Ultrasonic thickness gauges are widely used in fields such as petroleum, chemical, metallurgical, shipbuilding, aviation, and aerospace. They can measure the thickness of various plates, pipes, pressure vessels, and processed parts, and monitor the degree of thinning after corrosion during use.
The ultrasonic probe emits pulses to the surface of the object being measured, and the pulses are reflected back to the probe when they reach the material interface. By accurately measuring the time of ultrasonic propagation in the material and combining it with the known material sound velocity, the thickness of the measured material can be determined, which is mainly composed of two parts: the host and the probe. The host circuit includes three parts: the transmission circuit, the reception circuit, and the counting display circuit. The transmission circuit generates high-voltage shock waves to excite the probe to generate ultrasonic transmission pulse waves, and the reception circuit receives reflected waves. After counting and processing by the microcontroller, the thickness value is displayed on the LCD screen.
measurement method
General measurement: Use a probe to measure the thickness twice at a certain point. The dividing surfaces of the probe should be 90 ° to each other during the two measurements, and the smaller value should be taken as the thickness value of the measured workpiece; When the measurement value is unstable, take multiple measurements within a circle with a diameter of approximately 30mm centered on a measuring point, and take the smaller value of * as the thickness value of the measured workpiece.
Accurate measurement method: Increase the number of measurements around the specified measurement points, and represent thickness changes with equal thickness lines.
Continuous measurement method: Use a single point measurement method to measure continuously along a specified route, with an interval of no more than 5mm.
Grid measurement method: Draw a grid in a designated area, measure the thickness at each point, and record it. It is commonly used for monitoring corrosion of high-pressure equipment and stainless steel lining.
Operation steps:
Calibration: Use standard test blocks (such as steel blocks) to calibrate the instrument's sound velocity.
Surface treatment: Clean the measuring surface, remove dirt, floating rust, or loose coatings.
Couplant application: apply a proper amount of coupling agent (such as glycerin, water-based gel) on the surface of the probe and the material to remove air.
Measurement: Press the probe vertically onto the surface of the material and read the thickness value.