Couplant Selection Chart

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All Echo Ultrasonics® couplants have been formulated with operator safety and environmental regulations as a priority.

Ambient Temperature Couplant Comparison

Couplant Key Benefits Viscosity Temperature
Range
Corrosion
Characteristic

ambient-temperature-ultrasonic-couplant-comparison

 

SuperSoniX™

  • Expanded Ambient Temperature
  • Gel couplant, not stringy or sticky
  • Viscosity remains in place for overhead and vertical surfaces
  • Broad operating range
  • Slow drying
  • Water-soluble
  • Improved stability against corrosion salts
Medium and
High
-10 to 220°F
-23° to 104°C
Very good

Signal™

  • Improves signal to noise ratio on rough surfaces such as castings, rough bar stock and fiberglass
  • Highest acoustic impedance of any water-based ultrasonic couplant
  • Slow drying
  • Water-soluble
Medium -18° to 224°F
-28° to 107°C
Very good

UltraSoniX™

  • Glycerin-free, in accordance with FAA Advisory Circular AC 25-29
  • Slow drying, Fast wetting
  • Water soluble
Medium 10° to 220°F
-12° to 104°C
Very good
Meets ASTM F519

EchoPure™

  • Couplant of choice for Phased Array Manual UT Inspection (PAMUT). Eliminates dry spots under the wedge and resulting element drop out. Improves defect reproducibility.
  • Complies with P91 steel inspection requirement for a water-free couplant.
  • Broadest temperature range for water-soluble couplants
  • No couplant build up which can result in false indications.
  • Very slow drying and salt stable
  • Overhead / vertical application
  • Excellent transducer lubrication
High
Medium
Low
Fluid
-60° to 350°F
-51° to 176°C
Very good
Meets ASTM F519

SoniX™

  • Salt stable (boiler and corrosion salts, etc.)
  • Strong lubricious coupling film
  • Fast Wetting
  • Glycerin-free
  • Water soluble, cellulose based
Medium 18° to 120°F
-8° to 50°C
Very good
Meets ASTM F519

Glycerin

  • GE approved for the inspection of CFM56-7B engine fan blades in accordance with service buletin SB72-1033
  • Packaged from UPS Glycerin, 99+%
  • Will not harden on equipment
  • Pumpable fluid
  • Compatible with most plastics
Fluid 65° to 500°F
18° to 260°C
Can be corrosive to carbon steel and aluminum. No corrosion effects in most plastics, fiberglass, or composites.

Powder Couplant Comparison

Couplant Key Benefits Viscosity Temperature
Range
Corrosion
Characteristic
powder-ultrasonic-couplant

EchoMix®
Single

  • ONE PART powder
  • Easily mixed in water
  • Salt resistant
  • No formaldehyde
  • Compact for shipping and storage
  • Water soluble
  • Operating range can be extended with propylene glycol antifreeze
Medium gel
Adjustable
low to high
32° to 120°F
0° to 50°C
Mild, short term
ferrous corrosion inhibition

Speciality Couplant Comparison

Couplant Key Benefits Viscosity Temperature
Range
Corrosion
Characteristic
speciality-industrial-couplant

Forever Wedge Couplant™

  • High viscosity fluid for phased array and angle beam wedge attachment and for coupling delay lines
  • Won’t dry, run, leach or dissolve with water or couplants
  • Eliminates the need to replace wedge couplant during inspections
Fluid -50 to 700°F
-45° to 371°C
N/A

Echo Shear Wave Couplant™

  • Transmit normal incidence shear wave
  • Water soluble, easily removed with water
  • Low toxicity, non-irritating
Paste 40 to 90°F
4° to 32°C
N/A

Echo Z+™

  • High acoustic impedance
  • Decreases surface noise
  • Ideal for rough surfaces and concrete
  • Strong ferrous corrosion inhibition
Fluid,
Low,
Medium,
High,
Very High
0 to 200°F
-18° to 93°C
Strong ferrous corrosion inhibition

Echo 8ZH™

  • For flow metering and long term monitoring at elevated temperatures
  • Enhanced acoustic impedance
  • Reduces acoustic noise from rough surface
Paste Short term:
-45 to 750°F
Long term:
-45 to 400°F
Strong ferrous corrosion inhibition

High Temperature Couplant Comparison

Couplant Key Benefits Viscosity Temperature
Range
Corrosion
Characteristic
high-temperature-ultrasonic-couplant-comparison

VersaSonic®

  • Broad operating range – subzero to 700°F
  • Best performing UT couplant between 300 and 700°F
  • Fast Response, no wait time
  • Low smoke / Low toxicity / No char residue
  • Does not contain peanut oil
Medium and High Viscosity Gel -10° to 700°F
-23° to 371°C
Best long-term corrosion protection. Meets ASTM F519

HiTempco+™

  • Less smoke than VersaSonic
  • No residue or varnish
  • Fast response, no wait time
  • Excellent corrosion inhibition
  • Non-toxic, non-irritating
Paste -50° to 850°F
-45° to 455°C
Excellent corrosion inhibition

AeroSoniX™

  • High Temperature Couplant for Drones
  • Pumps like a fluid, stays in place like a gel
  • Optimal viscosity for drone inspections
Low Viscosity Gel -50° to 775°F
-45° to 412°C
Excellent corrosion inhibition

EchoTherm™

  • Ultra-high temperature couplant
  • Stable reading once polymer melts (a few seconds). Best on difficult measurements such as heavy corrosion, curved surface and small pipe
  • Will smoke at 750°F
  • Leaves plastic residue and should be wiped off transducer after use
Paste 200° to 1000°F
93° to 538°C
N/A

EchoTherm Extreme™

  • Highest performance extreme temperature couplant
  • Fast Response, no wait time
  • No plastic polymer / char residue
  • Broadest operating range
  • Low smoke
Paste -40° to 1250°F
-40 to 675°C
Meets ASTM F519

Fluid Couplant Comparison

Couplant Key Benefits Viscosity Temperature
Range
Corrosion
Characteristic
pumpable-fluid-ultrasonic-couplant

EchoFLOW™

  • Easily pumped in extreme cold environment
  • Environmentally safe, approved for use on the Alaskan Tundra
  • Water-soluble.
Fluid -40° to 150°F
-40 to 65°C
N/A

Echo 3HT™

  • Water-soluble. No need to remove
  • Least expensive intermediate temperature fluid
Fluid -30° to 350°F
-34 to 177°C
Similar to water

Echo 6 HT™

  • Low-cost silicone-based fluid
  • Replacement for peanut, canola and mineral oils
  • Low in viscosity, which is maintained over a broad operating range.
  • No sticky film, varnish or smoke
Fluid -40° to 675°F
-40° to 357°C
Excellent

Echo 8 HT™

  • Broadest operating range
  • Three Viscosities: thin to very thick liquid for AUT and MUT
  • Minimal smoke
  • Excellent lubricant
  • Low toxicity / Non-irritating
  • Auto Ignition is 850°F/454°C
Fluid -50° to 800°F
-45° to 425°C
Excellent

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