Valve Leakage and Hydraulic System Leakage Detection Methods

Overview of Valve detectors

Valve detectors are used to accurately detect internal blockages or leaks in valves and hydraulic systems during online operation. Using an ultrasonic valve detector to check for hydraulic circuit faults can quickly and easily identify internal leaks. The ultrasonic valve detector collects sample readings along the circuit in contact mode. Inspectors can clearly define the direction of flow, and more importantly, the source of the fault, even in high-noise areas. The internal leakage that passes through the seal on the hydraulic plunger generates small bubbles in the oil, and as they reach the non-pressure side from the pressure side, they sequentially “burst”. These small explosions generate ultrasonic energy, which is easily detected by ultrasonic valve detectors, and interference from ultrasonic waves is eliminated by adjusting the frequency of the detector.

Typical applications of valve detectors:

Typical application examples – “Valve leakage and hydraulic system leakage detection methods”

1. Place the instrument against the upstream pipeline of the valve to measure the system’s environmental ultrasound value.

2. Use the up and down arrow buttons on the ultrasonic detector host to adjust the sensitivity of the instrument, ensuring that the arrow pointer on the LCD screen is hidden to measure the system background signal while paying attention to the dB reading on the display screen.

3. Attach the instrument to the downstream pipeline of the valve and listen for the leakage signal. If the dB reading on the display screen is less than or equal to the reading at point A, it indicates that the valve is not leaking; If the dB reading at point B increases relative to point A, it indicates that the valve is leaking.

4. Finally, place the detector against a downstream pipeline below point B to confirm the leakage point. If the valve leaks, the dB reading at point C in the diagram should be less than the reading at point B; If the dB reading at point C is greater than the reading at point B, the leakage location should be somewhere downstream of the pipeline.

5. If the valve is in the closed state, almost no sound can be heard. If the valve is in the open state, continuous or intermittent sounds can be heard
Flowing sound, which is the sound produced when the medium flows through the valve body.

6. Water treatment plants can refer to the digital readings of ultrasonic detectors for valve calibration and setting work after maintenance. Water treatment equipment The reading of the backup gate valve is generally less than 5dB μ V.