EN BS EN Licens k? DS-publikationen er p? DS-publikationstyper Dansk Standard udgiver forskellige publikationstyper.
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EN BS EN Licens k? DS-publikationen er p? DS-publikationstyper Dansk Standard udgiver forskellige publikationstyper. Typen p? Der kan v? Hvis der efter nr. DS-betegnelse angives p? Overensstemmelse med anden publikation: Overensstemmelse kan enten v? IDT: N? EQV: N? NEQ: N? MOD: N? Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member.
A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by July , and conflicting national standards shall be withdrawn at the latest by July This is one of three European Standards for ultrasonic examination.
Annex A is normative. Annexes B and C are informative. This European Standard applies to the ultrasonic examination of steel castings which have usually received a grain refining heat treatment and which have wall thicknesses up to and including mm.
For greater wall thicknesses, special agreements apply with respect to test procedure and recording levels. This European Standard does not apply to austenitic steels and joint welds. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision.
For undated references the latest edition of the publication referred to applies including amendments. EN , Non-destructive testing — Ultrasonic examination — Part 5: Characterization and sizing of discontinuities. EN , Non-destructive testing — Characterization and verification of ultrasonic examination equipment — Part 1: Instruments. EN , Non-destructive testing — Characterization and verification of ultrasonic examination equipment — Part 2: Probes.
EN , Non-destructive testing — Characterization and verification of ultrasonic examination equipment — Part 3: Combined equipment. EN , Welds in steel — Calibration block No. For wall thicknesses greater than mm, agreement shall be made between the parties concerned on the test procedure and also on the recording and acceptance levels.
The wall section shall be divided into zones as shown in Figure 1. These sections relate to the sizes of castings ready for assembly finish machined. These indications shall not exceed the limits given in Table 1. The area of indication with measurable length but with non-measurable dimension in through-wall direction shall be calculated according to the formula given in Figure 2.
The sizing of small planar discontinuities, as given in Figure 2, becomes more difficult with increasing beam-path length and sound-beam diameter. As a guide, these sizings are normally applied to a rim zone of 30 mm.
It makes the use of probes with focussed beams such as twin-crystal probes necessary. Indications with measurable dimensions are not permissible in severity level 1. The area of an indication with measurable length but non-measurable width shall be calculated in accordance with the formula given in Figures 3 and 4. In order to prove this qualification, it is recommended to certify personnel in accordance with EN These sections relate to the dimensions of the casting ready for assembly finish machined.
Severity level 1 is only applied to weld preparations and special rim zones. Unless other requirements have been agreed by the time of acceptance of the order, for finishing welds, the requirements for the parent metal shall apply. This assessment shall be carried out on selected casting areas which are representative of the surface finish and of the total thickness range.
The assessment areas shall have parallel surfaces. The reference echo height according to Table 2 shall be at least 6 dB above the noise signal.
If the echo height of this smallest detectable flat-bottomed or equivalent side-drilled hole diameter at the end of the test range to be assessed is less than 6 dB above the grass level, then the ultrasonic testability is reduced.
In this case, the flat-bottomed or side-drilled hole diameter which can be detected with a signal-noise ratio of at least 6 dB shall be noted in the test report and the additional procedure shall be agreed between the manufacturer and the purchaser.
NOTE For the definition of an adequate flat-bottomed hole size, the distance gain size system DGS or a test block of identical material, heat treatment condition and section thickness containing flat-bottomed holes with a diameter according to Table 2 or equivalent side-drilled holes, can be used.
Probes and transducer frequencies 5. NOTE Normal or angle probes can be used for the examination of steel castings for highly stressed components. The type of probe used depends on the geometry of the casting and the type of discontinuity to be detected. For examining zones close to the surface, twin-crystal probes normal or angle should be preferred.
The coupling medium shall wet the examination area to ensure satisfactory sound transmission. The same coupling medium shall be used for calibration and all subsequent examination operations. NOTE surfaces. The sound transmission can be checked by ensuring one or more stable backwall echoes in areas with parallel 5. The casting surfaces to be examined shall be such that satisfactory coupling with the probe can be achieved.
In special cases, specific agreements can be made. If possible, the areas to be tested shall be examined from both sides. When testing from one side only, short-range resolving probes shall be used additionally for the detection of discontinuities close to the surface. Testing with twin-crystal probes is only adequate for wall thicknesses up to 50 mm. Finishing welds which are deeper than 50 mm shall be subject to supplementary examination with other suitable angle probes.
