can some of you experienced individ
can some of you experienced individ
(OP)
can some of you experienced individuals shine some light on following issue please?
what is pH and chloride content requirement, if any by (ASME/API) for flushing(not hydrotesting) the Aust SS pipe for new installation? lot of search comes with requirement pertaining to hydrotest but not much for flushing. I really appreciate you taking time to respond.
what is pH and chloride content requirement, if any by (ASME/API) for flushing(not hydrotesting) the Aust SS pipe for new installation? lot of search comes with requirement pertaining to hydrotest but not much for flushing. I really appreciate you taking time to respond.





RE: can some of you experienced individ
RE: can some of you experienced individ
Stl Stl doesn't like chlorides in any form and it is best avoided.
Can't see hay anything different from hydrotest wouldn't apply.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: can some of you experienced individ
RE: can some of you experienced individ
And no, we never use seawater to hydro on pipe spool at the fab shop. no hydro has ever performed at site to date, not there yet.
RE: can some of you experienced individ
Since 200 mg/L (304SS), 2,000 mg/L (316SS) and 5,000 mg/L (904LSS) chloride levels are acceptable for avoiding pitting & crevice corrosion are for extended use in critical service, use of water somewhat above these levels should not cause problems at the short times used in hydrotesting and flushing. Obviously, this requires the hydrotesting and flushing times to be kept short, and the equipment to be drained and dried after hydrotesting and flushing.
Disinfection of the water is also essential to remove the risk of MIC. Disinfection can be carried out by a variety of methods, some of which also carry risks of making the water more aggressive for other forms of corrosion. Potable water from properly conditioned municipal supplies do not generally require further disinfection. Potable waters seldom have more than 100 mg/L of chlorides.
Refer to the attachment.
http://www.stainless-steel-world.net/pdf/11003.pdf
API 570: Piping & Inspection Code, American Petroleum Institute.
Piping fabricated of or having components of 300 series stainless steel should be hydrotested with a solution made up of potable water (see note) or steam condensate. After testing is completed, the piping should be thoroughly drained (all high-point vents should be opened during draining), air blown, or otherwise dried. If potable water is not available or if immediate draining and drying is not possible, water having a very low chloride level, higher pH (>10), and an inhibitor addition may be considered to reduce the risk of pitting and Microbiologically Induced Corrosion (MIC).
Note: Potable = ‘suitable for drinking’. Potable water in this context follows US practice, with 250 ppm maximum chloride, sanitized with chlorine or ozone.
RE: can some of you experienced individ
RE: can some of you experienced individ
RE: can some of you experienced individ
RE: can some of you experienced individ
And today finding 304 pipe that will survive long in 100ppm is a gamble.
I would like see potable water used, <50ppm Cl, pH above 7 (stainless does not care if it is 10), and a biocide added.
MIC will destroy a pipe in a few days once it starts growing.
George is also correct in pointing out that unless the line is going straight into service you need to drain and dry it. Standing pools or water invite both Cl pitting and MIC. If a 1l puddle evaporates to 10ml the Cl content has just gone up 100x.
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P.E. Metallurgy, Plymouth Tube