1 Scope
This standard specifies the ultrasonic testing principle, ultrasonic testing methods, reference block, ultrasonic testing equipments, ultrasonic testing conditions, ultrasonic testing procedures, result evaluation and ultrasonic testing report for seamless steel tubes.
This standard is applicable to the ultrasonic testing for longitudinal and transverse defects of seamless steel tubes for various purposes. The testing methods stated in this standard are mainly applicable to test the defects that destroy the metal continuity of steel tubes, but can not effectively test laminar defects.
This standard is applicable to the inspection of tubes with an outside diameter greater than or equal to 6 mm, and with a wall thickness-outside diameter ratio less than or equal to 0.2. For tubes with a wall thickness-outside diameter ratio greater than 0.2, one of the methods specified in annex C shall be used by agreement between manufacturer and purchaser.
Electromagnetic ultrasonic testing may be carried out according to this standard.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this standard.For dated references, all subsequent modifications (excluding correction contents) or revisions are not applicable to this standard. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest editions of these documents are applicable.For undated references, the latest edition of the normative document referred to applies.
GB/T 9445 Non-destructive testing - Qualification and certification of personnel
YB/T 4082 Measurement method of comprehensive properties for automatic ultrasonic flaw detection system for steel tubes
JB/T 10061 Commonly used specification for A-mode ultrasonic flaw detector using pulse echo technique
3 Ultrasonic Testing Principle
Interconversion between electric energy and sound energy realized by ultrasonic probe and physical properties of ultrasonic traveling in an elastic medium are basis of steel tube ultrasonic testing principle. Ultrasonic beams emitted along a particular direction will generate wave reflection when encounter defects during travel in the tube, defect echo is picked up by ultrasonic probe, and then treated by defect detector to obtain defect echo signals and hereby give out quantitative defect indication.
4 Ultrasonic Testing Methods
