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DFX6, Ultrasonic Flaw Detectors

DFX6 Ultrasonic Flaw Detector

The DFX6 Ultrasonic Flaw Detector is no longer available and has been replaced by DFX8.
Click here to see the DFX8.

Made in the USAThe DFX series ultrasonic flaw detectors are full featured digital scopes designed to handle the simplest to the most difficult applications. Whether the application requires high penetration for materials that are difficult to measure, or high resolution for precision aerospace parts, the DFX series flaw detectors are equipped with the necessary features to do the job. They can go where you go, to do the work you do, saving you time and money, making your inspections fast and accurate.


  • Transflective Color TFT Display
  • Broad & Narrow Band Amplifier
  • Square Wave Pulser (Active Edge)
  • Extruded Aluminium Case (IP65)
  • Digital Thickness Display
  • Automatic Calibration
  • PC/Video/Analog Outputs
  • Long Battery Life (Li-ion pack)
  • Large Memory Capacity
  • Curved Surface Correction
  • Alphanumeric Notes
  • Trig function
  • Help feature


9.25 x 7.13 x 4.0 in (235 x 181 x 102mm)
7.5lbs. (3,4Kgs) with Li-Ion cells.
Extruded Aluminum.
transflective TFT Color. Display area: 4.39” x 3.29” (111.4 x 83.5mm) 320 x 240 pixels. A-Scan area: 255 x 200 pixels (315 x 200 expanded), 8 color options and variable brightness.
Operating –10 to +55°C or 14 to 131°F –20 to +70°C or –4 to 158°F (survivable) Storage –40 to +75°C or –40 to 167°F
Meets IP65 requirements.
English (in), Metric (mm), or Time (µs).
Probe Zero
0–999.999 µs.
615 & 625 0.0393 to 0.3937 in/µs (1000–9999m/s). 635 & 638 0.0100 in/µs (256 to 16000 m/s.
Test Range
615 & 625 0 - 0.2in (5mm) up to 0 - 400in (10,000mm) at steel velocity. Variable in sequence, 0.4in or 0.04in (10mm or 1mm). 635 & 638 0 - 0.05in (1mm) up to 0 - 800in (20,000mm) at steel velocity. Variable in 1, 2, 5 sequence or continuously in 0.05in (1mm) increments. Also from 1 to 5000(µs).
Test Modes
Pulse-echo and transmit/receive.
615 & 625 Start & Width adjustable over full range. Amplitude 0 -100%, 0.5% steps. Visual & audible alarms. Single gate positive trigger, and two gates positive and negative triggering. Gate 2 has selectable 0.6 second delay on alarm. 635 & 638 Two fully independent gates with positive and negative triggering for each gate.
Gate Expansion
635 & 638 Expands range to width of Gate 1.
Gate Monitor Delay
635 & 638 Selectable 0.6 sec delay on gate 2 negative monitor.
Measurement Modes
Signal Monitor
635 & 638.
Depth and amplitude of signal in gate
Echo Echo
Echo-Echo distance, automatic gate 2 position.
Gate to Gate
625 Echo-Echo , manual gate 2 position. 635 & 638 independent gates.
Trigonometric display of beam path, depth and surface distance. Calculation of skip depth and curve surface compensation, X-offset for transducer.
Holds minimum thickness in depth mode.
System Linearity
Vertical = 1% Full Screen Height (FSH) Amplifier Accuracy ±0.1%dB. Horizontal ±0.4% Full Screen Width (FSW).
Pulser Voltage
615 & 625 200 volt peak amplitude, rise/fall time < 10ns into 50ohm. 635 & 638 100V - 350V (450V 638 ) square wave pulser. Pulse width from spike to 2000ns duration - rise/fall times < 5ns into 50 ohms.
Pulser Width
615 fixed at 100ns. 625 30-250ns linked to filter band. 635 & 638 Adjustable in 2% of nominal width, minimum 1ns maximum 40ns.
Unique active pulse control for enhanced near surface resolution and signal response. Replaces traditional damping control.
615 fixed at 100ns. 625 30-250ns linked to filter band. 635 & 638 Adjustable in 2% of nominal width, minimum 1ns maximum 40ns.
Screen Update Rate
50 or 60Hz
Full wave, positive or negative half wave and unrectified RF.
615 & 625 0 - 400 in (10,000mm) 635 & 638 0 - 800in (20,000mm) at steel velocity in 0.02 steps (0.05mm).
0 to 110dB. Adjustable in 0.5, 2, 6, 14 and 20dB steps
Frequency Bands
615 4Broadband 1 - 10 MHz (-6dB). 625 4 Narrow Bands centered at 1MHz, 2MHz, 5MHz, & broadband 1.5–15MHz. 635 & 638 6 narrow bands centered at 0.5, 1, 2.25, 5, 10 & 15 MHz. Broad band at 2 to 22 MHz (-6dB) and 1 to 35 MHz (-20dB).
Vertical Linearity
1% full screen height.
Amplifier Linearity
+/- 0.1 dB.
Horizontal Linearity
+/- 0.4% full screen width (FSW).
615 & 625 50% suppressive reject. LED warning when selected. 635 & 638 80% linear reject.
Thickness Logging
Storage for 8000 readings stored in Block/Location/Number coding or alpha-numeric pre-programmed work sheets. Transferable to Excel using optional PC software.
Panel Memory
100 storage locations for calibration settings.
A-Scan Memory
800 waveforms.
Wave Smoothing
Produces a smooth signal envelope.
Automatic Gain Control sets selected echo to a user defined level (10 - 90%).
Up to 10 points may be entered and used to digitally draw a DAC curve. Reference -2, -6, -10, -12, -14 dB curves can be selected for JIS, ASME and EN1714 codes.
Automatic defect sizing in accordance with AWS D1.1 Structural Welding Code
Automatic defect sizing in accordance with API 5UE.
Automatic defect sizing using probe data. 10 probe data sets can be stored.
625, 635 & 638 Time corrected gain. 40 dB dynamic range, 30 dB per microsecond, up to 10 points for curve definition.
Provides Automatic calibration with two echoes.
Reference Waveform
Recalled waveform can be shown in a different color to live waveform for direct comparision.
Display Freeze
Hold current waveform on screen.
Peak Memory
For echodynamic pattern determination.
Online Help
Instant operator guidance on operation accessed from direct key.
Language Support
Six user selectable languages from: English, German, French, Spanish, Dutch, Italian, Russian, Polish, Czech, Finnish & Hungarian. Others available on request.
Lithium Ion battery pack 14.4V, 5.0 Amp hrs. Minimum 11 hours use, typical 15 hours, indication of battery charge. Recharge time 4 hours.
100 - 240 VAC, 50 - 60Hz.
USB Connection
For connection to PC, keyboard and printer.
Serial Interface, composite video (NTSC & PAL), analog output for amplitude and distance updated at PRF rate. Transmitter sync output.
Transducer Connectors
available with BNC or LEMO 1 connectors (factory option).
2 year limited
Additional 638 Features
Interface trigger
Interface gate locks to surface echo and eliminates water path variation.
High Power Pulser
450 volt boost.

Complete Kit

The DFX6 is supplied as a complete kit including:
- DFX6 Flaw Detector,
- Lithium Ion Battery,
- Battery Charger CH-700,
- Canvas instrument case,
- Clear Screen,
- Operating manual,
- Calibration certificate,


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