A three-dimensional nondestructive testing method for internal defects of large high-temperature blades

Abstract

A three-dimensional non-destructive testing method for internal defects of large high-temperature blades. Firstly, digital ray equipment is used to detect internal flaws on the front of gas turbine blades to obtain two-dimensional grayscale images, and the two-dimensional size and position of defects are obtained by processing the two-dimensional grayscale images, and then Carry out three-dimensional positioning of the internal defects of the blade, use the method of water immersion ultrasonic to locate the depth of the defect, judge the existence of the defect by the appearance of the defect echo signal; determine the distance between the defect and the detection surface by the position of the echo signal, and realize the defect positioning , the present invention combines the respective advantages of digital ray equipment and water immersion ultrasonic equipment to realize three-dimensional non-destructive testing of internal defects, and makes up for the shortcomings of traditional radiographic film photography that cannot detect three-dimensional information and industrial CT is expensive.

Description

technical field [0001] The invention belongs to the technical field of gas turbine non-destructive testing, in particular to a three-dimensional non-destructive testing method for internal defects of large high-temperature blades. Background technique [0002] The traditional large-scale high-temperature blades of gas turbines are detected by radiography, which has the advantages of intuition and reliability, and plays an important role in quality control in industrial production. However, this method can only display the two-dimensional information of the defect, and cannot provide the three-dimensional position and volume information of the defect. It can only be estimated by professional and technical personnel based on experience. There are complex detection processes, heavy workload, slow speed, and operating costs. High and susceptible to human subjectivity and other deficiencies. The non-destructive testing methods applied to internal defects of parts mainly include ...

AI Technical Summary

Problems solved by technology

However, low-power CT rays cannot penetrate nickel-based superalloy blades, so they cannot be measured; although high-power CT rays can penetrate, the price is very expensive. A high-power industrial CT equipment costs tens of millions. too expensive for business

Since the high-temperature blades of the gas turbine turbine are made of nickel-based superalloy, the attenuation rate of the radiation is very high, and the thickness that the radiation detection method can penetrate is very limited, and it is impossible to locate the defect in the depth direction; although the ultrasonic detection has a strong penetration ability, it cannot When the probe performs scanning detection, the plane of the probe needs to be parallel to the plane of the object to be measured. Therefore, it is difficult to select a suitable probe for scanning detection of objects with complex and irregular shapes such as high-temperature turbine blades.

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