With the release of the new NS-EN 1090-2 in September 2018, the version NS-EN 1090-2:2011 will be replaced.
These are extracts of some important points that affect welding:
Welding of reinforcement has been included in the revised NS-EN 1090-2:2018. This refers to two standards
- NS-EN ISO 17660-1 (load-bearing welded joints)
- NS-EN ISO 17660-2 (non-load-bearing welded joints)
The standards are valid for welding work in workshops and on construction sites, and include both weldable "black" reinforcing steel and stainless steel reinforcement. Unlike welding of steel structures, welds connecting reinforcing steel to each other or to other steel components are not dimensioned, but must be performed according to the instructions and drawings in NS EN ISO 17660. The prerequisite is that the reinforcing steel is weldable. Comb steel B500NC according to NS 3576-3 is weldable.
Load-bearing welds of reinforcing steel and of reinforcing steel to structural steel shall be specified as any other component of the production substrate according to NS-EN 1090-2 2018 chapter 4.2.2.2. NS-EN 1090-2:2018 chapter 4.2.2
The reason for these stringent welding requirements is that the heat treatment of the reinforcement easily changes and reduces the mechanical properties of the steel.
Welding procedure specifications may be required for EXC1!
Welding plan content, new requirements:
Unless otherwise specified, welding on cold-formed zone shall be carried out in accordance with the conditions given in EN 1993-1-8:2005 chapter 4.14.
Welding may be carried out within a length of 5 h on each side of the cold-formed zone, see table 4.2, provided that one of the following conditions is met:
Cold formed zones are normalized after cold forming and before welding;
the r/t ratio meets the limit value given in table 4.2.
New point: Extended requirement for monitoring of heat input at short weld lengths.
Approval of welding procedure, new requirements:
Table 12 has significant changes, this needs to be revisited.
Comment: The standard welding procedure according to EN ISO 15612 was previously only allowed for materials ≤ S355 in EXC2 and only for manual or partially mechanized welding and not in EXC3 and EXC4.
Now, in EXC2 it is no longer limited by the strength (Notes a and b have been removed from table 12.), and in EXC3 and EXC4 it is allowed if specified in the production documentation.
There is a new edition of EN ISO 15612:2018
For stainless steel, EN ISO 15614-1 shall be used, without some exceptions. See NS-EN 1090-2:2018.
Validity of a welding procedure approval
New: The limitation of the lifetime of an approved welding procedure has been removed. This means that the requirement for additional tests for an approved welding procedure in accordance with NS-EN ISO 15614-1 that has been carried out for a welding method that has not been used has now been removed. Production tests must be carried out if specified.
