SS material grade selection for Deionized water tank
SS material grade selection for Deionized water tank
(OP)
We need to design and construct a stainless steel water tank for our customer of 125,000 gallons capacity.
a) What grade is normally used for SS tank construction?
b) Is using the stabilized grades such as 304L or 316L preferred than 304 or 316?
c) What is the advantage in using 316L over 304L and will there be a huge price impact?
a) What grade is normally used for SS tank construction?
b) Is using the stabilized grades such as 304L or 316L preferred than 304 or 316?
c) What is the advantage in using 316L over 304L and will there be a huge price impact?





RE: SS material grade selection for Deionized water tank
With stainless you need to take the quality of the DI into account because lower grade stainless will leach far worse in high quality DI. Also consider Teflon coating for high purity applications.
RE: SS material grade selection for Deionized water tank
"You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein
RE: SS material grade selection for Deionized water tank
The cleaner the water the better the alloy that you need. A small amount of air and CO2 in high purity water will attack many alloys.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
RE: SS material grade selection for Deionized water tank
For this DI tank when we approached tank fabricators we are told that Grade 304L will be good enough. I do not agree totally with the tankie as it may be OK from a cost perspective. Any thoughts??
RE: SS material grade selection for Deionized water tank
It comes down to price, for the SS and for the fab. 304L is pretty weak, especially low yield strength which is of major importance. You could probably use thinner gauge with a newer alloy--it all has to be priced out.
Watch for MIC after you first fill the tank, esp. if DI water isn't used vfor a hydrotest. Do not let non-DI water remain in the tank for more than a very few days.
"You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein
RE: SS material grade selection for Deionized water tank
RE: SS material grade selection for Deionized water tank
I presume that the system is designed to exclude air, and sealed against microbiological contamination.
I also presume that you have a good cleaning and passivation practice to follow.
Seriously look at LDX2101. The tanks that I worked with were large than this but the weight of metal was reduced by 45% over 304L/316L. Lighter material welds faster and uses less filler. The material is slightly more difficult to form because of its strength but the total fab cost didn't go up and the metal cost went down a lot.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
RE: SS material grade selection for Deionized water tank
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube