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High-temperature Ultrasonic Couplant

High-temperature Ultrasonic Couplant

Couplant EchoFLOW Echo 3 HT Echo 6 HT Echo 8 HT
Operating Range -40° to 150°F / -40° to 65°C -30° to 350°F / -34 to 177°C -40° to 675°F / -40 to 357°C -50° to 800°F / -45 to 425°C
Typical Pumpable
-40° to 150°F / -40° to 65°C 35° to 350 °F / 2 to 177°C 0° to 675°F / -18 to 357°C GR 1: 30° to 800°F
GR 4: 50° to 800°F
Viscosity at
68°F / 20°C
25 cps 110 cps 90 cps GR 1: 150 cps*
Gr 4: 400 cps
Viscosity at
170 cps 2100 cps 200 cps GR 1: 900 cps
GR 4: 4200 cps
Auto-Ignition Temp. N/A 628°F / 331°C 789°F / 421 °C 850°F / 454 °C
Temperature at
which no detectable
vaporization at 5
N/A 280°F / 138°C 675°F / 357°C 800°F / 427°C
Key Attributes -Easily pumped in extreme
cold environment
-Environmentally safe, Alaskan
Tundra approved
-Water-soluble. No need to
-Water-soluble. No need to
-Least expensive
intermediate temperature
-Low cost silicone-based fluid
-Replaces peanut, canola &
mineral oil
-No sticky film, varnish or
-Reduced risk of under
insulation cracking
-Highest temperature AUT
-Little or no residue
-Two viscosities

Echo Flow Fluid

EchoFLOW is an AUT fluid couplant that is easy to pump in cold environments and will not boil or evaporate on hot parts up to 240°F / 115°C. The increased acoustic impedance reduces surface noise on rough surfaces and highly attenuating materials and enhances ultrasound transmission.

EchoFLOW is non-toxic and safe for use in critical environments, such as Alaska’s Arctic Tundra.

  • High acoustic impedance
  • Low viscosity fluid, pumpable at -40°F/C
  • Pasteurized for product purity
  • Will not harden on equipment
  • Compatible with plastics
  • Approved for use over the Alaskan Tundra
  • Non-toxic, non-irritating
  • Contains no heavy metals, harsh surfactants, glycol ethers, nitrites, silicones, dyes or fragrances.

Echo 3 HT

When water won’t work, Echo 3 HT is the next step. For temperatures up to 350˚F (177˚C), Echo 3 HT is water soluble, leaves no residue and is compatible with a broad range of materials.

  • Broad operating range -30 °F to 350°F (-34°C to 177°C)
  • Water soluble: easier to remove than most fluid ultrasonic couplants
  • No “oil slick” when used where couplant may drip into a body of water.
  • Lowest viscosity fluid that remains pumpable down to 35°F / 2°C
  • Low toxicity
  • Compatible with a broad range of materials including most metals, plastics and composites
  • Good Surface wetting due to low surface tension and solvent properties.
  • Slow Drying at ambient temperatures

Contains no glycerin which can interfere with subsequent penetrant inspection.

Environment and operator friendly – no formaldehydes, nitrates, nitrites or glycol ethers.

Minimal residue

Removal: Wipe with wet or dry paper or cloth rag or water wash.

Echo 6 HT

Echo 6 HT™ is a low-cost silicone based high-temperature, slow-drying, fluid ultrasonic couplant replacing plant based oils (peanut and canola) and mineral oils. Echo 6HT has no residue and is less subject to under insulation cracking (which leads to a lower auto-ignition temperature).

  • Unlike plant-based oils, Echo 6 HT won’t form a film or varnish nor will it gum up bearings or equipment. Echo 6 HT serves as a long-term lubricant for mechanical AUT equipment.
  • Echo 6 HT is low in viscosity and maintains a stable viscosity across a broad operating range.
  • Echo 6 HT has low toxicity and is essentially non-irritating.
  • Echo 6 HT provides excellent corrosion inhibition on ferrous metals and is compatible with all metals and most plastics.

Echo 8 HT

Echo 8 HT™ is a line of high temperature, slow drying fluid ultrasonic fluids with an excellent safety profile and is compatible with all metals and most plastics.

Echo 8 HT™ High temperature ultrasonic coupling fluids are available in four viscosities; Grades 1, 4 and 10.  Performance of a broad range of AUT and MUT ultrasonic flaw and thickness gaging applications from -50°F to 800°F (-45°C to 425°C) is possible with these four grades.

Grade 1 is the lowest viscosity fluid (100 cST) for long or small diameter lines and quick spreading.

Grade 4 is Echo’s standard viscosity fluid (400 cST) and is usually a good compromise between pump ability and run-off at the transducer.

Grade 10 is a very thick fluid (5,000 cST – honey like) for MUT.  It spreads easily over large hot surfaces, stays in place and leaves minimal, if any residue.

All grades of Echo 8 HT provide excellent corrosion inhibition on ferrous metals, leave minimal residue and are compatible with all metals and most plastics.

Echo 8 HT has low toxicity and is essentially non-irritating