Complete coverage of all areas specified for examination shall be conducted by carrying out systematically overlapping scans. In this case, the casting to be tested shall have parallel surfaces, the distance between which shall be measured. One of the following two techniques shall be used:? Distance-amplitude correction curve technique DAC The distance-amplitude correction curve technique makes use of the echo-heights of a series of identical reflectors flat-bottomed holes FBH or side-drilled holes SDH , each reflector having a different sound-beam path.
Distance gain size technique DGS The distance gain size technique makes use of a series of theoretically derived curves which link the soundbeam path, the apparatus gain and the diameter of a disc-shaped reflector which is perpendicular to the beam axis. When calibration blocks are used, transfer correction can be necessary. When determining the transfer correction, consideration shall be given not only to the quality of the coupling surface but also to that of the opposite surface because the opposite surface also influences the height of the backwall echo used for calibration.
If the opposite surface is machined or complies at least to the limit comparator 4 S1 or 4 S2 according to EN , this surface has a quality which is sufficient for transfer correction measurements.
If, during testing, suspicion arises that the reduction of backwall echo indication exceeds the recordable value see Table 3 , testing shall be repeated using locally reduced test sensitivity and the reduction of backwall echo indication shall be determined quantitatively in decibels.
The sensitivity setting of angle -beam probes shall be such that the typical dynamic echo pattern of these reflectors see Figure 3 is clearly visible on the screen. NOTE It is recommended that the sensitivity setting of angle-beam probes is verified on real not artificial planar discontinuities cracks with dimensions in through-wall direction or on walls perpendicular to the surface and infinite to the sound beam. In these circumstances, the probe shoe should be contured to fit the casting shape see EN The height of the echo indication is given as flat-bottomed or side-drilled hole diameter.
The backwall echo reductions to be recorded shall be marked and measured as indication areas. All echo indications from discontinuities with measurable dimensions shall be recorded, when the signal amplitude exceeds both the levels given in Table 3 and the criteria given in Figures 3 and 4.
Distinction shall be made between the different types of indications given in Table 4. To identify the type of indication, the test sensitivity can be changed according to the distance from the test surface, the geometrical shape and the surface finish of the test surface. When using transverse wave probes, irrespective of amplitude, all indications which display travelling characteristics or have an apparent dimension in through-wall direction shall be recorded for subsequent assessment according to 5.
Each location where indications to be recorded have been found, shall be marked and indicated in the test report. The location of reflection points shall be documented, e. This investigation can be achieved by altering the ultrasonic test technique e.
The ultrasonic determination of the dimensions of a discontinuity with an accuracy sufficient for engineering applications is only possible under certain preconditions e. The characterization of the type of discontinuities can be improved by using additional sound directions and angles of incidence.
For simplification of the procedure, the following categorizations of discontinuities are made:? NOTE 1 Annex B gives information on sound-beam diameters in order to distinguish between discontinuities with or without measurable dimensions. NOTE 2 Annex C gives information on types of indications and on the determination of their dimensions. It also gives information on range setting see 5.
The dimension in through-wall direction of the discontinuity should be measured according to Figure 5. Severity levela Smallest equivalent flat-bottomed or side-drilled hole diameter to be considered distance min. The severity level for special rim zones shall be specified by the purchaser. Table 2 — Ultrasonic testability requirements Dimensions in millimetres Wall thickness Tested area Smallest flat-bottomed hole diameter detectable according to 5.
The maximum distance between indications as criterion for evaluation as an individual indication or indication area in through-wall direction or lateral to the surface, shall be 10 mm.
Figure 2 — Acceptance limits for individual planar indications mainly orientated in through-wall direction see also Figures C. The maximum distance between discontinuities as criterion for evaluation as an individual indication in through-wall direction or lateral to the surface, shall be 10 mm.
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Latest version of document. Amendment dated 30 November - Correction to visibility of symbols throughout document. Their committees work with the manufacturing and service industries, government, businesses and consumers to facilitate the production of British, European and International standards. Website: www. Sample Specification Download sample specifications and see what's possible with NBS Chorus Case studies Find out how our customers use our software and services Authors Meet some of our specialists and contributors Training Interactive training courses and educational material, to help you get the most from NBS software tools Downloads and updates Download the latest versions of our software and find out about the latest updates to content About NBS Our Vision, Mission and Values Newsroom All the latest NBS and industry news and stories. Steel castings for highly stressed components Incorporating corrigendum November Steel castings for highly stressed components Incorporating corrigendum November Publication Year Document Status.