WELDING OPERATIONS I - OD1651 - LESSON 1/TASK 2
face hardened metal.
This type weld must be ground down flush
with the base metal before welding of the strap to reinforce the
damaged area. After grinding, the weld is then visually examined
to check for proper penetration, craters, cracks, and evenness in
the weld metal grain.
(3) Destructive and Nondestructive Tests.
In the following
subparagraphs, we will describe a total of six tests, three
destructive and three nondestructive.
These six test are the
ones most likely to be performed in maintenance units in the
field and depot maintenance operations.
If more information on
other tests is desired, it is provided in TM 9-237.
(a) Destructive Tests.
1 Guided Bend Test.
a This type test serves to determine the quality of the
weld metal at the face, the root of the welded joint, and the
degree of penetration and fusion to the base metal. These tests
are made on a jig as shown in figure 45, view A, on the following
page. This jig can be fabricated to any size desired in a field
maintenance company machine shop.
b To perform this test, the test specimens must be
machined from welded plates to a thickness within the capacity of
the bending jig.
The specimen is then placed across die
supports.
The weld on the specimen must be centered on the U
portion of the die.
The plunger is then lowered onto the
specimen from above by a hydraulic jack or other device to force
the specimen into the U portion of the die.
To fulfill the
requirements of this test, the specimen must bend 180 degrees and
have no cracks greater than 1/8 inch on its surface.
c Both a face bend and a root bend test of weld, as shown
in figure 45, view B, can be performed on this jig. To perform
the face bend test, place the face of the weld facing down on the
jig. The root bend test is performed by placing the specimen on
the die with the face of the weld facing up.
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