Water Quality for Hydrotesting
Water Quality for Hydrotesting
(OP)
All,
I have been tasked with meeting a specification for hydrotest water purity that seems a little "stringent". Usually DI water was sufficient at other sites, however, now I have a new specification to meet with water purity as follows:
Chlorides 50 ppm max (SS) 100 ppm max (CS)
pH 6.5-9
Sulfate 42 ppm
Fatty Acids 14 ppm
Ammonium 3 ppm (max)
Bacteria(SRB ,APB ,etc.) insignificant or "very low" activity
Total Suspended Solids 30 ppm
Turbidity <1 Nephelometric Turbidity Unit
Total Organic Compound 4 ppm
Temperature < 120°F
I have exhausted my resources trying to find a lab that can test for "all" of the list and can't seem to find a vendor who can deliver water "pre-tested" and certified to meet all of the requirements above. I am reaching out to anyone with water purity experience for advice, vendors, etc. that can aid in what I am trying to meet. (Keep in mind, I am a mechanical guy and not a chemist), so any comments are welcome.
I have been tasked with meeting a specification for hydrotest water purity that seems a little "stringent". Usually DI water was sufficient at other sites, however, now I have a new specification to meet with water purity as follows:
Chlorides 50 ppm max (SS) 100 ppm max (CS)
pH 6.5-9
Sulfate 42 ppm
Fatty Acids 14 ppm
Ammonium 3 ppm (max)
Bacteria(SRB ,APB ,etc.) insignificant or "very low" activity
Total Suspended Solids 30 ppm
Turbidity <1 Nephelometric Turbidity Unit
Total Organic Compound 4 ppm
Temperature < 120°F
I have exhausted my resources trying to find a lab that can test for "all" of the list and can't seem to find a vendor who can deliver water "pre-tested" and certified to meet all of the requirements above. I am reaching out to anyone with water purity experience for advice, vendors, etc. that can aid in what I am trying to meet. (Keep in mind, I am a mechanical guy and not a chemist), so any comments are welcome.
RE: Water Quality for Hydrotesting
For CS drinking water is ok.
RE: Water Quality for Hydrotesting
RE: Water Quality for Hydrotesting
What sort of volume are you looking at?
Can't you just sample the mains water?
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Water Quality for Hydrotesting
RE: Water Quality for Hydrotesting
Or you need to get some sort of UV steriliser to get rid of the bacteria etc.
Can you realistically save lots of the test water and then filter it and test it on regular basis in a storage tank?
All looks a bit OTT to me.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Water Quality for Hydrotesting
RE: Water Quality for Hydrotesting
There are people there who are much more "water based"
Add how much you need and where you are based otherwise you'll just get asked that question...
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Water Quality for Hydrotesting
RE: Water Quality for Hydrotesting
And just copy and paste in the address.
And I said the water forum, but the chemical process one....
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Water Quality for Hydrotesting
Keep your fingers crossed if this gets you a hydro-test waiver.
DHURJATI SEN
Kolkata, India
RE: Water Quality for Hydrotesting
That's what change orders are for.
RE: Water Quality for Hydrotesting
Alternatively, you may present the water quality from your shop used for "successfully" testing the pipes in the pass.
RE: Water Quality for Hydrotesting
Regards
RE: Water Quality for Hydrotesting
The use of salt or brackish water should be avoided.
Test water should be free from sediment and corrosive substances.
The test water should be verified to be free of microbes. If the water contains an unacceptable level of microbes, it should be disinfected.
Test water used for austenitic steel vessels or piping systems, or for components clad or overlaid with austenitic stainless steel, should be condensate, demineralized, or of potable quality, with a verified chloride content of less than 50 ppm.
Test liquid should be drained immediately after completion of the hydrostatic test.
Care should be exercised to provide proper venting to prevent the creation of internal negative pressure (vacuum) during draining.
Pressure vessels and/or piping systems that will hold the test water for more than 10 days, whether or not the test liquid is pressurized, should be treated with a corrosion inhibitor and biocide.
A corrosion engineer should be consulted.
If further drying is necessary, the use of hot air or hot nitrogen should be considered.
If complete drainage of austenitic stainless steel vessels and/or piping systems is not possible, the components should be flushed with low-chloride (less than 5 ppm)
Regards
luis
RE: Water Quality for Hydrotesting
Requires a large exclusion zone but as long as scheduling is planned well there is very little impact on production downtime.
RE: Water Quality for Hydrotesting
fatty acids and sulphate sounds like waste water to me.
Perhaps suggest other fluids - one listed seem to be propylene glycol, potassium acetate, methanol (not one on my list tbh) or this stuff someone else makes..
https://www.novamen.ca/products/hydro-testing-prod...
Probably costs multiples what the water does, but if it gets you out of the holes you're in then??
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Water Quality for Hydrotesting
Regards
RE: Water Quality for Hydrotesting
The welds that formed leaks are associated with an RO water service that is intermittently used. It can remain stagnant for up to 6 months before flow is established in the line. The lab concluded that one of the damage mechanisms were due to MIC and the other was due to Chloride stress corrosion cracking. The welds in question are 316 ss, sch. 10, and less than 3 years in age. I do not believe the welding is the issue in this instance.
RE: Water Quality for Hydrotesting
My opinion only.
Regards
RE: Water Quality for Hydrotesting
RE: Water Quality for Hydrotesting
RE: Water Quality for Hydrotesting
[indent][/You ask very good questions. I am not an operator and really do not have an answer as to why they leave the water stagnant for so long within the pipe. The water is, however, allegedly de-ionized water that should be very low on all counts (chlorides, TSS, ETC.). I really have no explanation as to why deionized water would have these types of issues other than leaving any type of moisture, in a stagnant phase over a period of time would create such issues. I may be way off base, however I am at as much of a loss on the reason for the detected damage mechanisms as I am with the water quality requirements.