Small Bore 316 Stainless Steel Pipe Tube 20*10mm JIS 3M Decoiling
 
 
About the magnetism of the stainless steel
 
All stainless steel is NOT necessarily non-magnetic. It is common for stainless to pick up iron ions from the die and tool used during the stamping process. Iron ions cause magnetism and later may cause minor rust. The casters you received are stainless steel even though your magnet may stick to them. We use 304 stainless to make our stainless casters. We do not use 316 stainless because it would ruin our tooling. Our customers use our stainless casters and it is very rare that there is a problem with rust unless their application is extremely caustic. If your application is extremely caustic you should require stainless steel that has gone through both the passivation and annealing processes. Passivation enhances the rust resistance of the stainless surface. The passivation process is not meant to completely restore non-magnetic property. It is only a relatively economic way to enhance corrosion resistance. It is available on special order for very large volume at substantial extra cost on some of our stainless casters. We use the passivation process standard only on stainless caster model G15. It removes all ions. Annealing is the most effective way to restore non-magnetic property and enhance corrosion resistance. However, in this process if the stainless is not heat treated high enough and then cooled down slowly the corrosion resistance of the stainless steel will be reduced. Annealing stainless is almost cost prohibitive. When both processes are applied, passivation should be done after annealing.
 
316 Stainless Steel Pipe Specification
 

 
Stainless Steel Pipe Chemical Component( %)