HotSense Time-Of-Flight-Diffraction (TOFD)

HotSense Time-Of-Flight-Diffraction (TOFD)

Minimise operational risk and maximise productivity with on-stream asset intelligence

Minimise operational risk and maximise productivity with on-stream asset intelligence

Time-of-flight diffraction transducers for on-stream weld root corrosion and crack/defect detection for use in applications across refining, oil & gas, energy, nuclear, aerospace, and process sectors.



  • Built on the award winning HotSense ultrasonic platform powered by the proprietary Ionix HPZ piezo-ceramic, and offering increased heat resilience
  • -55 to +350 °C [-67 to +662 °F] continuous use temperature range
  • No cooling required. Increase your productivity by reducing duty cycling
  • High sensitivity with integrated wedges across the temperature range
  • Stable signal for reliability and repeatability – no duty cycling means no drift from thermal gradients in the wedges
  • Short approach to beam exit to get closer to weld caps
  • Enhanced wear resistance for the most extreme environments and applications
  • Compatible with commercial scanners and crawlers


  • Make weld inspections on hot assets, on-stream, without the need to shutdown or isolate
  • Make effective weld root corrosion assessments rapidly at high-temperature
  • Detect and size cracks or defects in welds or parent material on-stream
  • Screen for HTHA in-service
  • TOFD carries the highest POD for NDT methods



HS582i Case Study - Enhanced service life
Enhanced service life with high-temperature corrosion surveys

Longer lasting, higher availability of UT tools for on-stream, high-temperature corrosion surveys to maximise plant availability, productivity and safety.

corrosion survey
In-service corrosion survey of chemical refinery

In-service, high-temperature corrosion surveying to maximise productivity, safety & plant availability

On-stream, high-temperature corrosion mapping

Combined with magnetic crawlers and scanners, visualisation of assets can be produced on-stream

On-stream corrosion inspection survey using a high temperature UT probe

On-stream, high-temperature corrosion surveying with HS582i.

In-service High Temperature UT Inspection Survey by MISTRAS at a U.S. Oil Refinery

Ultrasonic Testing (UT) measurements of on-stream process pipework and equipment at high temperatures.


Parameter ValueUnit
Surface temperature range*-55 to +350 / [-67 to +667]°C / [ °F]
Refracted Beam50, 60 and 70, longitudinal at 200 °C / 392 °F *degrees
WedgesEngineering polymer in steel, integrated
Profiled on request
mm / [in]
Connector typeLemo 00-
Pivot pins5 mm pins as standard **-
Couplant nozzlesto fit 4 - 4.5 mm tubes-
RuggedisationDesigned to meet IP 65
Stainless steel construction
Acoustic characteristics certificate of conformity to ISO 22232-2 supplied with each unit
Transducer centre frequency5.0 at 50 & 60 deg wedge angle
6.0 at 70 deg wedge angle
Active element diameter6.0mm
Beam exit distance from edge1.5mm

Compatible with UT flaw detectors and scanners
*Refracted angle temperature dependence on steel
**Other variations available via special request
For couplant, cables accessories and other specifications please contact our sales team


Parameter ValueUnit
Minimum wall thickness6mm


HS582i FAQ

If you have any further questions or require technical support, please contact Ionix at