ISO 17405:2014 pdf free

ISO 17405:2014 pdf free.Non-destructive testing一Ultrasonic testing一Technique of testing claddings produced by welding, rolling and explosion
A depth zone providing optimum sensitivity is defined (see Annex A) by the size of the transducer used in the probes. The position of this zone should be selected according to the expected position of the discontinuities.
A depth zone providing optimum sensitivity is defined (see Annex A) by the size of the transducers used in the probes and their roof angle. The position of this zone should be selected according to the expected position of the discontinuities.
The beam angle should be between 65° and 80°. The skewing angle, and the shape and size of the transducers, shall be selected so that the depth range for optimum sensitivity (see Annex A) covers the expected position of the discontinuities.
Range setting of the ultrasonic instrument for accurate localization of discontinuities when using dual-element probes can be carried out using reference blocks (see Reference [2]) as shown in Figure 1 or Figure 2 for example, made of materials that are similar to the test object, or it can be carried out on the test object itself.
In the case of a dual-element straight-beam probe, the probe can, for example, be placed on the various steps of a stepped wedge calibration block. The front edge of the associated echo shall be set on the appropriate marks on the screen by adjusting the zero shift and the sweep (velocity). When dual-element angle-beam probes are used on a reference block as shown in Figure 2, for example, the shortened projected distances (distance between the front edge of the probe and the projection of the reflection point on the test surface) shall be lined up with the appropriate marks on the screen. In this manner,it is possible to read the position of a reflection point directly on the screen, i.e. for the setting with shortened projected distances as well as with depth positions.
NOTE 1 It is recommended to mark the range of any discontinuities to be detected on the screen according to their depth position (normally corresponding to the thickness of the cladding).
When straight beam probes are used, the range of the ultrasonic instrument can be calibrated using multiple echo series from a plane-parallel steel plate of known thickness and sound velocity (e.g. calibration block No. 1 according to ISO 2400).
NOTE 2 Since when dual-element angle-beam probes are used for longitudinal waves, transverse waves are also generated, care has to be taken to ensure that no erroneous indications of transverse waves are used during the setting procedure. In any case, these indications have a considerable larger time- of-flight than those of longitudinal waves.ISO 17405 pdf download.