MIL-DTL-398D
porosity porcelain filtering crucible, which has been ignited at
700 + 20 degrees C, and tared to the nearest 0.1 milligram.
Transfer any remaining insoluble material from the beaker to the
crucible with the aid of a stream of acetone from a wash bottle.
Wash the material remaining in the crucible three times with 20
ml portions of acetone and aspirate until the odor of acetone is
no longer noticeable. Dry the crucible in an oven at 105 + 5
degrees C for thirty minutes, cool in a desiccator and weigh to
the nearest 0.1 milligram. Reserve the crucible and contents for
determination of inorganic insoluble materials given in 4.7.4.
Calculate the acetone insoluble material as follows:
Percent acetone insoluble material = (A-B) x 100
W
Where:
A = The
final weights of the acetone insoluble material
and
the crucible in grams.
B = The
tare weight of the crucible in grams.
W = The
RDX sample weight in grams.
4.7.4 Determination of inorganic insoluble material. At a
temperature of approximately 700 degrees C., the material in the
crucible obtained as directed in 4.7.2 shall be ignited, cooled,
and reweighed. The increase in weight over the original tare
weight shall be calculated as percent inorganic insoluble
material.
4.7.5 Determination of acidity. A 10 + 0.5 gram portion of
the sample, weighed accurately to the nearest 0.01 gram, shall be
transferred to a 400 ml beaker, 150 ml of acetone added, and
heated on a steam bath until the RDX is completely dissolved.
One-hundred ml of distilled water shall be added and the mixture
cooled and titrated with 0.05 N. sodium hydroxide using
phenolphthalein or methyl red indicator. A blank shall be run
and the results of the titration of the sample corrected for
acidity of reagents. The acidity shall be calculated on a dry
basis to percent nitric acid or acetic acid for Types I or II,
respectively.
CALCULATIONS FOR ACIDITY
Percent Nitric Acid = 6.3 (S-B) N
W
Percent Acetic acid = 6.0 (S-B) N
W
Where:
S = ml NaOH used in test determination
B = ml NaOH used in blank determination
13
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business