 |
|||
|
|
|||
| ||||||||||
|
|  MIL-W-50504A (AR)
prescribed . The hardness test shall be performed on the approximate
center of the bottom of the castings. The test shall be performed
as specified in 4.5.2 using equipment in accordance with 4.4.4.
3.5 Tension test.
3.5.1 Nose, malleable iron. Two nose castings from each heat
treatment batch, one of the hardest and one of the softest as
determined by 3.4.1, shall be subjected to this test. The test
shall be performed as specified in 4.5.3 using equipment in
accordance with 4.4.4.
3.5.2 Nose, ductile iron. To qualify the heat treatment, one
0.500 .010 inch diameter test specimen machined from a 1 inch
knock-off type keel block representative of each heat treat lot
shall be subjected to the test specified in 4.5.3 using equipment in
accordance with 4.4.4. In the case of the continuous heat treat
oven, one specimen shall be tested for each eight (8) hours of oven
operating time.
3.5.3 Base.
When malleable iron is used, two base castings
from each heat treat batch, one of the hardest and one of the
softest as determined by 3.4.3, shall be subjected to the tension
test in accordance with 4.5.4, to determine compliance with the
mechanical properties requirements of the applicable drawing. When
steel bases are used, two bases from each heat treatment or stress
relieved batch of 5000 or fraction thereof shall be subjected to the
tension test. The test shall be performed as specified in 4.5.4
using equipment in accordance with 4.4.4.
3.6 Microexamination. When ductile iron is used, a test lug
shall be cast representing the last metal poured from each ladle
treated with the modularizing agent. The test casting and
microexamination shall be in accordance with the microstructure test
described in ASTM-A-395.
3.7 Hydrostatic test. Each metal parts assembly shall be
subjected to the required constant internal hydrostatic pressure to
determine compliance with drawing requirements. Metal parts
assemblies which comply shall be stamped with the letter "H" as
indicated on the assembly drawing. The test shall be performed as
specified in 4.5.7 using equipment in accordance with 4.4.4.
3.8 Air pressure. Each body assembly that has passed the
hydrostatic test, as indicated by the letter "H" stamped on the
body, shall after completion of the drying cycle be subjected to a
4
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals