There are different types of stainless steel that are used in various industrial applications. Here we discuss some of the most common types of stainless steel.
The 300 series of stainless steel is made up of 8% nickel and 18% chromium. The term 18-8 can be used interchangeably to refer to several characterize fittings that are available in 302, 303, 304, 305 and other varieties of the same grade with adjacent chemical composition. There is minimal difference in terms of resistance to corrosion among these types, but the difference can result in some types being more resistant to different chemicals and atmosphere. Such materials can be used to make the top stainless-steel tube. In addition, these types of stainless steel have better corrosion resistance to the 400 series as they are usually nonmagnetic. They can also be hardened through cold working.
The 304 Series
This is the primary alloy among type 18-8. They are austenitic steel containing a minimum of 18% chromium, 8% nickel coupled with 0.08% carbon. They can also be used to manufacture the top stainless steel tube since they are nonmagnetic and can’t be hardened by treatment or heat. However, you can resort to cold working if you wish to obtain better tensile strength.
The 18% chromium is essential in protecting against oxidation and corrosion. The alloy has metallurgical qualities provided by the 8% nickel content. The nickel content is useful in providing additional protection from corrosion caused by reducing agents. Carbon is also valuable for proving additional strengthen and it is kept at a maximum of 0.08%, which is needed for many industrial applications.
Other Important Characteristics
Alloys of stainless steel have the capability of withstanding the effect of oxidizing acids as well as rusting. However, it can tarnish. It is also immune to sterilizing solutions, organic chemicals, foodstuff, and dyestuff. It can also resist the effect of numerous inorganic chemicals. Type 304 is the most common and most preferred variety due to its modification. It is also the most recommended whenever there is a need for stainless steel.
Common Uses of Type 304
Manufacture of Kitchenware
Type 304 has a wide range of uses due to its ability to resist the corrosive effect of some chemicals. For instance, it can withstand the impact of corrosive acids found in various fruits, milk, vegetables, and meats. It is, therefore, suitable to make kitchenware including sinks, coffee jugs, milk dispensers, tablespoons, refrigerators, and stoves. It is also preferred in the manufacturing of kitchen utensils, including cooking appliances such as pans, flatware and pots.
Type 304 is also suitable for the manufacture of dairy equipment such as sterilizers, milking machines, homogenizers, and containers. It can also be used to make additional milking components such as piping, milk trucks, valves, railroad cars and storage and hauling tanks.
It is also suitable in the brewing industry where it can be used to make yeast pans, storage cars, fermentation vessels, and piping. The alloy is also useful in the juice industry where it can be used to manufacture crushing, storage, preparation and hauling facilities.
Food Processing Industry
Most metal equipment that is used in the manufacture of animal and vegetable oil is made from type 304. The alloy is also utilized in the food processing industry, especially in applications such as slaughter, mills, packing houses and bakeries.
Type 304 is used in the dyeing industry to make dye tanks, dippers and pipeline buckets. It is also useful in manufacturing several components in the dyeing industry, especially the ones exposed to organic acids and acetic.
The marine environment requires a slightly better strength and wear resistance that can be offered by type 316. That is why type 304 is used to make fasteners such as screws, bolts, and nuts among others. The alloy is also useful in the manufacture of cogs as well as other components that operate in an environment that needs wear and corrosion-resistant material.
There are other industrial applications that require a high level of resistance to corrosion than that offered by type 304. This is where type 316 comes in. It contains most of the characteristics of type 304 such as non-magnetism, austenitic, and thermally nonhardenable but on a higher degree compared to type 304. It contains carbon content maintained at a maximum of 0.08%. The only difference between type 316 and 304 is the additional molybdenum maintained at a maximum of 3%.
The benefit of molybdenum is that it improves the corrosion resistance characteristics sustained by an alloy of chromium and nickel. This makes it better at withstanding the effect of numerous industrial chemicals and solvents, especially the inhibits pitting resulting from chlorides. Type 316 can also resist the corrosive effect caused by brines of sodium and chloride, phosphoric acid and hypochlorite solutions. Type 316 is also the primary alloy used in the marine industry apart from fasteners.