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Corrosion resistant stainless steel 2
- Thread starter prc
- Start date
Without knowing what is causing the corrosion, it is difficult to make a determination. However, 316 stainless is marginally more expensive (~20% more expensive) than 304 and has higher corrosion resistance. That would be where I would start. If that wasn't acceptable, 347 might be my next best guess, but it has another jump in price over 316.
MiketheEngineer
Structural
Call your vendor - they can be a wealth of info!!
EdStainless
Materials
My hunch is that the rust is superficial from the punching and handling.
Passivation after forming would eliminate this.
What is the max operating temp?
As long as it is under 600F you might look at using 2205. It is close to the same price as 316 and is much stronger and has much higher corrosion resistance.
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Plymouth Tube
Passivation after forming would eliminate this.
What is the max operating temp?
As long as it is under 600F you might look at using 2205. It is close to the same price as 316 and is much stronger and has much higher corrosion resistance.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
Guest102023
Materials
Possibly something in the filter that might be corrosive (e.g., chlorides)? That could cause something resembling corrosion under insulation. Think of the paper products industry as one giant disposal method for small contaminants of all sorts.
You need to define the environment and the form of corrosion better before considering a material upgrade. There is not usually a silver bullet solution to corrosion, and sometimes less is more (man am I thick with clichés today).
You need to define the environment and the form of corrosion better before considering a material upgrade. There is not usually a silver bullet solution to corrosion, and sometimes less is more (man am I thick with clichés today).
- Thread starter
- #8
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- #9
EdStainless
Materials
Could be a lot of things.
The rust around the fasteners makes me suspect that they are plain steel.
Does it clean off? Use a flap wheel and see what it looks like underneath. If there isn't any pitting then it is all superficial and should clean up.
No, passivation isn't hard. Warm nitric acid for an hour, or hot citric acid for 12 hours.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
The rust around the fasteners makes me suspect that they are plain steel.
Does it clean off? Use a flap wheel and see what it looks like underneath. If there isn't any pitting then it is all superficial and should clean up.
No, passivation isn't hard. Warm nitric acid for an hour, or hot citric acid for 12 hours.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
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btrueblood
Mechanical
In addition to what Ed said: the corrosion along the bend line looks like some iron embedment from the bending press/brake; this will likely improve by pickling/passivating as Ed suggests.
I agree that the problem is most likely iron contamination during the forming processes. You may not need to go to a pickling process however. I would first try an aggressive sand blast. We have had good success with a crushed garnet blast on stainless steel castings.
Bob
Bob
You clearly have a contamination issue. Do you interchange materials (carbon and low alloy with stainless steel) on the same processing equipment? If so, how do you clean the equipment between processing of carbon steels and stainless steels? Develop appropriate protection/cleaning procedures for materials changes.
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