1, ultrasonic testing

Ultrasonic testing is one of the non-destructive testing methods, non-destructive testing is not under the premise of damage to the workpiece macroscopical defects or measure the characteristics of various technical methods collectively. Dyed steel pipe conventional non-destructive testing methods are: Ultrasonic Testing (Radar); Radiographic Testing (abbreviated RT); Magnetic particle testing (abbreviated MT); Penetrant testing Penetrant Testing (abbreviated PT); Eddy Current testing (abbreviated ET);

2, ultrasonic flaw detector

The use of ultrasonic testing methods to detect the instrument called ultrasonic flaw detector. The principle is that when the ultrasonic wave propagates in the tested material, the acoustic characteristics of the material and the change of the internal structure have a certain influence on the propagation of the ultrasonic wave. Through the detection of the degree and condition of the ultrasonic wave, the technique of understanding the material performance and structure change Called ultrasonic testing. Ultrasonic testing methods are usually penetrating, pulse reflection, tandem and other ultrasonic testing is the use of ultrasound can penetrate the depth of metal materials, and from one section into another section, the reflection of the characteristics of the interface edge to check Part of the defect of the method, when the ultrasonic beam from the surface of the parts from the probe to the inside of the metal, encountered defects and parts of the bottom of the surface were reflected waves, the formation of pulse waveform on the screen, according to the pulse waveform to determine the defect location and size.

Pulse reflection type ultrasonic method compared with other non-destructive testing methods

The main advantages are:

① penetrating ability, detection depth of up to several meters;

② high sensitivity, can be found with about a few tenths of a diameter of the air gap reflectivity equivalent of the reflector;

③ in determining the internal reflector of the bit direction, size, shape and nature of the more accurate;

④ only from one side of the object to be tested;

⑤ can immediately provide defect test results;

⑥ safe operation, equipment, light.

The main drawbacks are:

① be operated by experienced people with caution;

② rough, irregular shape, small, thin or non-homogeneous material difficult to check.