Non destructive testing technology is adopted for defects of mechanical parts

Date：2021-09-07 14:39:22Views：962

Modern industrial production is inseparable from the use of various machinery. With the acceleration of the pace of industrial production, the loss of various parts in mechanical equipment is increasing. Once there is a defect, it will cause hidden dangers to mechanical equipment and may also pose a threat to the life safety of producers. Therefore, the defect detection of mechanical parts is very important. Mechanical equipment parts are indispensable basic conditions for modern industry. There is a growing demand for mechanical equipment parts in all walks of life. The quality of mechanical parts directly affects the service life of mechanical equipment. Once the mechanical parts are defective, it will lead to the potential failure of the equipment, and even endanger the life safety of the mechanical equipment operators. Therefore, on the premise of not damaging or affecting the service performance of the tested object, it is necessary to detect whether the parts have defects or non-uniformity, give the information such as the size, position, performance and quantity of defects, and then judge the technical condition of the tested object.

The defects of mechanical parts are mainly surface defects and internal defects. Surface defects can usually be observed directly on the part surface with the naked eye or with ordinary testing equipment. However, the internal defects of parts are often difficult to find through the naked eye and external testing equipment. The common causes of internal defects are produced during forging or casting of parts, with pores, looseness, cracks, etc. Large volume and large axial extension.

For the detection of internal defects, the traditional method is destructive detection, that is, cut the parts and soak them in acid in order to see the internal defects. Using traditional destructive testing is not only time-consuming and laborious, but also the same defects will have different judgment levels due to different detection levels of testers. At the same time, once the sampled parts are found to be free of defects, it will also cause certain losses to the manufacturer. Therefore, the nondestructive testing method will be used to detect the defects of mechanical parts.

X-ray nondestructive testing equipment is mainly used for nondestructive testing of mechanical parts

The X-ray generator of flaw detector is mainly composed of X-ray tube and high-voltage power supply. The X-ray tube consists of a cathode and an anode installed in a vacuum glass shell. The cathode is a tungsten lamp installed in a focusing cup. When the lamp is energized and heated, the electrons evaporate, and the focusing cup focuses these electrons into a beam and shoots directly at the target embedded in the copper anode. High voltage is applied between the two poles of the X-ray tube to accelerate the electrons to a high speed before shooting at the target. The target is generally made of refractory metals with high atomic number such as tungsten, platinum, gold and tantalum. High speed electrons bombard the target to produce X-rays. When the X-ray tube works, the target will generate a lot of heat, and appropriate measures must be taken to export the heat.

The X-ray generator is a combined structure, and the X-ray tube, high-voltage transformer (including X-ray tube filament winding) and insulating gas (SF6) are encapsulated in a barrel aluminum shell. The X-ray generator is equipped with fan and radiator for cooling. The insulating gas (SF6) used has good dielectric properties for high voltage. The X-ray generator mainly includes X-ray tube, high voltage transformer, barometer, connecting cable socket and alarm lamp socket.

Previously, the term nondestructive testing was first called flaw detection or nondestructive testing, and different methods were also called flaw detection, such as radiographic flaw detection, ultrasonic flaw detection, magnetic particle flaw detection, penetrant flaw detection, etc. This title or writing is widely spread and has been used. So far, its utilization rate is no less than that of nondestructive testing.