How to Survey Steam Traps with SDT Ultrasound: Step-by-Step Method
Practical steam trap survey method from SDT: upstream/downstream readings, temperature for failed closed, blow-through signatures, how to read the cycle. Field photos with SDT340.
Basis. SDT “Conducting Steam Trap Surveys” plus SDT340 / TrapChecker practice.
Why method beats “just listen”
Traps fail open (live steam loss) or closed (water hammer, cold consumers). Body temperature alone cannot separate a healthy hot trap from blow-through — you need flow character from contact ultrasound.
Steps
- Route prep — tag, type, pressure; load routes in SDT340 / TrapChecker.
- Upstream reading — confirm system noise/steam.
- Failed closed check — spot radiometer: hot supply + cold body → often stuck closed.
- Trap / downstream reading — cyclic = OK; continuous roar = blow-through; silence = closed/no flow.
- Report — repair high-pressure blow-through first.
See the 400+ trap campus case. KEG TRK — request training.
Equipment in this article
KEG TRK quotes prices and delivery times to Kazakhstan on request. We will prepare a commercial offer for your application.
SDT340 - Advanced Ultrasound Detector
The most advanced ultrasound detector for collecting, analysing and trending data
TRAPChecker - Steam Trap Testing
A specialised detector for testing steam-trap performance
Also in this article: ULTRAChecker - Universal Ultrasound Detector
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