ULTRASONIC TESTING(UT)

What is this method?

Ultrasonic testing is a method of characterizing the thickness or internal structure of a test piece using high frequency sound waves to find the weld and base metal defects.

Why is this method?

Ultrasonic inspection can be used for flaw detection/evaluation, dimensional measurements, material characterization, and more. Ultrasonic testing can remotely generate ultrasound in materials without contact, leaves a very small footprint so that it can be applied to irregular geometries, and allows access to restricted areas via fiber optics.

It is used as non-contact and remote, allowing inspection of samples at high temperature, which can be seen during welding with restricted access. It enables inspection of small and complex geometries and high frequency capable of detecting very small flaws, Laser beam scanning method for full coverage of inspection samples

When is this method used?

Ultrasonic Examination uses high-frequency sound waves which are transmitted into a material to detect discontinuities or locate changes in material characteristics. Sound is introduced into the object being examined. Reflections from internal imperfections, areas of acoustic impedance, or varying geometrical surfaces are returned to a receiver.

Ultrasonic examination of welds shall be performed in accordance with BPV Code, Section V, Article 5, of ASME.

Roles and responsibilities:
  1. Conducts ultrasonic tests on fabricated metallic and nonmetallic parts and products to identify discontinuities, Reviews work orders, test procedure sheets, and product acceptance criteria to determine test specifications.
  2. Attaches specified crystal probe transducer to ultrasound test device and moves switch to actuate device.
  3. Calibrates and adjusts ultrasonic test equipment to required standards and settings, applying knowledge of ultrasonic testing procedures.
  4. Sprays coolant or other liquid over part to be tested, moves transducer over part to be tested, and observes CRT screen to detect patterns of discontinuity, such as cracks, inclusions, bonding defects, or porosity.
  5. Marks defective areas of part or product and prepares report of test findings.
  6. Identify defects in solid materials using ultrasonic testing techniques.