303/304 Stainless Steel, Comparison
303/304 Stainless Steel, Comparison
(OP)
For use in bulk materials handling machines we have traditionally made some special bolts in 304 to resist corrosion in general (as opposed to the normal mild steel ones).
We are considering changing to 303 as our machine shop advise they can machine this quicker so reducing the cost. However, a collegue has noted that 303 is more susceptable to pitting corrosion than 304 and maybe we should stay with 304. Personally I think that there will not be a problem as other platework parts are made in 1.4003 (3CR12) and do not suffer problems.
Is the greater susceptability of 303 over 304 significant, anyone care to comment?
Bulk materials handled include wet coal, wet filter cake (delightfully vague!), steeped barley, green malt.
We are considering changing to 303 as our machine shop advise they can machine this quicker so reducing the cost. However, a collegue has noted that 303 is more susceptable to pitting corrosion than 304 and maybe we should stay with 304. Personally I think that there will not be a problem as other platework parts are made in 1.4003 (3CR12) and do not suffer problems.
Is the greater susceptability of 303 over 304 significant, anyone care to comment?
Bulk materials handled include wet coal, wet filter cake (delightfully vague!), steeped barley, green malt.





RE: 303/304 Stainless Steel, Comparison
RE: 303/304 Stainless Steel, Comparison
Maybe you find roll threaded bolts in a high Cr ferritic grade like 18-2. These should cost less and still offer better corrosion resistance than your system.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: 303/304 Stainless Steel, Comparison
These are in fact a purpose designed shouldered bolt so we are going to have to make them ourselves. I don't believe the corrosive conditions are that bad, but I take your point about poor toughness and fatigue strength.
Any suggestions about a suitable steel available in bar that would be easily machinable yet corrosion resistant?
RE: 303/304 Stainless Steel, Comparison
My suggestion would be to look at duplex stainless grades. Focus on the lean alloys such as 2304, LDX2101 and AL2003. They don't machine badly, better than 304.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: 303/304 Stainless Steel, Comparison
RE: 303/304 Stainless Steel, Comparison
We're actually using a sub-contract maching company and I know the guy in charge of production (we worked together way back) and it was his suggestion to use 303 to reduce the cost of the item.
RE: 303/304 Stainless Steel, Comparison
303 isn't 304, but it isn't PlayDough either! Plenty of stressed parts are made from 303 and are found to be quite serviceable- including parts with threads cut into them. It doesn't sound like a very tough corrosion service either. Are we sure we're not steering the OP away from 303 unnecessarily? There certainly would be a fabrication efficiency/cost benefit for using 303 vs other materials, especially if these small lot-order parts are being churned out of bar on a CNC machine.
RE: 303/304 Stainless Steel, Comparison
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm