NONDESTRUCTIVE TESTS AND
INSPECTIONS OF WELDS
Upon completion of this chapter; you will be able to do the following:
Describe the various types of nondestructive tests (NDTs) performed on
welded or brazed joints.
Discuss some of the equipment used to perform NDTs
Describe the various nondestructive testing symbols used.
Discuss the procedures for hydrostatic and operational tests of ships'
systems and piping systems.
Official (acceptance) tests must be performed by
personnel with current certification by the Naval Sea
A component is only as good as its weld. If the weld
is not sound and is subject to cracking under normal
penetrant, ultrasonic, and magnetic particle tests. If you
wear and use, then the material that has been welded is
are not certified, you may still take part in radiographic
of no use. Nondestructive tests (NDT) ensure that the
welds, castings, forging, and components are of good
tests (RTs) made under the direct supervision of a
quality. This chapter will discuss the various NDT
qualified radiographer if you have had formal training
When tests are specified, the specifications or
SO420-AA-RAD-010 (RAD-10), rules and regulations.
standards will outline in detail (1) which part is to be
Under these conditions, you may help prepare an item
inspected, (2) the testing procedure that must be used,
for testing and assist with radiographic exposures
(3) the extent of the part that will be inspected, (4) the
according to RAD-10 radiation protection rules.
qualifications of the persons making the test, (5) the
qualifications of the persons evaluating the results of
In the following pages, we will discuss the use of
the test, (6) the acceptance levels that the test must show,
radiography and ultrasonic testing (UT) and some of the
and (7) the materials and equipment to be used.
limitations of each. We will also provide some
Unspecified tests (tests not in the standards) may be
information on the uses and limitations of magnetic
made, but they cannot be considered as final acceptance
particle (MT) and liquid penetrant (PT) inspections.
tests unless they are specifically approved by the Naval
The last section of this chapter discusses hydrostatic
Sea Systems Command. Welders are not permitted to
testing of components.
inspect their own welds for final acceptance.
Before you begin any NDT of welds, you should
There is no standardized waiver of any specified
make a visual inspection (VT) to detect undercutting,
test regardless of the type of organization making or
weld, spatter, arc strikes, cracks, and other obvious
repairing the item. This should be understood by all