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corrosion reason
- Thread starter wwtp2014
- Start date
RO- reverse osmosis? PHE- Plate Heat Exchanger made from what? Put more details of the corrosion to increase chances of good answer.
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- #3
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EdStainless
Materials
What are you using as cleaning chemicals?
Are the leaks at welds? Are they usually in the bottoms of tubes?
Does this plant run at full capacity 24 hrs/day?
Many food product plants run with all 316 tubing for 40 years without any leaks.
It requires high quality tubing (not just ASTM), proper installation and commissioning, and proper operations and maintenance.
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P.E. Metallurgy, Plymouth Tube
Are the leaks at welds? Are they usually in the bottoms of tubes?
Does this plant run at full capacity 24 hrs/day?
Many food product plants run with all 316 tubing for 40 years without any leaks.
It requires high quality tubing (not just ASTM), proper installation and commissioning, and proper operations and maintenance.
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
- Thread starter
- #6
What are you using as cleaning chemicals? Nitric acid 68% and NaOH 40-45%
Are the leaks at welds? Are they usually in the bottoms of tubes? the leaks at welds and at the pipe itself and the leaks everywhere bottom, top and sides
Does this plant run at full capacity 24 hrs/day? Yes
What about water specification and what is the suitable Total Hardness for Stainless steel 316 and 304
Are the leaks at welds? Are they usually in the bottoms of tubes? the leaks at welds and at the pipe itself and the leaks everywhere bottom, top and sides
Does this plant run at full capacity 24 hrs/day? Yes
What about water specification and what is the suitable Total Hardness for Stainless steel 316 and 304
EdStainless
Materials
There are only a few things that will attack 316.
The chief among them in chlorides. What is the chloride (as in salts, not chlorine) content of your water?
What temperatures do you run?
Once pitting and crevice corrosion have started there is no stopping them. You will need to replace the system.
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P.E. Metallurgy, Plymouth Tube
The chief among them in chlorides. What is the chloride (as in salts, not chlorine) content of your water?
What temperatures do you run?
Once pitting and crevice corrosion have started there is no stopping them. You will need to replace the system.
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
You might want to review the attached publication regarding diary piping design and installation. It sounds to me like original problems with welding issues and handling of the pipe itself during installation.
- Thread starter
- #10
EdStainless
Materials
pH and Cl are the most critical.
But if the tubing was not well shielded when welded, and thoroughly cleaned (nitric acid passivated) before being put into service then you will have problems for sure.
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P.E. Metallurgy, Plymouth Tube
But if the tubing was not well shielded when welded, and thoroughly cleaned (nitric acid passivated) before being put into service then you will have problems for sure.
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
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