BS EN ISO 11666:2018

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Determination of discontinuity length
5 Sensitivity setting and levels
6 Acceptance levels
Annex A (normative) - Level
Annex B (normative) - Fixed-amplitude level technique

Describes two ultrasonic acceptance levels known as acceptance level 2 (AL 2) and acceptance level 3 (AL 3) for full penetration welded joints in ferritic steels, which correspond to ISO 5817:2014, quality levels B and C.

This document specifies two ultrasonic acceptance levels known as acceptance level2 (AL2) and acceptance level3 (AL3) for full penetration welded joints in ferritic steels, which correspond to ISO5817:2014, quality levelsB and C. An acceptance level corresponding to ISO5817:2014, quality levelD is not included in this document, as ultrasonic testing is generally not requested for this weld quality.

These acceptance levels are applicable to testing carried out in accordance with ISO17640.

This document applies to the testing of full penetration ferritic steel welds, with thicknesses from 8mm to 100mm. It can also be used for other types of welds, materials and thicknesses, provided the tests have been performed with necessary consideration of the geometry and acoustic properties of the component, and an adequate sensitivity can be employed to enable the acceptance levels of this document to be applied. The nominal frequency of probes used in this document is between 2MHz and 5MHz, unless attenuation or requirements for higher resolution call for other frequencies. It is important to consider the use of these acceptance levels in conjunction with frequencies outside this range carefully.