BS EN ISO 2566-1:2021

What is ISO 2566‑1 - Conversion of elongation values for steel about?   

With specifications stipulating minimum percentage elongations on different gauge lengths of steel, test results need to be converted into values based on the different gauge lengths. ISO 2566‑1 addresses this need for conversion of elongation values. 

ISO 2566‑1 is the first part of the multi-series and specifies a method of converting room temperature percentage elongations after fracture obtained on various proportional and non-proportional gauge lengths to other gauge lengths. 

Formula (1), on which conversions are based, is reliable when applied to carbon, carbon-manganese, molybdenum, and chromium-molybdenum steels within the tensile strength range of 300 N/mm2 to 700 N/mm2 and in the hot-rolled, hot-rolled and normalized or annealed conditions, with or without tempering. 

Note 1: These conversions are not applicable to: 

• Cold reduced steels 
• Quenched and tempered steels 
• Austenitic steels 

Note 2: These conversions are not applicable when the gauge length exceeds 25S0 or when the width to thickness ratio of the test piece exceeds 20. 

Who is ISO 2566‑1 - Conversion of elongation values for steel for?  

ISO 2566‑1 on the conversion of elongation values for steel is useful for:  

• The metals industry  
• The machinery and metal products industry  
• The construction industry   
• Manufacturers and suppliers of steel  

• Manufacturers of steel products  
• Product development/innovation teams  
• Quality control/testing personnel  
• Procurement teams  
• Agencies involved in carbon and low-alloy steels 

Why should you use ISO 2566‑1 - Conversion of elongation values for steel?   

Several different gauge lengths are commonly in use for the determination of the percentage elongation of steels in tensile testing. Fixed gauge lengths of 50 mm, 80 mm, 100 mm, and 200 mm are used; proportional gauge lengths of kS0 are also used for flat and round test pieces, where k may be one of several values, i.e., 4; 5,65; 8,16 or 11,3. 

To address this, ISO 2566‑1 includes tables of conversion factors, tables of actual conversions for some of the most used gauge lengths and elongation values, and figures which may also be used for such conversions. 

Detailed formulae and tables have been provided in ISO 2566‑1 to illustrate the calculations and dimensions of steels. 

The tensile testing method in ISO 2566‑1 can serve as a guide to testing agencies, industries, and manufacturers of products. ISO 2566‑1 serves as a procurement guide that enables clear communication between users and suppliers so that users have access to high-quality steel products.   

What’s changed since the last update?  

BS EN ISO 2566‑1:2021 supersedes BS EN ISO 2566-1:1999, which is withdrawn. BS EN ISO 2566‑1:2021 includes some technical and editorial changes with respect to BS EN ISO 2566-1:1999. These include:  

• Complete editorial revision 
• Tables 2 to 5 have been renamed due to reordering in order to follow the logical flow of information in ISO 2566‑1 
• Clause 9 has been restructured into four sub-clauses in order to follow the logical flow of information in ISO 2566‑1