The AG-190 ultrasonic thickness gauge, as an intelligent measuring device, can measure the thickness and sound velocity of various materials based on the principle of ultrasonic measurement. It is widely used in industries such as petroleum, chemical, metallurgy, and shipbuilding, providing reliable support for equipment monitoring and part measurement. Its working principle revolves around the emission, propagation, reflection, and signal processing of ultrasonic waves, and the specific process is as follows:

Core workflow

（1）Ultrasonic emissionThe probe equipped with the instrument generates ultrasonic pulses during operation, which require the action of a coupling agent to smoothly penetrate the surface of the object being measured. The core function of a coupling agent is to eliminate air between the probe and the object being measured, ensuring that ultrasonic waves can be transmitted to the inside of the object being measured, and avoiding signal attenuation or distortion caused by air obstruction.

（2）Signal propagation and reflectionAfter the ultrasonic pulse enters the tested object, it will propagate along the interior of the material. When the pulse reaches the bottom surface of the measured object, a portion of the ultrasonic signal will be reflected by the bottom surface, forming an echo signal.

（3）Echo reception and time calculationAfter emitting the pulse, the probe will switch to the receiving state and capture the echo signal reflected back from the bottom surface of the measured object. The high-performance microprocessor inside the instrument calculates the round-trip time of ultrasonic waves from transmission to reception, which is a key parameter for calculating material thickness.

（4）Thickness calculation and displayBased on the basic principle of ultrasonic propagation and the sound velocity of materials, the instrument calculates the thickness of the measured object through a specific formula. The calculation formula is: H=(v × t)/2, where H is the measured thickness, v is the sound velocity of the material, and t is the propagation time of ultrasonic waves in the specimen for one round trip. After the calculation is completed, the thickness result will be displayed intuitively on the instrument screen, making it convenient for users to read.

Key auxiliary mechanisms

（1）Sound speed adaptation mechanismThe sound velocity of different materials varies. To ensure measurement accuracy, this instrument supports sound velocity adjustment within the range of 1000-9999 m/s. At the same time, if the material thickness is known, the measurement accuracy can be further optimized by reverse measuring the sound velocity to meet the measurement needs of various materials.

（2）Coupling status promptThe instrument has a coupling status prompt function. When the coupling effect between the probe and the measured object is poor, it will provide timely feedback to help the user adjust the operation, ensure stable propagation of ultrasonic waves, and avoid measurement errors caused by coupling problems.

（3）Calibration guarantee mechanismThe instrument has built-in probe zero calibration and two-point calibration functions, with standard calibration based on 4.0mm steel. Through calibration operations, possible system errors in the instrument itself and the probe can be corrected, providing a guarantee for long-term stable measurements.

The working principle of AG-190 ultrasonic thickness gauge is based on mature ultrasonic propagation characteristics, combined with high-performance hardware configuration and intelligent algorithms, to achieve thickness measurement of various ultrasonic conductive materials such as metals, plastics, ceramics, etc. Its compact and portable design and anti-interference ability enable it to adapt to complex industrial site environments, providing reliable measurement support for equipment maintenance and production processing in various industries.