent total manganese as follows : 1 .O99 N(BC- D E W Percent total manganese= where N = normality of the potassium permanganate solution B=ml. of p
21、otassium permanganate solution required for reac- tion with D gm. of ferrous salt C= gm. of ferrous mlt added to reduce the permanganate formed from the manganese in the sample D =gm. of ferrous salt used for determining the permanganate value of the ferrous salt E=ml. of potassium permanganate solu
22、tion used in back titra- tion of the excess ferrous salt present after reduction of the permanganate formed from the manganese in the sample. W=gm. of sample. F-4b. Rree metallic manganese.-Determine the free metallic manganese content by the hydrogen evolution method, using a suitable apparatus for
23、 dissolving the ssmple and measuring the gas evolved. The apparatus shown on figure 1 has been found satisfactory, andits use is described below. Assemble the appazatus as shown on figure 1, attaching the various parts to suitable supports. Turn the three-way stopcock to the A position, raise the le
24、veling bulb until the meniscus of the water in the gas measuring buret is at the O-ml. inark, and turn the stopcock clockwise to the B position. Place 100 ml. of a 5- to 8- percent acetic acid solution, previously saturated with hydrogen, in the reaction flask, and attach the reaction flask to the a
25、pparatus by - means of the two-holed rubber stopper. Adjust the position of the- . J (No. 79) .- ! I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4 thermometer in the riibber stopper so that the bulb of the thermoiiieter dips into the acid solutio
26、n. Weigh accurately a portion of approxi- mately 1.0 gm. of the sample and wrap in cellophane or paper in such a manner as to make the following operations possible. Remove the reaction flask from the apparatus and place the wrapped sample iii t,he neck of the flask without allowing the sample to fa
27、ll into the acid. Reattach the reaction flask to the apparatus, again taking care not, to allow the sample to fall into the acid. Allow the sample to remain in tlie neck of the flask for at least 10 minutes or until the atmosphere above the acid becomes saturated with water vapor. Read the teiii- pe
28、rature and turn the three-way stopcock clockwise t.0 the C position. Cause the sample to fall into the acid by hitting the bottom of the reaction flask against the palm of the hand. Shake the flask to cause the wrapping on thc sample to open and the manganese to coiiie in contact- with the acid. As
29、the evolution of gas proceeds, lower the lovcling bulb so that the level of the water in the gas measuring buret. reinailis at approximately the same level as the water in the leveling bulb. When tlic reaction is complete, cool the acid solution in the reaction flask to its temperature prior to the
30、reaction and keep at this temperature for 10 to 1-5 minutes. Adjust the level of the water in the leveling bulb to the same height as the meniscus of the water in the gas measuring buret. Read the volume of gas in the buret and correct for any eiror in the graduation of the buret. Read the gas tempe
31、rature with ti thermometer close to the buret. Read the barometric pressure on a mercurial barometer accurate to 0.1 mm. and corrected for tein- perature. Calculate the percent free metallic manganese as f ollon-s : 273.1 X 0.2450 V (PL pi 760 (273.1 4- T) TP - Percent free inetallic manganese = wli
32、ere V=inl. of hydrogen evolved P= corrected barometric pressure p= T=gas temperature in degrees C. TV= gm, sample vapor pressure of water in min. at temperature T F-4c. Granulation. F-4c (1). Sice anaZvsis,-Nest the specified sieve or sieves, con- forming to Federal Specification RR-S-366, on a bott
33、om pan. Place n weighed portion of approximately 50 gm. of the sample on the upper sieve, cover Ghfs, and shake for 10 miriutes by hand or 5 minutes by meaiis of a single-eccentric type mechanical shaker which imparts to the sieves a rotary motion and tapping action of uniform speed of 300 rt= 15 gy
34、rations and 150 open the stopcock of the tube and permit the sus- pension to run into the cylinder. Close the stopcock and add approxi- mately 10 ml. of dispersing solution to the dispersing tube by means of a wash bottle, Move the brush up and down to loosen any man- ganese particles clinging to it
35、; then open the stopcock. Repeat this. procedure until both tube and brush have been thoroughly washed, as indicated by the absence of manganese particles in the dispersing solution when transferred from the dispersing tube to the cylinder. Adci dispersing solution to the cylinder of the Andreasen p
