SCH40 / SCH80 Stainless Steel Pipe Nipple304 316 3/4"X4" NPT ASTM A312

304 stainless steel has a high resistance to rust. It withstands corrosion from
most oxidizing acids and is often used for kitchen and food applications.
However, it is susceptible to corrosion from chloride solutions (notably saline
environments with high amounts of sodium chloride). Chloride ions can create
localized areas of corrosion, or what is also known as "pitting," which can
spread beneath protective chromium barriers to compromise internal structures.
Solutions with as little as 25 ppm of sodium chloride can begin to have a
corrosive effect.

316 grade is the second-most common form of stainless steel. It has almost the
same physical and mechanical properties as 304 stainless steel and contains a
similar material make-up. The difference is that 316 stainless steel
incorporates about 2 to 3 percent molybdenum, which increases corrosion
resistance - particularly against chlorides and other industrial solvents. 316
stainless steel is commonly used in many industrial applications involving
processing chemicals, as well as high-saline environments such as marine,
coastal regions and outdoor areas where de-icing salts are common. Due to its
non-reactive qualities, 316 stainless steel is also used in the manufacture of
medical industry, surgical instruments, food industry, & pharmaceutical
equipment.

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