The whole process of production of products of Shinda company adopts 100% online testing to ensure 100% qualified rate of products delivered.Online testing includes ultrasonic nondestructive testing, eddy current nondestructive testing and on-line caliper.Online testing includes ultrasonic nondestructive testing, eddy current nondestructive testing and on-line caliper.The ultrasonic wave generated by the sound source propagates in the specimen and interacts with the tested material and its defects, so that its propagation direction or characteristics are changed, change after ultrasonic be received through testing equipment, and can carries on the processing and analysis, and it can also be processed and analyzed to evaluate the specimen itself and its internal defects and defects characteristics according to the received ultrasonic features.Ultrasonic inspection of our company adopts the method of probe rotation and straight ahead of steel tubing.Rotating ultrasonic testing equipment carries out bidirectional detection to the longitudinal of the steel pipe and bidirectional detection to the circumferential (horizontal) of the steel pipe. There are 2 groups of longitudinal probes in the circumferential direction, each group contains 2 probes, a total of 4 probes (bidirectional detection),and 2 groups of circumferential distribution in transverse probe group, each group contains 2 probes, a total of 4 probes (bidirectional detection).The system is equipped with 8 channels, 4 channels vertically and 4 channels horizontally.Full-wall thickness longitudinal and transverse defects of steel tube are detected. In the process of automatic detection, the blind area of the end is small and 100% cross-sectional scanning. When the system detects a defect, the system will automatically generate audible and visual alarm.。Eddy current detection means that the conductor is close to the coil with alternating current, and the alternating magnetic field is established by the coil.The alternating magnetic field passes through the conductor and is induced by electromagnetism, creating an eddy current in the conductor.The eddy current in the conductor produces its own magnetic field, and the effect of the eddy current field also changes the voltage and impedance of the coil caused by the original magnetic field.Therefore, the intensity and distribution of eddy current will be affected when defects or measured metal materials change on or near the conductor surface. The change of eddy current also causes the change of voltage and impedance of detection coil.On the basis of this change, we can indirectly know the existence of defects in conductors and the properties of metal materials are quite different.Of various defects in metal materials,  most of which are surface defects,the eddy current method can be used for testing, can quickly nimbly out on the surface of the metal material cracks, porosity, slag inclusion, peeling, pits, transverse crack, such as scars, for the detection of metal tube, there is no contact or coupling medium, so the detection speed is high, especially suitable for online general inspection. On-line caliper measure product size in real time,and it will alarm when it exceeds the standard specification.The double test of ultrasonic nondestructive testing and eddy current nondestructive testing can ensure product quality 100%.