Downloaded from https://www.everyspec.com MIL-STD-322B 20 March 1984 5. DETAILED REQUIREMENTS 5.1 Test equipment, procedures, and ‘safety precautions. Details in this section ampl’ify or modify the specified test equipment and procedures in MIL-STD-331. Details of the Bruceton and the OSTR methods are given by the referenced documents. Additional information is given in Chapter III of the Electric Initiator Handbook (see 2.2d) as the method applies to the input energy supplied by the capacitor discharge. Dry ice refrigeration may be used for low temperature conditioning provided that the carbon dioxide. gas has no significant effect upon the test samples.
Since test samples are explosives, adequate safety precautions shall be provided during all handling and testing operations to prevent injury to personnel. The.person in charge of this test shall know the design and operation of the test samples thoroughly. Reraoval of the samples from a test fixture shall be accomplished by an experienced person(s) following written approved procedures. All electrical and heating fixtures required for any of these tests &.hallmeet safety requirements speci- fied liy the testing activity. \ 5.1.1 Sensitivity to initiation. Equipment shall include standard firing fixtures and a suitable electrical input source.
Electrical input source and equipment already developed and identified in Electric Initiator Handbook (2.2d) shall be acceptable. Output measurements shall be made by using Test 301 (steel dent), 302 (lead disc), or 303 (aluminum dent) in MIL-STD-331”. Input,energy variations shall be as follows: .. a. Constant current for pulse times of 1 u sec (micro-second), 10 u see, 100 u see, and 1000 u.sec. b. Constant “voltage for pulse times of 1 m sec (mini-second), 10”m see, and 100 m sec.. c. Capacitor discharge using capacitors of 0.0022 UF (microfarad); 0.01 uF, 0.04 uF, 1 uF, and 16 uF. ,In all tests, the increments shall be in log units (i.e.
, volts, amps, etC.) and no sample shall be tested at more than one firing level. All misfires shall be destroyed. The method of.analysis shall either be’the Bruceton or the”OSTR technique. 5.1.1.1 Bruceton technique. Twelve hundred sixty samples shall be used to conduct the sensitivity tests: with 100 samples for each group and 20 extra available for use in estimating the proper step,variation of the inPut energY to obtain valid data for the required calculations. Details of the method with sample calculations are given in AMP Report No. 101.1R SRG-P No. 40 (see 2.2a) and NAVORD Report No. 2101 (see 2.1).
The 50% firing point (level) with its standard deviation along with the “all-fire” and”’’no-fire” levels so calculated shall be recorded in Figure 8. 5.1.1.2 OSTR technique. Twelve hundred samples shall be used in this alternate technique to conduct the sensitivity tests using 100 samples ir.each I i group to obtain the 10%, 50% and 90% functioning levels. Details of the method 1 5