1. Introduction
The GOYOJO GUF750 is an industrial-grade ultrasonic flaw detector designed for precise, stable, and efficient non-destructive testing (NDT). This portable device is ideal for detecting flaws in welds, pipelines, and various structural materials, offering exceptional sensitivity and accuracy. Equipped with a 5.0-inch HD IPS touchscreen, it provides an intuitive interface and a range of advanced functions to enhance diagnostic capabilities in demanding environments.
Figure 1: GOYOJO GUF750 Ultrasonic Flaw Detector in operation with a probe.
2. Product Overview
The GUF750 integrates multiple detection modes, DAC/AVG quantitative analysis, and complies with international flaw detection standards. Its robust design and long-lasting battery make it suitable for extensive field use.
Key Features:
- High Sensitivity: Frequency bandwidth of 0.1–20 MHz and a 120 dB gain range.
- Advanced Analysis: DAC/AVG quantitative analysis for accurate flaw sizing.
- Intuitive Interface: 5.0-inch HD IPS touchscreen with user-friendly controls.
- Comprehensive Detection Modes: Full Wave, RF, Envelope, Positive Half Wave, Negative Half Wave.
- B-Scan Imaging: Up to 700 A-scan composites with φ2 mm resolution.
- Long Battery Life: 7.4 V 8000 mAh Li-ion battery providing up to 12 hours of operation.
- Fast Charging: Supports PD fast charging via standard Type-C.
- Rugged Design: Compact and durable housing for harsh environments.
Figure 2: Detailed view of the GUF750's touchscreen interface.
3. Specifications
Performance Parameters
| Parameter | Value |
|---|---|
| Bandwidth | 0.1 MHz – 20 MHz |
| Gain | 120 dB, steps of 0.1 dB, 0.6 dB, 1 dB, 2 dB, 6 dB |
| Filters | Broadband, 1M, 1.25M, 2.5M, 5M, 10M, 15M, 1M–5M |
| Sampling Rate | 100 MSPS (hardware), 400 MSPS (equivalent) |
| Resolution | 40 dB |
| Dynamic Range | 32 dB |
| Sensitivity Margin | 50 dB |
| Vertical Linearity | 1.8% |
| Horizontal Linearity | 0.5% |
Pulse Parameters
| Parameter | Value |
|---|---|
| Pulse Modes | Spike, Square, Bi-Square |
| Pulse Voltage | 25 V – 300 V, adjustable in 25 V steps |
| Pulse Width | 0 ns – 500 ns, continuously adjustable, 5 ns steps |
| Pulser Damping | Adjustable (Strong: 100 Ω / Weak: 1000 Ω) |
| PRF | Auto (200 Hz – 1 kHz) or Manual (0 – 10 kHz) |
Detection & Measurement
| Parameter | Value |
|---|---|
| Detection Modes | Full Wave, Positive Half Wave, Negative Half Wave, RF, Envelope |
| Detection Range | 10 m (longitudinal wave in carbon steel), step size 100 mm, 10 mm, 0.1 mm |
| Gate Modes | Independent Gate A, Gate B |
| Gate Alarms | Gate A/B alarms, Loss-of-Echo / Arrival-of-Echo |
| Measurement Modes | Peak, Leading Edge, J-Leading Edge |
| Quantitative Modes | DAC curve, AVG (DGS) curve |
| Flaw Detection Standards | AWS D1.1/D1.5, NB/T 47013, GB/T 29712, GB/T 11345 |
Probes & Channels; Imaging & Data
| Parameter | Value |
|---|---|
| Probe Channels | 200 groups, supporting create, preview, delete, rename, overwrite, restore |
| B-Scan Imaging | Up to 700 A-scan composites, max resolution φ2 mm |
| Data Storage | 8 GB SD card |
| Save Options | Single frame, multi-frame recording (≤500 frames), screen capture, B-scan capture |
Display & Interfaces; Power & Battery
| Parameter | Value |
|---|---|
| Display | 5.0" HD 800×480 IPS LCD |
| Probe Interface | Dual LEMO-00 C5 |
| Output Interfaces | Type-C1, Mini USB |
| Battery | 7.4 V 8000 mAh Li-ion, up to 12 hours operation |
| Charger | PD fast charging, standard Type-C (100–240 V, 50–60 Hz) |
Figure 3: GUF750 accessories including charger, probe, and cables.
4. Setup
4.1 Unpacking and Inspection
Carefully unpack the GOYOJO GUF750 and all accessories. Verify that all components listed in the packing list are present and undamaged. The standard package includes the GUF750 main unit, a probe, connecting cables, a charger, and a carrying case.
Figure 4: GUF750 and accessories in carrying case.
4.2 Charging the Device
- Connect the provided Type-C charger to the Type-C1 port on the GUF750.
- Plug the charger into a standard power outlet (100–240 V, 50–60 Hz).
- The device supports PD fast charging. Allow sufficient time for a full charge before initial use. The battery indicator on the screen will show charging status.
4.3 Connecting the Probe
- Identify the appropriate ultrasonic probe for your testing application.
- Connect the probe cable to one of the dual LEMO-00 C5 probe interfaces on the GUF750. Ensure a secure connection.
