Single sided wall thickness measurement across piping, vessels, tanks, and structural components —
the essential data collection technique for corrosion monitoring, remaining life assessment, and
fitness-for-service evaluation.
What Is Ultrasonic Thickness Gauging?
Ultrasonic Thickness Gauging (UTG) uses a pulse-echo ultrasonic technique to measure the wall
thickness of a component from a single accessible surface — without requiring access to the
opposite face. A transducer coupled to the inspection surface transmits an ultrasonic pulse into
the material; the pulse reflects from the back-wall and returns to the transducer; the gauge
measures the time of flight and calculates the material thickness based on the acoustic velocity
of the material.
Key advantages of UTG:
Single-sided access — no need to access the internal surface
Non-destructive — no surface damage, no removal of insulation beyond probe access
windows (or combined with pulsed eddy current for through-insulation measurement)
Rapid data collection — suitable for extensive thickness survey programmes
Quantitative data — actual wall thickness readings, not just accept/reject
Applicable to a wide range of materials: carbon steel, stainless steel, aluminium, copper
alloys, and many plastics
Where We Apply UTG
Piping circuit corrosion monitoring — scheduled thickness surveys at defined monitoring
points
Pressure vessel shell, head, and nozzle remaining wall assessment
Storage tank shell thickness survey
Structural steel member thickness monitoring in corrosive environments
Heat exchanger shell thickness survey
Remaining life calculation — input data for corrosion rate and next inspection interval
determination