I. Working Principle

Helium leak detection equipment leverages the unique properties of helium gas for inspection. Helium boasts a low density, small molecules, easy diffusion, and stable chemical properties, making it an ideal gas for leak detection. When helium is injected into or around the workpiece under test, if there is a leak, helium will quickly escape from the leakage point and enter the surrounding air or vacuum environment. At this point, by detecting the helium concentration in the environment with a helium mass spectrometer leak detector, it is possible to determine whether the workpiece has a leak, and if so, automatically assess the severity of the leak.

II. Operation Steps

Taking the vacuum chamber helium leak detection system as an example, its operation steps include the following aspects:

1. Workpiece Scanning

Use a dedicated barcode scanner to accurately scan the barcode or QR code on the workpiece.

Upon successful scanning, the computer interface will immediately display the scanned barcode data, ensuring accuracy and traceability of information.

2. Installing the Workpiece and Initiating Detection

Place the workpiece into the dedicated fixture inside the test chamber, ensuring its stability without shaking.

Close the vacuum chamber and initiate the preset detection cycle program to ensure the detection process follows the established sequence.

3. Chamber Detection

Perform vacuum evacuation on the vacuum chamber to detect the presence of major leaks.

If no major leaks are detected, proceed to the next step; otherwise, the system will automatically issue an alarm and terminate the detection.

4. Workpiece Evacuation

Evacuate the workpiece until it reaches the preset vacuum level.

This step aims to remove air and other impurities from the workpiece, preparing it for subsequent detection.

5. Detecting Major Leaks in the Workpiece

Inject helium into the workpiece interior and continuously observe changes in sensor readings.

If the drop in sensor readings does not exceed the preset limit, it indicates no major leaks in the workpiece, and detection can continue; otherwise, the system will issue an alarm and end the detection.

6. Vacuum Chamber Background Signal Suppression

During detection, to ensure accuracy, it is necessary to detect the background signal within the vacuum chamber.

If the background signal is too high, the system will perform suppression to eliminate its impact on detection results.

7. Filling the Workpiece with Helium and Detecting Micro-Leaks

Fill the workpiece interior with helium to the preset pressure level to detect micro-leaks.

Use a helium mass spectrometer leak detector to detect helium signals within the workpiece.

If the helium signal detected by the leak detector exceeds the preset limit, it indicates the presence of micro-leaks, and the micro-leak indicator light will illuminate; otherwise, the qualified indicator light will illuminate, and the system will automatically mark the workpiece.

8. Recycling Helium and Conclusion

After detection, recycle the helium within the vacuum chamber to ensure efficient resource utilization.

Once recycling is complete, evacuate the air within the vacuum chamber to the preset vacuum level.

Open the vacuum chamber and carefully unload the workpiece, marking the end of the entire workpiece detection process.

III. Equipment Composition

Helium leak detection equipment typically consists of the following components:

1.Vacuum System: Used to evacuate air from the vacuum chamber, creating a vacuum environment.

2.Gas Filling System: Used to inject helium into the workpiece.

3.Leak Detection Instrument: Such as a helium mass spectrometer leak detector, used to detect helium concentration in the environment.

4.Control System: Used to control the entire detection process, including setting and adjusting parameters like vacuum level, gas filling volume, and detection time.

5.Display and Recording Module: Used to display detection results and record detection data.

IV. Precautions

When using helium leak detection equipment, it is necessary to strictly follow operating procedures to avoid safety issues or detection errors caused by improper operation.

Helium is a rare gas with a relatively high price, so attention should be paid to conservation and recycling during use. Our company's helium leak detection system is equipped with a helium recovery and purification unit, enabling the recycling of helium.