ISO 5948 pdf download – ISO 5948 pdf Railway rolling stock material-Ultrasonic acceptance testing

ISO 5948 pdf download – ISO 5948 pdf Railway rolling stock material-Ultrasonic acceptance testing.
6 Surface condition of the products
6.1 Unless otherwise agreed, independent of the surface condition in which the product is to be debvered, ultrasonic testing may be carried out erther in the unmach.ned or machined condition, provided that the requirements of 6.2 to 6.4 are observed.
6.2 The surface condition of both the testing and reflecting surfaces of the products shall be such that there is no interference with the test.
6.3 When ultrasonic acceptance tests are carried
Out On products in the unmechined condiflon. any
scale shall tightly adhere to the rnetalbc surface and
shall be sufficiently smooth to meet the conditions of
6.2.
6.4 When product to be ultrasonically tested ere machined before testing, the operation shall ensue thet a surface finish suitable for ultrasonic testing is achieved.
7 Equlpm.nt characteristics
1.1 Typ. of equipment
A suitable ultrasonic pulse echo instrument with a gain control calibrated in decibels shell be used.
7.2 Probes
Unless otherwise agreed, the requirements in
table 1, columns 7 and 8, shall apply.
7.3 Other facilities
Adequate facilities shall be available, to ensure that prodi.ict$ not complying w1h the requirements are identified accordingly.
8 Couplants
8.1 In order to ensure that adequate transmes.on of ultrasonic energy is obtained between the probe and the material, a suitable coibnt shall be applied between the probe and the product. This can also be achieved by the mmerion of the component and the probe in the couplant.
8.2 The same coupLant shall be used ton the calibrateon of the ultrasonic pulse echo instrument and for carrying out the tests.
9 Setting of the sensitivity of the instrument
9.1 General
The setting of the sensitivity of the instrument shaft be carried out under the same conditions (see 7.2 and clause 8) as the tests themselves.
In the case of discontinuity-detection tests, in each case the sensitivity shall be set so that, within the area to be scanned outside the “dead zone” (see note 2 to table 1), a reference reflector with a diameter specified as acceptance standard in clause 12 can. irrespective of its distance from the surface to be scanned, be detected positively.
NOTF 3 Calibration blocks applid for estabiis)ün the DGS diagrams or for setting the sensitivity according to
9.2, 9.3 or 94 shall have an acoustic attenuation similar to that of the wheels or tyres to be tested.
9.2 Sensitivity setting for wheels or tyres
9.2.1 For wheels or tyres to be tested with the beam in an axial or radial direction and to be evaluated by the distance-gain-size (DGS) method, the sensitivity is set with the help of the DGS diagram and the backwall echo occurring when axially testing the tyre or the wheel rim.
9.2.2 For wheels and tyres to be evaluated by the comparison method, the sensitivity shall be set:
a) when being tested with the beam in an axial direction, with the help of a calibration block of the type shown in figure 1 and an internal reference standard of the type shown in figure 2 (sets note 4) (both may be combined in the same block); or
b) when being tested with the beam in a radial direction, with the help of a calibration block of the type shown in figure 3.
NOTE 4 In this International Stdard, interns reference standard” means a calibration block with a bore on the backwall with the position, form, depth and diameter indicated in figure 2.
9.3 Sensitivity setting for axles
9.3.1 For axles to be tested with the beam in a radial direction and to be evaluated by the DGS method, the sensitivity is sot with the help of the DOS diagram and the occurring backwall echo.