WELDING OPERATIONS I - OD1651 - LESSON 1/TASK 2
7.
Strengthening Riveted Joints in Armor Plate
a. Buttonhead Riveted Joints. To strengthen buttonhead riveted
joints in armor plate, a seal bead weld is recommended as shown
in figure 44, view B, on page 90. To apply the bead, the arc is
struck at the top of the rivet using a stainless steel electrode.
The electrode is held above the top of the rivet long enough to
melt approximately 1/2 inch of the electrode.
The electrode is
then moved along the curved surface of the rivet down to the
armor plate and around the edge of the rivet until the rivet is
completely welded to the armor plate.
Rivet joints in
homogeneous armor plate can be seal welded on both sides. Rivet
joints in face hardened armor, however, should be seal welded
only on the soft side of the plate.
b. Countersunk Rivet Joints.
Countersunk rivet
joints
are
sealed in the same manner as buttonhead rivet joints.
c. Advantage of Welding Rivet Joints.
Seal bead welding rivet
joints prevents the rivet head from shearing off, and the rivet
shank from punching through the plate upon a projectile impacting
on the armor plate.
8.
Testing of Welds
a. General. To ensure the satisfactory performance of a welded
structure, the quality of the welds must be determined by
adequate testing procedures.
The welded structure, therefore,
must be proof tested under conditions that are the same or more
severe than those found in the field.
Tests also serve to
determine the proper welding design; and forestall injury,
inconvenience, and untimely failure of materiel.
Generally,
there are two types of tests that can be performed to ensure the
satisfactory performance of the welded structure. They are, the
performance and the physical types of tests.
b.
Performance Tests.
Materiel repaired by standard welding procedures may be tested by
operating it to perform the functions for which it was designed.
For example, a weapon can be tested by firing an extra heavy
charge to determine the safety of the weld; a wheel vehicle can
be tested at high speeds over rough
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