DLA MIL-P-156B-1956 POTASSIUM NITRATE.pdf

1、MiJXARY SPECIFICATION POTASSIUM NITRATE This specijicatwn has been approved by the Deptment of Defense and is ma?: datory for we bg the Departments of the Army, uL8 Naw, and the Air Fm. 1. SCOPE 1.1 hpe. This specification covers po- tassiim nitrate for use in the manufacture of propellants, chemica

2、l munitions, and pyrotechnic compositions. 1.2 Ciassification. Potassium nitrate shall be of the following clases, as specified (see 6.1 and 6.2) : Class 1-for use in black powder and chemical munitions. Class 2-for use in pyrotechnic com- Class 3-for use in propellants. positions. . 2. APPLIC.4BLEM

3、)(=UMENTS 2.1 The following specifications and standards, of the issue in effect on date of invitation for bids, form a part of this specification : SPECIFICATiON mERAL . RR-S-366 -Sieves, Standard for MILITARY Testing Purposes JAN-P-113 -Packaging and Packing for Overseas Ship- menbBags, Shipping,

4、Textile, and Paper- Laminated MIL-P-156B 68 m 7777706 0113365 7 m -_. - 13 - 19-15- MIL-P-156B I 18 APRIL 1956 SUPERSEDING JAN-P-156A 9 JULY 1946 MIGG-2550 -General Specification for Ammunition Ex- cept Small Arms Ammunition STANDARDS MILITARY MIGSTD-129-Marking for Shipment . andstorage (Copies of

5、specifications, standardri, drswinga, and publications, required by contradors in connection with specific procurement functions ahould be ob- tained from the pramring activity or (LB directed by the contracting officer.) 2.2 Other publications. The following document forms a part of this specificat

6、ion. Unless otherwise indicated, the issue in effect on date of invitation for bids shall apply. INTERSTATE COMMERCE COMMISSION 49 CFR Il-lr- 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-P-LShB 68 W 9997906 03113370 O Wb MIL-P-156B with the

7、mercury in the reading and com- pensatj:-,g tubes on a level, the mercury in the rec-: .ng tube marks the calculated vol- ume of t!:e air. Paste a strip of paper on the tube so 25 to mark the height of the mercury in the cc-3pensating tube. Consider this as the stand;.rd volume of air with which eve

8、ry volume of gas, to be measured, is compared. (Note. Tile use of dry air tends to form a scum around the reading level of the compensating tube, thus requiring frequent restandardization of the nitrometer. Tnis scum is caused by reaction of oxygen in the air with mercury, or by impurities. Dry nitr

9、ogen eliminates the condition and should be used, if available. A half drop of sulfuric acid will also prevent this scum.) 4.4.12.1.2 Potassium nitrate method. Re- crystallize three times, from 95-percent alco- hol, a sample of reagent grade potassium nitrate, and grind this to pass through a U. S.

10、Standard No. 100 sieve. After drying at 135O to 150OC. for 2 or 3 i:crurs, weigh a portion of exactly 1 gm. into a small weighing bottle and transfer this portion to the cup of the generating bulb, Wash the potassium nitrate into the geiierating bulb by means of eight to ten portions of 99.5 +- 0.5-

11、percent nitrogen-free sulfuric acid cooled to approximately SOC., using a tctal Yo!ume of Y5 mi. of the acid. Fith the lower stopcock U the generating bulb open an the mercury reservoir low enough to maintain a slightly reduced pressure in the generating bulb, shake the sample until most of the gas

12、has been generated. Adjust the mercury reservoir until the mercury drops nearly to the lower shoulder of the generating bulb. Close the lower stopcock and shake the bulb 1-igorously for 3 minutes. Replace the bulb on the rack, open the lower stopcock, and allow the tube to stand for 5 minutes, the l

13、evels in the generating bulb and reservoir being approximately the same, having previ- ously introduced desiccated air into the com- pensating tube as described in 4.4.12.1. Close the Iower stopcock, and shake the gen- eating bulb for 1 additional minute. Trans- fer the gas to the reading tube, and

14、adjust the levels of the mercury in the reading and compensating tubes to approximately the same height. Allow the gas to stand for approximately 20 minutes, to permit equali- zation of the temperature. With a sulfuric acid U-tube leveling device make careful ad- justments, so that the mercury in bo

