Cygnus Underwater

Ultrasonic Thickness Gauge

Cygnus' original diver-held subsea multiple-echo ultrasonic thickness gauge, designed for use by divers undertaking subsea maintenance and surveys 3 decades ago… and today it is still an industry standard.

The Cygnus Underwater is the original diver-held subsea Multiple-Echo ultrasonic thickness gauge. It was designed for use by divers undertaking subsea maintenance and surveys 3 decades ago… and today it is still an industry standard. Ideal for inspecting underwater structures, e.g. bridges, tanks, canal locks, subsea pipelines and equipment, UWILD or IWS class surveys.

Key Feature:

  • Multiple-Echo mode for accurate, through-coat measurements as specified by Classification Societies
  • Deep Coat mode ignores coatings up to 20mm thick (upon request)
  • Heavy duty sealed unit with double ‘O’ ring protection
  • Rugged, durable, shock-proof construction
  • Easy and stable calibration – no zero adjustment
  • Echo strength indicator to aid measurement
  • Two rechargeable battery packs with charger
  • Auto-Probe Recognition (APR)
  • Topside Repeater options: Option A – Palm-held Topside Repeater (TSR); Option B – CygLink software (Windows based) for data logging and remote display.
Materials Velocities between 2,000 and 7,000 m/s (0.0800 to 0.2780 in/us) – covers virtually all common engineering materials
Measurement Range in Steel 1 – 250 mm (0.040 – 10 inch) depending on selected probe and configuration, material and temperature
Accuracy ±0.1 mm or 0.1% of thickness measurement, whichever is greatest, when calibrated in accordance with Cygnus Instruments calibration procedure
Resolution 0.1 or 0.05 mm (selectable) (0.005 or 0.002 inch)
Probe Options Single crystal probes
Power 2 x rechargeable NiMH battery packs
Battery Life 2 x 20 hours continuous measuring (with fully charged battery packs)
Display Large, bright LED display
Size 238 x 85 mm (9.4 x 3.4 inch) (inc. battery pack and probe head)
Weight 977 g (35 oz) (inc. batteries)
Operating Temp. -10°C to +50°C (14°F to 122°F)
Environmental Protection IP68 continuous 300 m (984 ft) rating
Standards Designed for EN 15317
Compliance CE, UKCA, RoHS
Weight 5 kg

Cygnus Underwater Gauge Standard Kit WITHOUT PROBE

To compliment our ultrasonic thickness gauges we offer a range of ultrasonic probes. The performance of any ultrasonic thickness gauge relies heavily on the probe and its suitability to the material being measured. Therefore, selecting the right probe is vital. All Cygnus SINGLE CRYSTAL probes are made from stainless steel and include replaceable membranes for long life, requiring no zeroing and have a high linear accuracy.

Topside Repeater Remote Display Unit

The Cygnus Topside Repeater is a remote display unit connected to the gauge with an umbilical cable. It displays the thickness measurements at the surface in real-time during the survey.

Topside Repeater options: (A) Palm-held Topside Repeater (TSR) or; (B) CygLink software (Windows based) for data logging and remote display.

CygLink Computer Software

CygLink is a Windows® based application used to display, log and transfer thickness measurements at the surface. The software can generate PDF reports and export to CSV files, allowing for after-theevent analysis of logged measurements. Designed for Windows 7 and above.

The latest version of CygLink software is available to download from ‘Software Downloads’.

3 reviews for Cygnus Underwater


Jan 09, 2015 1:12 PM

I received the Cygnus 1 in 1987 and used it continuously for 10 years on submerged pipelines, without any problems. After that period it was mainly used for ship board survey inspections of hull thickness testing which is still in use today with the same set of batteries. I cannot praise this piece of equipment enough as it has given unbeatable service in extremely hostile environments without failing at any time. I would recommend this unit to anyone looking for a reliable ultrasonic thickness testing unit.

Anders P.

Jul 01, 2019 1:11 PM

Since my purchase of the Cygnus 1 Underwater gauge in 2005, I have had no problem with the gauge, and it’s still going strong after 14 years of use by divers, completing many underwater inspections across countries in Africa and Europe. There were times where it wasn’t easy to get readings on odd surfaces or through small marine growth, but we succeeded eventually.

Santosh G.

Apr 23, 2020 1:11 PM

There are many in the industry who have been using Cygnus meters for more than 20 years. I myself have used their underwater thickness gauge along with regular and Intrinsically Safe UT meters from the early stages of my career – and that goes back to more than 25 years for sure. TechCorr, a global leader of inspection services, uses Cygnus Gauges for pipelines, tanks and vessel inspections. Our operators particularly love Cygnus – as readings come quick and accurate.

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