Supply in Kazakhstan
KEG TRK supplies ultrasonic diagnostics solutions (SDT Ultrasound Solutions) across Kazakhstan: Almaty, Astana, Karaganda, Ust-Kamenogorsk, Aktobe and other regions. Official warranty, monitoring system design, installation, commissioning and personnel training.
Mining equipment
Key features
Applications and resources
Industry solutions, landing pages and articles on SDT FLEX.US - Flexible Ultrasound Leak Detector (Discontinued)
Where it is used
Typical tasks
- Compressed-air and gas leak detection in hard-to-reach spots
- Tightness testing of vehicle cabs, cockpits and equipment enclosures
- Inspection inside cabinets and through narrow access holes
- Pinpointing a leak by tracking increasing signal volume
Overview
The SDT FLEX.US was a stand-alone ultrasound leak detector from the SDT170 era, sold by SDT International under its own product code, FUFLUS-01. Unlike a plug-in sensor accessory, FLEX.US was a separate instrument in its own housing: a flexible ultrasound sensor at the end of a metal tube, a built-in amplifier, a heterodyne converter and a headphone output, with no connection to a base detector required. Its sensing element built on SDT's popular "flexible sensor" design, but unlike that sensor it wasn't an optional attachment for the SDT170 — it switched on and ran independently, powered by its own batteries.
This model has been discontinued. There is no direct, identically named successor in the current SDT lineup. Today, the "detector + transmitter" combination for tightness testing is covered by TIGHTChecker — a modern detector-plus-ultrasound-transmitter kit for the same purpose (testing the tightness of tanks, cabs and seals), built on the digital Checker Range platform with a real-time histogram display.
Key features
Self-contained design
- Everything in one housing — the piezoelectric sensor, amplifier, heterodyne converter and headphone connector are all built into a single shock-resistant polystyrene housing
- 400 mm flexible probe — a metal tube that bends and twists to reach welded seams, components behind panels and the inside of cabinets
- Focusing tip — a tube mounted over the sensor improves detection accuracy and rejects competing background noise
Controls
- One button — a single sealed rubberized switch handles power and sensitivity
- 7 gain levels — from 20 to 80 dB
- Indicator — a red LED confirms the unit is powered on
Tightness testing of enclosed volumes
- Paired with the optional SDT E200mW transmitter, FLEX.US tests the tightness of vehicle cabs, cockpits and equipment enclosures: the transmitter is placed inside the volume, FLEX.US scans the seams from outside, and rising signal volume marks a leaking section
Technical specifications
| Parameter | Description |
|---|---|
| Type | Stand-alone ultrasound leak detector |
| Control | One button (on/off + volume), silicone-sealed |
| Amplification | 7 levels: 20, 30, 40, 50, 60, 70, 80 dB |
| Ultrasound sensor | Open type, 16 mm (internal) / 19 mm (external), 40 kHz centre frequency |
| Detected frequencies | 38.4 kHz ± 2 kHz (-3 dB) |
| Audio output | 6.35 mm stereo jack, supplied headset only |
| Power | 2 x AA alkaline (rechargeable cells accepted) |
| Runtime | ≈20 hours |
| Housing | Shock-resistant polystyrene |
| Body dimensions | 170 × 42 × 31 mm |
| Flexible probe length | 400 mm |
| Weight | 412 g with batteries |
| Operating temperature | -10°C to +50°C |
Why the model was discontinued
FLEX.US belonged to the SDT170 generation of instruments — separate, single-task detectors with no memory, no digital readout and no data transfer. As the lineup moved to the digital Checker Range platform with real-time histogram detectors, SDT stopped producing stand-alone one-button detectors in favour of "general-purpose detector + dedicated sensor/transmitter" combinations — which is why FLEX.US's job is now handled by TIGHTChecker.
What to choose instead of FLEX.US
- TIGHTChecker — a detector-plus-transmitter kit for testing the tightness of tanks, cabs and seals, the direct functional equivalent of FLEX.US + SDT E200mW on a modern platform
- ULTRAChecker — a general-purpose detector for air and gas leaks, if the task isn't limited to enclosed-volume tightness testing
- SDT170 — for reference: the base detector of the same era that FLEX.US could connect to as one of its compatible flexible sensors
Support for this discontinued model
- Standard AA batteries and a common 6.35 mm jack are enough to keep previously purchased FLEX.US units in service
- Repair of the piezoelectric sensor and housing is available through SDT's authorized service centres
- For new purchases, migrating to TIGHTChecker is recommended
Technical specifications
| Frequency range | 38.4 kHz ± 2 kHz, 40 kHz centre frequency |
| Sensor | Open piezoelectric sensor, 16 mm (internal) / 19 mm (external) |
| Probe | 400 mm flexible tube |
| Battery | 2 x AA (alkaline or rechargeable), ~20 hours |
| Temperature | -10°C to +50°C |
| Weight | 412 g with batteries |
| Output | 6.35 mm stereo jack for the supplied headset |
Applications
Manufacturer
SDT Ultrasound Solutions
Stand-alone ultrasound leak detector with a flexible probe from the SDT170 era, now discontinued. The closest current equivalent is TIGHTChecker
Key specifications
- Frequency range
- 38.4 kHz ± 2 kHz, 40 kHz centre frequency
- Sensor
- Open piezoelectric sensor, 16 mm (internal) / 19 mm (external)
- Probe
- 400 mm flexible tube
- Battery
- 2 x AA (alkaline or rechargeable), ~20 hours
- Temperature
- -10°C to +50°C
Official supplier in Kazakhstan
Related products
SDT170 - Ultrasound Detector (Discontinued)
Multifunctional ultrasound detector from a previous SDT generation, now discontinued. Current replacement — SDT270
- Tunable ultrasonic frequency
- LCD: bar graph + digital readout, borosilicate glass protection
TIGHTChecker - Tightness Testing
Detector plus ultrasonic transmitter kit for tightness testing of vessels, seals and enclosures
- Tightness testing kit
- Tightness testing of seals, vessels and enclosures
ULTRAChecker - Universal Ultrasound Detector
The universal Checker Range detector: one model for mechanical, leak, electrical, and valve inspections, no training required
- Universal Checker Range detector
- Mechanical, leaks, electrical, valves
Need advice?
Our specialists will help you choose the optimal SDT FLEX.US - Flexible Ultrasound Leak Detector (Discontinued) configuration for your equipment.
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