4. 5.3 Density of explosive charge. A minimum of two (2)
assemblies, representative of the transfer lead assemblies being
processed, shall be loaded and the densities determined to qualify
each press prior to its use in production. In addition, a sample
of two (2) assemblies shall be processed during the last portion
of each one (1) hour's production from each press and the density
determined as a control of each press during production.
If any defective assembly is found when inspection is
performed for control of a press, the press producing the
defective assembly shall be removed from production. Further,
that portion of production since the last control check shall be
returned to the contractor for corrective action.
All presses removed from production because of some fault,
may, after corrective action, be returned to production providing
they pass the qualification test above.
The following procedure shall be used to determine the density
of the explosive charge.
Weight empty lead cup (grams).
Measure bottom thickness (inches).
Measure wall thickness (inches).
Weight loaded lead cup (grams).
Measure height to top of charge (inches).
Measure outside diameter of loaded lead cup (inches}.
Calculate weight of charge (e-a). (grams).
Calculate height of charge (f-b) (inches).
j. Calculate volume of explosive charge (cubic
centimeters) = (.7854) x (16.39) x (g-2c) x (g-2c) x (i).
k. Calculate density of explosive charge (above).
per cubic centimeter) = (h/j).
If any assembly fails to comply with the density requirements
specified on the applicable drawing, it shall be classed
defective. This is a destructive test. Assemblies so tested
shall not be returned to the lot.
When weighing in water, use distilled water containing
suitable wetting agent, e.g. "Aerosol" (1cc per 250cc