Corrosion is one of the leading factors in failing "down hole" components which results in down time, clean up and headaches that ultimatly affect your bottom line. Our goal is to manufacture parts out of materials that last longer in highly corrosive oil field environments. Below is a summary of the materials that are best suited for longevity in corrosive environments.
Brass is an alloy of copper and zinc, and the proportions of zinc and copper can be varied to create a range of brass alloys. We typically use a brass alloy called C360 with a half hard temper. C360 is the most common brass on the market, and is excellent for high speed machine work. It also provides excellent corrosion resistance.
There are certain applications where we will use Naval brass (C464), which substitutes a small amount of tin for a small amount of zinc, giving it an incredibly high corrosion resistance to salt water. The addition of tin also gives the alloy a resistance to wear, fatigue, galling, and stress corrosion cracking.
Brass is typically used for applications where low friction is required such as gears, bearings, and valves. The low friction characteristic of brass makes it our select mateiral for down hole parts. When gasses and explosive fuilds are present, brass is a good option as it will not produce any sparks when interacting with other parts.
316 Stainless Steel:
Unprotected carbon steel easily rusts when exposed to air and moisture. This iron oxide film or "the rust" is active and accelerates corrosion by forming more iron oxide that tends to flake and fall away. Stainless steels contain sufficient chromium to form a passive film of chromium oxide, which prevents further surface corrosion and blocks corrosion from spreading into the metal's internal structure. That being said, not all grades of stainless steel are created equal. 304 stainless steel also known as (18/8 SST) is the most generic and general purpose stainless currently on the market, and most stainless oilfield products are manufactured out of 304 stainless steel. However, we have found that 316 stainless steel is much more suited for highly corrosive environments such as the oilfield. 316 stainless steel has more nickel and molybdenum than 304 stainless steel, which significantly adds to the corrosion resistance of the material. 316 stainless steel is widely used when the material will be exposed to chemical corrodents or marine atmospheres.
316 Stainless Steel References: