Introducing the new European standard on delivery conditions for hot-finished hollow steel
Published: October 2020
We’ve now published the third in a series of European standards on hot-finished hollow section structural steel. This blog post explains the genesis of Part 3 and what’s covered.
For a bit of background, Part 1 of this short series of European standards is BS EN 10210-1, Hot finished steel structural hollow sections — Part 1: Technical delivery conditions. This was published in 2006 in the Official Journal of the European Union (OJEU) under the Construction Products Regulation (CPR Regulation (EU) No. 305/2011). It therefore allows the CE marking of all the products included in it.
The European technical committee responsible for the series subsequently tried to revise BS EN 10210-1:2006. They wanted to extend its scope to include not only higher-strength steel grades and weather-resistant steels, but also other new processes that they were aware of. These included thermomechanical forming and quenched and tempered steels. However, this didn’t work out due to difficulties encountered in making it comply with the EU Regulation, so the draft revision was never published as a standard.
At that point, the committee decided to incorporate the proposed additions to Part 1 into a new Part 3. Note that this Part 3 is not under the Construction Products Regulation. This new specification is therefore a voluntary standard that can be used if the covered products are to be used in mechanical engineering applications. It will not be possible to CE mark them under the CPR however. So what exactly is covered in the new standard?
Technical delivery conditions
BS EN 10210-3:2020 Hot finished structural steel hollow sections - Part 3: Technical delivery conditions for high strength and weather resistant steels specifies technical delivery conditions for high strength and weather resistant hot-finished seamless, electric welded and submerged arc welded steel structural hollow sections of circular, square, rectangular or elliptical forms.
It applies to hollow sections formed hot, with or without subsequent heat treatment, or formed cold with subsequent heat treatment above 580°C to obtain equivalent mechanical properties to those obtained in the hot formed product.
Note that the requirements for tolerances, dimensions and sectional properties are covered in Part 2. Also a range of material grades is specified in the standard, and the user can select the grade most appropriate to the intended use and service conditions.
The grades and mechanical properties of the finished hollow sections are generally comparable with those in BS EN 10025-4, BS EN 10025-5 and BS EN 10025-6.
Terms, definitions and symbols
The standard begins by covering terms, definitions and symbols. It then covers the classification and designation of steel names. The following section covers the information to be obtained by the manufacturer. This includes mandatory information and a list of options. It also gives an example of an order.
The standard then specifies the manufacturing process, including grain structure and delivery condition. The next, highly detailed section deals with requirements. It includes chemical composition, mechanical and technological properties and non-destructive testing.
Section 8 covers inspection, while Section 9 describes frequency of testing and preparation of samples; and Section 10 sets out test methods. The final section is on marking and this is followed by seven informative annexes on the chemical composition and mechanical properties of different types of steel.
All told, this is designed to be a standard that will be valuable to a range of users, including structural steel manufacturers, fabricators, stockholders and distributors, as well as structural steel testing and assessment providers, and relevant Notified Bodies under the EU Construction Products Regulation.