15、th tubes is at the same level, and the mark in the reading tube is at the 13.85 mark (the per- centage of nitrogen in potassium nitrate). Make a mark on the compensating tube to show the volume occupied by the air equiva- lent to the volume of nitric oxide gas liber- ated from exactly 1 gm. of potas

16、sium nitrate. (This mark may be made on a strip of gummed paper attached to the compensating tube.) (Note 1. In order to avoid any doubt regarding the purity of the potassium nitrate, it is desirable to check the standardization obtained by the use of potassium nitrate by means of the absolute metho

17、d. If the agreement is within one or two hundredths of one percent, the potassium nitrate can be con- sidered as of satisfactory quality and used in sub- seqzent permdic standardizations. It has been found by actual experimentation that the solubility of nitric oxide in suIfuric acid, of the strengk

18、h pre- scribed, is so small that no correction need be applied to bring the value in agreement with. the mark set by the absolute method.) (Note 2. If the nitrometer is standardized by both the absolute and potassium nitrate methoOs, the re- sults may nor; be in agreement 5s 0.01 to 0.04- persent ni

19、trogen diie to expansion of the brass applying. the brass scale correction corresponding to the temperature (see 6.4) .) 4.4.12.2 Procedure. Crush a portion of approximately 3 gm. of the sample so that it will pass through a U. S. Standard No. 100 sieve, and dry for 2 hours at 150OC. Accu- rately we

20、igh approximately 1.0 gm. of the dried sample and transfer it to the cup of a standardized 5part nitrometer (duPont o equivalent). Measure into a small graduate, 25 ml. of nitrogen-free 94.5 t 0.5-percecz sulfuric acid cooled to approximately .5C. Wash out the weighing bottle into the ni- trometer c

21、up with 5 ml. of the eiilfuric acid. Lcwer the mercury Yeservir sufi-cirntly to inaintain a reduced 2ressure iii the geiierat- ing bulb. Open wide the upper stopcock und open the lower stopcock siifficici?tly to draw the acid mixture into the generating bulb. Make successive 4-ml. rinsings with the

22、rest h.- ,.neter %, scale. Such difference may be removed by Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- *. flIL-P-15bB 68 779770b 0113371 2 of the sulfuric acid until it has all been drawn in. Close the upper stopcock, leaving the lower one ope

23、n, and adjust the mercury reservoir just low enough to maintain a slightly reduced pressure in the generating bulb. Shake the bulb gently until most of the gas has been generated. Lower the mer- cury reservoir until the level of the mercury in the generating bulb is at the height of the lower should

24、er, then close the lower stop- cock and shake vigorously for 3 minutes. Replace the bulb on the rack, open the lower stopcock, and adjust the mercury reservoir until the mercury in the generating bulb is at approximately the same height as the mercury in the reservoir. This will bring the pressure i

25、nside the generating bulb to approximately one atmosphere, and the solu- bility of the nitric oxide gas in the sulfuric acid will be normal. Close the lower stop cock and shake the bulb vigorously for an additional 1 minute. Transfer the gas to the measuring tube and adjust the levels of the mercury

26、 in the compensating and measuring tubes to approximately the same height. Let the gas stand for 20 minutes in order to per- mit equalization of the temperature of the gas in the two tubes, and adjust the mer- cury levels closely with a sulfuric acid U- tube leveling device, the mercury level in the

27、 compensating tube being at the standard volume mark. Calculate the percent nitro- gen as follows : i Percent nitrogen = R W - where : R = reading of the measuring tube. W = weight of sample, in gm. 4.4.13 Granulaton. Nest the specified sieve or sieves (see table II) on a bottom pan. Place a weighed

28、 portion of 100 gm. of the sample on the upper sieve, cover the sieve and shake the assembly for 10 minutes by hand, or for 5 minutes by means of a mechanical shaker, geared to produce 300 and the fact that the Government may have formulated, furnished, or in any way supplied the said drawings, spec

29、ifiba- tions, or other data is not to be regarded by implica- tion or otherwise as in any manner licensing the holder or any other person or corporation, or con- veying any rights or permission to manufacture, use or sell any patented invention that may in any way be related thereto. Preparing Activity : Custodiane: Army-Ordnance Corps Army4rdnance Corps Navy-Bureau of Ordnance Air Force Other interest: Army-c - I_ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-