Fluid Couplants for AUT Inspections in the Winter
Three Types of AUT Fluid Couplants
With winter approaching, many of you will be performing AUT inspections on high temperature parts in a cold environment. Echo has three types of AUT fluid couplants for your AUT needs.
Most liquids increase in viscosity as the temperature decreases. It is important to select a fluid that will work with the diameter and length of tubing and the pump you are using as temperatures drop below freezing.
Each of Echo’s AUT fluid couplants have unique properties in cold weather.
EchoFlow™: Developed for AUT inspection in Alaska, the formulation of EchoFlow is environmentally safe and approved for use on the Tundra. The operating range for EchoFlow goes down to -40°F/C, with the viscosity increasing from 25 cps at ambient (68°F) to 170 cps at 0°F. EchoFlow can be applied to equipment as hot as 150°F (65°C). EchoFlow is water-soluble with no need for removal in many applications.
Echo 3HT™: For warmer pipes, Echo 3HT covers a range of -30 to 350°F (-34 to 177°C). The viscosity of Echo 3HT at ambient temperatures is 110 cps and increases to 2100 cps at 0°F. While this is still pumpable, larger diameter tubing and shorter lines are necessary. Echo 3HT is the least expensive intermediate temperature AUT fluid.
Echo 6HT™ is an excellent replacement for plant oils (peanut and canola), especially in colder temperatures. Echo 6HT has an operating range of -40 to 675°F (-40 to 357°C) and an ambient viscosity of 90 cps. At 0°F the viscosity increases to 200 cps. Echo 6HT is the lowest cost silicone-based AUT fluid, does not leave a sticky film or varnish, and does not smoke.
Echo 8HT™ is the broadest temperature AUT Fluid with an operating range of -50 to 800°F (-45 to 425°C). Grade 1 is the best choice for cold temperatures. Ambient viscosity of Grade 1 is 150 cps, increasing to 400 cps at 0°F. The viscosity of Grade 4 increases to 4200 at 0°F which is not considered pumpable. Echo 8HT leaves little to no residue.
As an ISO 9001:2015 certified company, Echo Ultrasonics AUT fluids are always shipped with the documentation you need:
- Certificate of Analysis (C of A)
- Safety Data Sheet (SDS)
- Product label listing the operating range and auto-ignition temperature
Not sure which fluid is best for your application? Call Echo’s office and speak to one of our couplant experts: 360-671-9121 or email us at sales@echoultrasonics.com.