- If using a protective casing, ensure it is properly fitted around the device.
Figure 5: GUF750 with protective casing.
5. Operating Instructions
5.1 Powering On/Off
- To power on, press and hold the power button until the screen illuminates.
- To power off, press and hold the power button until the shutdown prompt appears, then confirm.
5.2 Basic Navigation and Controls
The GUF750 features a 5.0-inch HD IPS touchscreen for primary interaction, supplemented by physical buttons for quick access to common functions.
Figure 6: Front view of the GUF750 with screen and control buttons.
- Touchscreen: Tap, swipe, and pinch to navigate menus, adjust parameters, and zoom waveforms.
- Rotary Knob: Used for fine-tuning parameters and menu selection.
- Function Buttons: Dedicated buttons for common operations like gain adjustment (+/-), auto gain, waveform freeze, and gate controls.
5.3 Selecting Detection Modes
Navigate to the 'Detection Modes' menu on the touchscreen to select from:
- Full Wave
- Positive Half Wave
- Negative Half Wave
- RF (Radio Frequency)
- Envelope
5.4 Adjusting Pulse Parameters
Access the 'Pulse Parameters' menu to configure:
- Pulse Modes: Spike, Square, Bi-Square.
- Pulse Voltage: Adjust from 25 V to 300 V in 25 V steps.
- Pulse Width: Continuously adjustable from 0 ns to 500 ns in 5 ns steps.
- Pulser Damping: Select between Strong (100 Ω) and Weak (1000 Ω).
- PRF (Pulse Repetition Frequency): Set to Auto (200 Hz – 1 kHz) or Manual (0 – 10 kHz).
5.5 Using Gates and Alarms
The device supports independent Gate A and Gate B. Configure gate settings and alarms:
- Gate Alarms: Set for Loss-of-Echo or Arrival-of-Echo conditions.
- Gate Position and Width: Adjust using the touchscreen or rotary knob to define the inspection area.
5.6 Data Storage and Management
The GUF750 comes with an 8 GB SD card for data storage.
- Save Options: Single frame, multi-frame recording (up to 500 frames), screen capture, B-scan capture.
- Probe Channels: Store up to 200 probe configurations, allowing for creation, preview, deletion, renaming, overwriting, and restoring.
- Data Transfer: Use the Mini USB or Type-C1 interface to connect to a computer for data transfer.
6. Maintenance
6.1 Cleaning
- Regularly clean the device's screen and casing with a soft, dry cloth.
- For stubborn dirt, use a slightly damp cloth with mild soap, then wipe dry immediately.
- Do not use abrasive cleaners or solvents, as they may damage the screen or casing.
- Ensure probe interfaces are clean and free of debris.
6.2 Storage
- When not in use, store the GUF750 in its protective carrying case in a cool, dry place.
- Avoid exposing the device to extreme temperatures, high humidity, or direct sunlight for prolonged periods.
- Ensure the battery is partially charged (around 50%) before long-term storage to prolong its lifespan.
6.3 Battery Care
- Charge the battery regularly, even if the device is not in frequent use.
- Avoid completely draining the battery before recharging.
- Use only the provided or approved charger to prevent damage.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on. | Low or depleted battery. | Connect the device to the charger and allow it to charge for at least 30 minutes before attempting to power on again. |
| No waveform displayed. | Probe not connected properly; incorrect probe settings; couplant not applied. | Ensure the probe is securely connected. Check probe parameters in settings. Apply ultrasonic couplant to the test surface. |
| Inaccurate readings. | Improper calibration; incorrect material settings; surface condition. | Perform a calibration using a known standard. Verify material velocity settings. Ensure the test surface is clean and smooth. |
| Touchscreen unresponsive. | Software glitch; extreme temperature exposure. | Restart the device. If the issue persists, ensure the device is within its operating temperature range. |
| Data transfer issues. | Incorrect cable; driver issues on PC; full SD card. | Use the correct USB cable. Ensure necessary drivers are installed on your computer. Check SD card storage and clear unnecessary files. |
8. User Tips
- Calibration is Key: Always perform a proper calibration before starting any critical inspection to ensure accurate results. Use appropriate calibration blocks for the material and probe type.
- Couplant Application: Ensure a consistent and sufficient layer of ultrasonic couplant is applied between the probe and the test surface to facilitate sound transmission.
- Environmental Considerations: While rugged, avoid prolonged exposure to extreme dust, moisture, or temperature fluctuations to maintain device longevity and performance.
- Regular Software Updates: Check the manufacturer's website periodically for any available firmware updates to ensure optimal performance and access to new features.
Figure 7: GUF750 with wedge probe and calibration block.
9. Warranty and Support
9.1 Warranty Information
The GOYOJO GUF750 Ultrasonic Flaw Detector typically comes with a 1-year warranty from the date of purchase. This warranty covers manufacturing defects and malfunctions under normal use. Please refer to your purchase documentation for specific terms and conditions, as warranty policies may vary by region or retailer.
9.2 Technical Support
For technical assistance, troubleshooting beyond this manual, or warranty claims, please contact your authorized GOYOJO dealer or the manufacturer's customer support. Have your product model (GUF750) and serial number ready when contacting support.
