AS ISO 17643 pdf download

AS ISO 17643 pdf download.Non-destructive testing of welds — Eddy current testing of welds by complex- plane analysis
1  Scope
This International Standard defines eddy current testing techniques for detection of surface breaking and near surface planar discontinuities, mainly in ferritic materials (weld material, heat-affected zones, base material). Eddy current testing can also be specified for use with non-ferritic materials, for example in an application standard. The techniques can be applied to coated and uncoated objects during fabrication and in service, both onshore and offshore. Eddy current testing can be carried out on all accessible surfaces and on welds of almost any configuration. Unless otherwise specified at specific items in this International Standard, the general principles of ISO 15549 apply. NOTE  Eddy current testing is usually performed in the as-welded condition. However, the accuracy of the results can be affected by very rough surface finishes.
3  Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12718 apply.
4  Personnel qualification
Non-destructive testing shall be performed by qualified and capable personnel. It is recommended that personnel are qualified in accordance with ISO 9712 or an equivalent standard at an appropriate level in the relevant industry sector.
6  General applications
6.1  Essential variables Prior to eddy current testing, the following essential items shall be specified in accordance with ISO 15549: — certification of testing personnel; — testing plan; — testing equipment; — calibration of the equipment; — calibration blocks; — acceptance criteria; — recording of indications; — reporting format; — actions necessary for non-acceptable indications. 6.2  Additional information Prior to eddy current testing, the following information should be specified. Further information may be necessary for determination of the nature of the discontinuities and the composition or grade of the base material: — type of filler metal; — location and extent of welds to be tested; — weld surface geometry; — surface conditions; — coating type and thickness. 6.3  Surface conditions Eddy current testing can be used to detect surface cracks through non-metallic coatings up to a thickness of 2 mm. For coating thicknesses greater than 2 mm, the sensitivity of the test method shall be demonstrated in advance before eddy current testing is used. NOTE 1  Eddy current testing is dependent on close contact between the probe and the test surface. For effective eddy current testing of welds, it should be noted that local adverse weld form, excessive weld spatter, scale, rust and loose paint can influence sensitivity by separating the probe from the test object and by inducing noisy responses. NOTE 2  It should be noted that some types of conductive coating, such as thermally sprayed aluminium and lead, can seriously influence the results as they can deposit electrically conductive metallic material in cracks open to the surface. Cracks covered with such a metallic deposit are not always indicated by this method.6.4  Equipment 6.4.1  Instrumentation (excluding probe) 6.4.1.1  General The instrument used for eddy current testing in accordance with this International Standard shall be capable of analysis and display in the complex plane. The amplitude and phase of eddy current signals shall be measurable. 6.4.1.2  Frequency The eddy current instrumentation shall be able to operate at a selected frequency within the range 1 kHz to 1 MHz. 6.4.1.3  Signal display The display shall include the facility to freeze eddy current signals on screen until reset by the operator. The trace shall be clearly visible under all lighting conditions expected during testing. 6.4.1.4  Phase control The phase control shall be able to give complete rotation of displayed signals (360 °) in steps of no more than 10 ° each. 6.4.2  Surface probes 6.4.2.1  Probes for measuring coating thickness and material evaluation relative to calibration block The probe shall operate in the absolute mode at a selected frequency in the range from 1 kHz to 1 MHz. All the probes shall be clearly marked with their operating frequency range.