1 Scope
This standard specifies the basic principle for the application of one-dimensional linear phased-array ultrasonic technology which adopts manual scanning or automatic (semi-automatic) scanning, the rules for selection of process parameters during testing, and the method to determine the location and dimension of flaws.
It is applicable to fine-grained steel welded joints with the thickness of 6mm to 200mm. For other fine-grained metal welded joints, this standard may be referenced after considering the change in sound velocity. For welded joints with thickness beyond the above range, this standard may be referenced after demonstrating that the instrument system has sufficient testing capability. For coarse-grained welded joints such as austenitic stainless steel, this standard may be referenced after considering the impact of signal-to-noise ratio and sound velocity anisotropy.
For other structural parts, rolled parts and forgings, this standard may be referenced after selecting the appropriate test block, calibration method and scanning method.
This standard may also be referenced after considering the changes in sound field characteristics and its impact on system calibration and testing when two-dimensional phased-array ultrasonic probe is used for testing.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 9445 Non-destructive testing- Qualification and certification of personnel
GB/T 12604.1 Non-destructive testing - Terminology - Terms used in ultrasonic testing
GB/T 23905 Non-destructive testing - Blocks for ultrasonic testing
JB/T 11731 Non-destructive testing - General specification for ultrasonic phased array probe
NB/T 47013.3 Nondestructive testing of pressure equipment - Part 3: Ultrasonic testing
3 Terms and definitions
For the purposes of this standard, the terms and definitions given in GB/T 9445 and GB/T 12604.1 as well as the following ones apply.
3.1
pitch
distance between the same sides or centers of two adjacent elements (as shown in Figure 1)
3.2
space between elements, gap between elements
gap between two adjacent elements (as shown in Figure 1)
3.3
active aperture
total length of element set activated at a time i.e.
Active aperture L=n×c-d
where,
L——the active aperture;
n——the number of active elements;
c——the pitch;
d——the gap between elements.
Foreword i
Introduction ii
1 Scope
2 Normative references
3 Terms and definitions
4 Testing technology level
5 Testing personnel
6 Testing equipment
7 Test blocks
8 Basic requirements
9 Testing preparation
10 Setting and calibration of testing system
11 Testing
12 Analysis and explanation of testing data
13 Testing report
Annex A (Normative) Element sensitivity difference and validity testing of phased-array probe
Annex B (Normative) Positioning accuracy testing of phased-array testing system
Annex C (Informative) Recommended scanning positions for other common forms of welded joints
