ISO 16811-2012 pdf free download.Non-destructive testing – Ultrasonic testing – Sensitivity and range setting.
ISO 16811 specifies the general rules for setting the timebase range and sensitivity (i. e. gain adjustment) of a manually operated ultrasonic flaw detector with A-scan display in order that reproducible measurements may be made of the location and echo height of a reflector.
It is applicable to techniques employing a single contact probe with either a single or twin transducers, but excludes the immersion technique and techniques employing more than one probe.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 2400, Non-destructive testing — Ultrasonic testing — Specification for calibration block No. I
ISO 7963, Non-destructive testing — Ultrasonic testing — Specification for calibration block No. 2
EN 12668-3, Non-destructive testing — Characterization and verification of ultrasonic examination
equipment — Part 3: Combined equipment
3 General
3.1 Quantities and symbols
A full list of the quantities and symbols used throughout this International Standard is given in Annex A.
3.2 Test objects, reference blocks and reference reflectors
Requirements for geometrical features of test objects, reference blocks and reference reflectors in general are contained in Annex B.
3.3 Categories of test objects
The requirements for range and sensitivity setting will depend on the geometrical form of the test object. Five categories of test objects are defined in Table 1.
3.4 Contouring of probes
Contouring of the probe shoe, for geometry categories 2 to 5, may be necessary to avoid probe rocking, i.e. to ensure good, uniform, acoustic contact and a constant beam angle in the test object. Contouring is only possible with probes having a hard plastic stand-off (normally twin-transducer straight beam probes or angle beam probes with wedges).
The following conditions for the different geometric categories exist (see Table 1 and Figure 1):
— category 1: No probe contouring necessary for scanning in either x- or v-direction;
categories 2 and 4: scanning in s-direction: Probe face longitudinally curved, scanning in v-direction:
Probe face transversely curved;
categories 3 and 5: scanning in either x- or v-direction: Probe face longitudinally and transversely curved.ISO 16811 pdf free download.