BS ISO 19835:2018 pdf download

BS ISO 19835:2018 pdf download.Non-destructive testing — Acoustic emission testing — Steel structures of overhead travelling cranes and portal bridge cranes
1 Scope
This document describes the acoustic emission (AE) testing technique used to perform structural integrity evaluation on steel structures of overhead travelling cranes and portal bridge cranes. This document applies to the testing of steel structures of in-service overhead travelling cranes and portal bridge cranes. Testing of other kinds of cranes can refer this document. This testing method is not intended to be an alone NDT standard method for the evaluation of the structural integrity of overhead travelling cranes and portal bridge cranes. Other NDT methods are used to verify and supplement the AT results. This document does not establish evaluation criteria.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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 4310, Cranes — Test code and procedure
ISO 12714, Non-destructive testing — Acoustic emission inspection — Secondary calibration of acoustic emission sensors
ISO 12716, Non-destructive testing — Acoustic emission inspection — Vocabulary
ISO/TR 13115, Non-destructive testing — Methods for absolute calibration of acoustic emission transducers by the reciprocity technique
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12716 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1 acoustic emission source
AE source
source point or spatial position in the material where transient elastic waves are generated by the release of energy
6.2 AE sensors
It is recommended to use sensors in the frequency range between 100 kHz and 400 kHz. The minimum sensitivity shall be equivalent or greater than 60 dB referred to 1 V/(m∙s-1) in surface wave sound field calibration, or in longitudinal wave calibration. When sensors with other response frequencies are used, they shall provide enough sensitivity within its frequency band. Sensors shall be shielded against radio frequency and electromagnetic noise interference by proper shielding practice or by differential element design, or both. The metallic case of each AE sensor shall be electrically isolated from a metallic test object. The AE sensors shall be stable over the response frequency and temperature range of use, and shall not exhibit sensitivity changes greater than 3 dB over this range. AE sensors mounted on the surface of a steel structure shall be insulation from each other. For sufficient sensitivity, a pencil lead break of 0,5 mm diameter, hardness 2H, in 50 mm distance from the sensor, shall generate an amplitude of at least 95 dB AE . The calibration of the sensors shall be performed according to ISO 12714 or with ISO/TR 13115.