Non-destructive testing refers to the inspection and testing of the structure, properties, condition and defects of the interior and surface of wood without damaging or affecting the performance of the wood. the object tested or the internal organization of the object tested. . method. Wood inspection is generally divided into macroscopic inspection and microscopic inspection. Microscopic inspection typically takes a small sample of wood and uses instruments or chemical reagents to study the microscopic structure to determine the type of wood or material properties. Macroscopic inspection mainly detects internal defects, physical properties, structural strength, etc.
Research on non-destructive testing of artificial panels mainly focuses on internal defect detection, surface defect detection, density detection, moisture content detectionsaid, etc. Among them, the methods used for non-destructive testing of internal defects are mainly the X-ray method and the ultrasonic method. Mature detection technologies and devices have been formed and have been well applied in actual production.
Non-destructive testing can be divided into six categories and about 70 types, but the most common in practical applications are: visual inspection (VT), radiography ( RT), ultrasound testing. (UT), magnetic particle inspection (MT), penetrant inspection (PT), eddy current (ECT), acoustic emission (AE), time-of-flight ultrasonic diffraction (TOFD). Toft detection is ultrasonic transit time diffraction (TOFD).
In addition to the eight types mentioned above, there are three unconventional detection methods worth noting: leak testing (LT); the guided wave (PA) test;
Detailed information
Characteristics of non-destructive testing:
1. Non-destructive
In. get testing At the same time, no parts are lost unless defective products are rejected. Therefore, the scope of the inspection is not limited by the number of parts. A sampling inspection may be carried out and a general inspection may be used if necessary. Therefore, it is more flexible (general inspection and random inspection can be carried out) and more reliable.
2. Mutual tolerance
Different inspection methods can be used for the same part at the same time or sequentially and the same inspection can be carried out repeatedly; It is also an advantage to be non-destructive.
3. Dynamicity
Non-destructive testing methods can inspect parts in use and timely examine the cumulative impact of the product's operating period.Thus, the structure failure mechanism can be identified.
4. Rigor
First of all, non-destructive testing requires special instruments and equipment; they also require specially trained inspection personnel to operate in accordance with strict procedures and standards.
5. Divergence of test results
Different testers may have different test results for the same specimen. Especially during ultrasonic inspection, the same inspection item must be completed by two inspectors. A “consultation” is required.
In summary, the characteristics of non-destructive testing are: non-destructive, mutual tolerance, dynamics, rigor and test results. Consistency of results, etc.
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