WELDING OPERATIONS I - OD1651 - LESSON 1/TASK 2
9.
Troubleshooting Welds.
a. Thus far, this lesson has described the processes for
identifying electrodes, the automotive welding processes, the
types and techniques of joint design, the procedures for welding
armor plate, and the methods of destructive and nondestructive
testing of welds.
This material provided the basis for the
troubleshooting of welds to be discussed in the succeeding
paragraphs. Each of the troubleshooting procedures discussed are
based on specific malfunctions detected as a result of visually
examining welds. The troubleshooting procedures discussed below,
therefore, are based on a total of five specific malfunctions
most likely to be encountered in a maintenance unit in the field.
For further information on other troubleshooting procedures refer
to TM 9-237.
b. Procedure.
Listed below are the procedures that the welder
would follow in troubleshooting a weld upon detecting the
malfunction indicated.
(1) Poor Fusion.
Step 1. Check the diameter and the length of the electrode. The
electrode selected should be of a size that will permit its
reaching the bottom of the joint to obtain adequate penetration
and good fusion.
Step 2. Check the welding current setting.
Use sufficient
welding current to permit adequate deposit and penetration of the
weld.
Heavier plates require higher current for a given
electrode than light plates.
Step 3. Check the welding technique used.
Be sure that the
weave is wide enough to thoroughly melt the sidewalls of the
joint.
Step 4. Check the preparation of the joint. The deposited metal
should fuse with the base metal and not curl away from it or
merely stick to it.
(2) Poor Penetration.
Step 1. Check to see if the electrode is designed for the
welding position being used.
Electrodes should be used for
welding in the position for which they were designed. Be sure to
allow the proper root openings at the bottom of a weld. Use
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