@DekDee - the technique under discussion is tangential. The 115 mm comes from the formula in ISO 20769-1, i.e along the pipe wall, as opposed to straight through.
The penetrated thickness is around 115 mm. For Se75, ISO 20769-1 recommends a maximum penetrated thickness of 55 mm for a basic technique, and 40 mm for an enhanced technique. Digital techniques may extend the recommended penetrated thickness. As to whether such techniques could give the...
Their rules. Their problem if it doesn't work out.
I'm not really a downstream afficionado, but I would get Technical Safety involved as to their view on relying upon an operating procedure to create inherently safe conditions versus picking a material with resistance to the failure mode.
Is it not recommended to work on the max operating conditions.
Until the process safety system settings are finalised, the max operating conditions will be guesswork too. It will also depend on the risk tolerance of the assessment in terms of the expectation of how rapidly the damage mechanism...
NACE/ISO is for types of stress cracking only - it does not deal with pitting or crevice corrosion. I have seen equipment that has been in non-sour service with 100+k ppm of chloride having no untoward effects, and I’ve seen equipment with very much less chloride having major issues. It’s the...
You are attempting to perform a corrosion risk assessment based on simulations and assumptions (most likely of normal operating conditions). What is your precise issue: keeping the cost down by not specifying sour service? Look at all possible process scenarios, the possible progression speed...
What specification are they working to, ISO 24139-1 ? The service you are supplying is just the heat treatment? The PBHT should be part of the manufacturing procedure qualification, so someone should be cutting up a test bend to ascertain the properties. At the very least, the CRA will need...
