requirement.
2.1.3
Resolution Tests
In addition to the resolution test specified in AWS D1.1/D1.1M for
ultrasonic equipment, both near- and far-surface resolution tests shall be
conducted in accordance with the procedures specified for those
characteristics in paragraph EQUIPMENT QUALIFICATION REQUIREMENTS.
2.2
PROCEDURES AND METHODS
The pulse echo contact method with an A scan presentation shall be used for
the ultrasonic inspection of plate except when immersion techniques may be
approved for use in some applications. The procedures to be used for
personnel and equipment qualification, equipment calibration, and
inspection shall be submitted for approval at least 30 days before their
intended use. Approval will in no way affect the Contractor's obligation
to employ qualified personnel, equipment, and procedures, and to perform
the inspection as specified. The procedure description shall include the
following:
a.
Type of couplant.
b. Search unit characteristics including shape, nominal frequency,
diameter, type, and transducer angle if other than straight.
c.
Method and type of wave.
d. Equipment and accessories including manufacturer, model number,
date of manufacture, last date of calibration, and the manufacturer's
electrical, physical, and performance specifications.
e.
Decibel (dB) compensation system for distance-amplitude correction.
2.3
TEST FREQUENCY
The test frequency for ferrous materials shall be as specified in AWS
D1.1/D1.1M, Section: Inspection, subsection, Ultrasonic Equipment. For
other materials that are difficult to penetrate, any frequency within the
operating range of the equipment may be used. The effective depth of
penetration and sound beam divergency shall be demonstrated to the
Contracting Officer.
2.4
WAVE TYPES
The types of waves and conditions under which they shall be used shall be
as follows:
2.4.1
Longitudinal Waves
Longitudinal waves shall be used to locate, identify, and evaluate defects
in the various plate materials to be inspected.
2.4.2
Shear Waves
Shear waves may be used as a supplementary means of inspection to locate
questionable areas.
SECTION 05092A
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