BS EN ISO 16946:2015 pdf free

BS EN ISO 16946:2015 pdf free.Non-destructive testing一Ultrasonic testing
BS EN ISO 16946 specifies the dimensions, material, and manufacture of a step wedge steel block for the calibration of ultrasonic instruments.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 5577, Non-destructive testing一Ultrasonic inspection一Vocabulary
EN 1330-4, Non-destructive testing一Terminology一Part 4: Terms used in ultrasonic testing
EN 10025-2, Hot rolled products of structural steels 一Part 2: Technical delivery conditions for non-alloy structural steels
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5577 and EN 1330-4 apply.
4 Dimensions
The dimensions of the block are given in Figure 1.
The tolerances are±0,1 mm for length and width of the block and -0,02 mm for the step thickness.
All external surfaces shall be machined to an Ra value not greater than 0,8 μm.
5 Alternative dimensions
In the event of a different size of calibration block being required which is not described in BS EN ISO 16946, the principles embodied in the design and manufacture of a calibration block to the requirements of this International Standard shall be applied to such a block.
The tolerances are ±0,1 mm for length and width of the block and -0,02 mm for the step thickness up to 12,5 mm and -0,1 mm for larger thickness.
6 Material
The calibration block shall be made from steel of grade S355J0 in accordance with EN 10025-2 or from equivalent steel grade.
7 Preparation
Blocks shall be rough-machined to a plan parallel plate, which is at least 3 mm larger at all sides than the dimensions of the finalised step block.
In order to obtain a fine grain structure and good homogeneity, the block shall be heat treated as follows:
a) maintain at 920℃ for 30 min;
b) rapid cooling (quenching) in water;
c) tempering by heating to 650℃ for at least3 h;
d) cooling in still air.BS EN ISO 16946 pdf download.