Performance comparison
316 and 316L stainless steels contain element of Mo. The content of Mo in 316L is slightly higher that in stainless steel 316. Due to the adding of element of Mo, the overall performance of SS316 and SS316L under high temperature conditions is better than SS310 and SS304, also when the concentration of sulfuric acid is below 15 percent or above 85 percent , 316 stainless steel has a wide range of applications. 316 stainless steel also has good performance against chloride corrosion, so it is usually used in marine environment. The maximum carbon content of 316L is 0.03, which can be used on material unable to be annealed after welding or it requires maximum corrosion resistance.
Corrosion resistance comparison
The corrosion resistance of 316 stainless steel is better than that of 304 stainless steel.
It has good corrosion resistance in the production of pulp paper making. And 316 stainless
Steel is also resistant to erosion by marine or aggressive industrial atmospheres.
Generally speaking, for chemical corrosion resistance, 304 stainless steel and 316 stainless steel have similar performance, just different from some specific media.
The firstly developed stainless steel was 304, while this material is more sensitive to pitting corrosion in a certain case. So, the additional 2-3 percent Mo reduces this sensitivity, thus giving birth to stainless steel 316, in addition to that, this extra content of Mo can also reduce the corrosion of some hot organic acid eclipse.
Nowadays, 316 stainless steel has almost become the standard material in food and beverage industry. Due to the shortage of Mo element in the world and more engagement of element Ni, 316 stainless steel is much more expensive than 304 stainless steel.
Pitting corrosion is a phenomenon mainly caused by deposition corrosion on the surface of stainless steel, which is due to lack of oxygen and can not form a protective oxide layer.
Especially in small valves, the possibility of deposits on the valve plate is very small,
Therefore, pitting corrosion also rarely occurs.
In various types of water media (steam storage water, drinking water, river water, boiler
Corrosion resistance of 304 stainless steel and 316 stainless steel is almost the same, except that the content of chloride ions in the medium is very high, which 316 stainless steel is more suitable.
Corrosion resistance of 304 stainless steel vs. 316 stainless steel in most cases has not much difference, but in some specific cases it can be very different, it depends on the actual circumstances. Generally speaking, valve users should know how to choose suitable material for their contains and pipes according to actual circumstances, so it is not recommended to decide materials for the users.
heat resistance
Intermittent use below 1600 degrees or continuous use below 1700 degrees, 316 stainless steel has good oxidation resistance. While between the temperature of 800-1575 degree, it is better not use SS316 continuously, for the temperature beyond this range, stainless steel has good temperature resistance. The performance ratio of carbide precipitation resistance of 316L stainless steel is better than 316 stainless steel and can be appliable for these temperature scope.
Heat treatment:
Annealed in the temperature range of 1850-2050 degrees, then quickly retreated
fire, and make it cool quickly, 316 stainless steel cannot be hardened by overheating.
welding
316 stainless steel has good welding ability. All standard welding methods can be applied, according to different application, we can use 3160b. 316L or 309cb stainless steel filler rod or electrode for welding. In order to get the best corrosion resistance of SS316, annealing is required for welding sections after welding, while if using 316L stainless steel, annealing is not required after welding.
