One of the less obvious changes in the recent revision of AS 2885 Part 1 was the inclusion of a requirement that almost all pipe must have a minimum toughness of 27 J, corresponding to the toughness required if API 5L PSL 2 is specified.
Clause 3.4.4 on fracture toughness was rewritten in this revision. It clarifies the toughness requirements for station pipe, linepipe and pipeline accessories. There were also some minor corresponding changes in Clause 4.8 that I won’t dwell on here.
For linepipe, Clause 18.104.22.168 now requires that if a fracture control plan is required it must specify a toughness of not less than 27 J, even if fracture control calculations would allow a lower value. There are only two conditions where the 27 J minimum does not apply, because there is no need for a fracture control plan at all:
- Pipe < DN 100 AND wall thickness < 6.1 mm AND design pressure < 10.5 MPa
- Pipe carries stable liquid with minimum design temperature > 0 deg C
The other changes in Clause 3.4.4 now provide clearer guidance on fracture control for stations and accessories.