How To Use Ultrasonic Thickness Gauges

If you are looking to get the most out of a Cygnus Instruments ultrasonic thickness measuring gauge, then you will need to know how to access and utilise the features that are included with each device. Every device is different, because they are designed for a different degree of professional user. The industries that require a more simplistic design are better off using a Cygnus 1 Intrinsically Safe, rather than a Cygnus 6+ Pro. This is because the Cygnus 6+ Pro is designed for a multitude of different scenarios, which a flexible and experienced user will be able to make use of.

Which measurement method should I use?

How to use ultrasonic thickness gauges

This is one of the most important questions you can ask yourself. If you are trying to get the measurement for a particular surface thickness, but the gauge you are using does not have the correct probe attached or it is set up incorrectly, then your measurement will obviously be the same.So, what are the various measuring methods? Well, there are three different ultrasonic pulse and detection variations. We will start with the simplest ultrasonic measuring methods first.

Single Echo

This method is perhaps the simplest. However, it is not recommended for use when you are trying to ascertain the depth of the metal by itself. This method cannot account for the depth of a coating, such as paint. This means you can accurately gauge the depth of a metal or engineering material that is not covered by a coating of any kind. If you measure the coating and the metal, the thickness gauge will give you a reading for both of the thicknesses combined. This type of measurement method uses a double crystal probe.

Echo to Echo

Similar to the single echo method, this ultrasonic thickness measurement mode uses a double crystal probe. Unlike the single echo method though, it can ignore coatings up to a maximum coating depth of 1mm. This is ideal for non-destructive testing on materials that have a thin coat of protective paint, sealer, dirt, and others. The use of two consecutive echo signals is what allows your ingenious Cygnus device to differentiate between the coating and the material, and thus eliminate the coating from the measurement.

Multiple Echo

Multiple echo is the most widely used variation of the measuring modes available. Pioneered by our engineers here at Cygnus Instruments, it uses multiple sound pulses (hence the name) to ignore coatings up to 20mm thick. This particular method uses single crystal probes, unlike the other two methods.

Mark V Features

The latest range of our instruments, the Mark V collection, have a host of features and refinements that you will find useful at any end of the spectrum, from simple tasks to complex professional data logging and analysis. For a device which uses a twin crystal probe, you will need to know how to zero the probe before accurate measurements can be obtained.For those who are using a Cygnus 4+, you will be able to get the most out of it after it has been properly calibrated for NDT ultrasonic tests. This will ensure accuracy to a degree of 0.1mm or 0.1%, whichever is greater. You can also use the two-point calibration method to get the Cygnus 4+ ready for usage. Available on the 6+ Pro, as well as the 4+, you can set maximum limit alerts and data logging comments for increased functionality, to give you a truly bespoke experience when using our devices.You will find our YouTube channel full of useful videos which can guide you through the various functions of a number of devices, including the Cygnus DIVE, reviewing, saving, and setting up B-Scans for the Cygnus 6+ Pro, and many more. If you have any questions about our devices, or can’t find the information you need in our YouTube tutorials or resources section, contact us at Cygnus Instruments. You can speak to a member of our expert team on +44 (0)1305 265 533 or email us at