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What are the implementation standards for ultrasonic testing of stainless steel plates? What are they respectively?
1 Topic Content and Scope of Application This standard specifies the ultrasonic inspection methods, comparative test blocks, inspection instruments and equipment, inspection conditions and procedures, defect testing and evaluation, quality grading of steel plates, inspection reports, etc. for special purposes such as boilers, pressure vessels, bridges, and buildings. This standard is applicable to ultrasonic inspection of steel plates (excluding austenitic stainless steel plates) with a thickness of 6-200mm for special purposes such as boilers and pressure vessels, bridges, and buildings. 2. Reference standard ZBY 230 A type pulse reflection ultrasonic flaw detector General technical conditions GB 8651 Metal sheet ultrasonic flaw detection method 3. General provisions 3.1 Personnel engaged in steel plate ultrasonic inspection must undergo training and obtain ultrasonic inspection personnel qualification certificates issued by various national departments. The issuer of the report must hold a Level II or above ultrasonic inspection qualification certificate. 3.2 Inspection methods can include manual contact method, liquid immersion method (including local liquid immersion method and automatic inspection method using piezoelectric or electromagnetic ultrasonic probes). The ultrasonic wave modes used in 3.3 can be longitudinal waves, transverse waves, and plate waves. 3.4 When using the first two methods described in 3.2, direct beam probe inspection is the main method, followed by oblique probe inspection, and coupling agents such as water and oil can be used. 4 Comparative test blocks 4.1 The materials of the comparative test blocks and test plates should be the same or similar to the acoustic performance of the tested steel plate. And ensure that there are no defects with a flat bottom hole equivalent to or greater than ф 2mm inside. When using a twin crystal straight probe to inspect steel plates with a thickness not exceeding 20mm, the sensitivity test block used is shown in Figure 1, and the performance of the twin crystal straight probe should meet the requirements of Appendix A. When using a single straight probe to inspect steel plates, the sensitivity should comply with the provisions of Figure 2 and Table 1. Figure 1 Test block for double crystal probe inspection with plate thickness ≤ 20mm Figure 2 Comparison test block for single straight probe inspection Note: The variation of verticality a with the thickness of the test block is shown in Table 2. Table 1mm test block number: The interval between the thickness inspection surface of the inspected steel plate and the flat bottom hole, S, and the thickness of the test block T 1 ≥13~20 7≥15 2 ＞20~40 15≥20 3 ＞40~60 30≥40 4 ＞60~100 50≥65 5 ＞100~160 90≥110 6 ＞160~200 140≥170 Table 2 Test block thickness ≥ 13-20>20-40>40-60>60-100>100-160>160-200a 0.10 0.15 0.20 0.25 0.30 4.0 4.4 When using piezoelectric or electromagnetic acoustic probes for automatic ultrasonic inspection, the test block should be cut from the finished plate, its long side should be parallel to the rolling direction, the end face should be straight, and the thickness tolerance should be less than 2% of the plate thickness. The location of artificial defects is shown in Figure 3. According to the actual situation of the automatic inspection