36、ipet until, with the pipet inserted in place, the suspension is brought to the mark. Replace the pipet by a thermometer. Note the temperature of the suspension and allow hot or cold tap water to flow over the outside walls of the cylinder until the temperature of the suspension is 25.0 =t: 0.5 C.; u
37、se the thermometer to stir the suspension vigorously during this process. Remove the thermometer and place the pipet with stopcock closed, in the cylinder, After making certain that the vent to the liquid chamber is closed shake the assembly in an inverted position for approximately 2 minutes. Take
38、care to assure a uniform dispersion by sufficient shaking and inverting of the assembly. Up- right the cylinder, open the stopcock of the pipet, and open the air .c.ent. Blow out any unmixed suspension which may be in the stem. Place the assembly in a constant temperature bath maintained at 25.0k0.6
39、 C., fasten firmly to a rigstand, and note the exact time. It is important that the minimum possible time elapse between the cessation of shaking and the noting of the time. Let the suspension stand for the calculated time. During this time make the connection between the reservoir and the pipet by
40、means of the length of flexible rubber tubing provided for this purpose. Seven seconds before the calculated time for taking the aliquot, start sucking up the sample as follows: Compress the bulb, close the open end of the Y tube, and control the rise of liquid in the pipet by slowly releasing the b
41、ulb. After the liquid has been drawn up to the 10-ml. mark of the pipet, close the stopcock of the pipet and open the end of the Y tube. To expel the liquid from the pipet, reverse the stopcock, close the open end of the Y tube, and compress the bulb gently. Wash the pipet bulb twice after the aliqu
42、ot has been expelled by opening the pinch clamp (fig. 2) and rillowing 2 to 3 ml. of solution to pass from the reservoir to the pipet bulb. Expel the washings in the same manner as the aliquot. Catch the aliquot and washings in a 50 ml. beaker. Transfer the aliquot and washings quantitatively to a t
43、ared Gooch crucible or fritted-glass crucible in position on a suction flask, using a rubber tipped stirring rod and a jet of dispersing solution from a wash bottle to effect complete transfer. Wash the contents of the crucible with three 5-ml. portions of wash solution and then three 5-ml. portions
44、 of acetone. .Air dry the crucible, then dry for 15 minutes at 100 to 105 C., cool in a desiccator and weigh. Calculate the increase in weight as percent suspended particles in the aliquot finer than 10 microns as follows: 100 AV Bw Percent finer than 10 microns= Provided by IHSNot for ResaleNo repr
45、oduction or networking permitted without license from IHS-,-,-JAN-H-qTbA b W 9999906 OLL3933 7 7 where A=gm. of suspened particles in aliquot taken at time calcu- B=ml. of aliquot taken (see par. F-4c (2) b) V=ml. of suspension in Andreasen pipet at start of test T=gm. of sample. lated for IO-micron
46、 diameter (see par. F-4c (2) b) F-5. Rejection and resubmission.-If the composite sample fails to comply with any of the specified requirements, the entire lot shall be rejected. The contractor shall have the option of having a partial or complete analysis made on each container in the lot at no exp
47、ense to the Government. The contractor may then remove defective portions of the lot and resubmit the lot for acceptance. G. PACKAGING, PACKING, AND MARKING FOR SHIPMENT G-1. Packing.-Unless otherwise specified in the contract or order, powdered maganese shall be packed in plain steel drums conformi
48、ng to the requirements of Specification 37D of Interstate Commerce Commission Regulations for Transportation of Explosives and Other Dangerous Articles, etc. Each drum shall have a removable head and shall be airtight when the cover is secured in place. The gross weight of the container and contents
49、 shall not exceed 110 pounds. G2. Marking.-Shipments shall be marked to insure safe handling as required by Interstate Commerce Commission Regulations for Transportation of Explosives and Other Dangerous Articles, etc, and in addition shipments for the Army shall be marked in accordance with the requirements of U. S. Army Specification 100-2; for the Navy, in accordance with the requirements of the Navy Shipment Marking Handbook. Any special marking shall be specified in the contract
