Oil & Gas Plating

Plating for the Oil and Gas (Petrochemical) Industry

When it comes to the impact on the global economy and importance to human survival, few industries can rival the oil and gas (petrochemical) industry. Nations around the world depend on oil and gas for the energy to heat homes and businesses and the fuel to power automobiles and other modes of transportation. While oil represents only about 2.5 percent of the global GDP, it accounts for approximately one-third of the world's energy supply. Additionally, gas constitutes about 23 percent of the world's commercial energy mix.

According to U.S. Energy Information Administration figures, the United States ranked third in global crude production in 2015, yielding approximately 9.3 million barrels per day. The U.S. also consumed about 19.11 barrels of petroleum products on a daily basis in 2014. Natural gas supplies about 24 percent of our energy, and the volume of natural gas consumption is projected to rise through 2030 and beyond.

The Need for Oil and Gas Plating

While oil and gas are available in abundant supply, they must be extracted from beneath the surface of the earth and ocean floors. This requires the use of various types of equipment such as pumps, drills, separators and shakers, which are made up of many metal parts and components. The combination of harsh environments and the constant pounding caused by drilling and related processes adds a heavy toll on extraction equipment. Consequently, oil and gas equipment manufacturers rely on metal finishing and plating to protect their products and prolong their lifespan.

What Is Plating on Metal?

Plating is a finishing process used to apply a protective coating on the surface of a metal part. The two types of plating on metal are:

• Electroplating: Also known as electrodeposition, electroplating makes use of a specially developed electrolyte plating solution and an electric current to coat the metal part with dissolved ions of another metal such as gold, nickel or copper.
• Electroless plating: Electroless plating also applies a metal coating to a metal part. The key difference is that, unlike electroplating, electroless plating does not require an electric current. Instead, deposition occurs via an autocatalytic chemical reaction. While various metals are used in electroless plating processes, nickel generally provides the best results in most industrial applications.

What Are the Benefits of Plating on Metal?

Electroplating and electroless plating provides a number of important benefits including:

• Wear resistance: The application of a metal coating provides a protective barrier that can increase the wear resistance of the underlying part and reduce the impact of friction.
• Corrosion resistance: Many types of metals will act as a sacrificial coating that resists rust-forming oxidation, which is especially important in offshore oil and gas (petrochemical) industry drilling applications.
• Electrical conductivity: A coating of metals such as gold or copper can increase the ability of electrical components to conduct electricity.
• Heat resistance: Many oil and gas (petrochemical) industry processes involve or create intense heat. A metal coating can serve as an effective heat shield that prevents damage and prolongs part life.
• Increased hardness: Plating on metal can increase the hardness of a part, which helps it withstand the intense pounding that is part of many oil and gas (petrochemical) industry processes.

Let's take a closer look at the various types of oil and gas plating processes.

Gold Plating

Gold is a highly valuable precious metal known for its remarkable aesthetic appeal. However, gold also contains a number of important properties that make it extremely beneficial in metal finishing applications. Gold is an excellent conductor of electricity, making gold plating a preferred choice for coating parts and components such as electrical contacts, switches and connector pins.

Gold-plated parts also exhibit excellent resistance against corrosion, which is important for preventing equipment used in offshore/subsea oil and gas drilling operations from rusting due to prolonged exposure to seawater. Other benefits of gold plating on metal for gas industry and oil extraction applications include increased hardness and solderability, as well as excellent thermal protection in high-temperature environments.

An example of a common gold-plating application for the oil and gas industry is providing a protective coating on the slip rings/ swivels used on Floating Production Storage and Offloading (FPSO) vessels. The gold plating helps to prevent corrosion caused by exposure to saltwater. Gold plating can also be used for a wide range of metals for the manufacturing of oil and gas industry equipment such as stainless steel and aluminum, as well as copper and nickel-silver alloys.

Silver Plating

Silver is another member of the precious metals family that offers significant value beyond its gleaming, lustrous appearance. In addition to being less expensive than gold, silver is known for its excellent electrical conductivity and is also regarded as the best heat conductor of all the metals used for plating applications. Other beneficial silver characteristics include excellent lubricity and good solderability. Silver is classified as a noble metal, which means it can effectively combat the effects of many harmful acids and chemicals.

A common application of silver plating on metal for oil industry and gas industry operations is coating dynamic sealing and bearing surfaces in drill bit parts and components for lubricity. Other components that may be plated with silver include electrical contacts and connectors, shims and gaskets. Additionally, silver plating is extremely effective in anti-galling applications.

When plating with silver, it is imperative to ensure the surface is free of any defects or tensile stress. Thus, proper surface preparation is essential for a successful outcome. Because silver is susceptible to tarnishing, it is often necessary to apply some sort of anti-tarnishing treatment.

Copper Plating

Copper is a reddish-brown metal known for its excellent thermal and electrical conductivity. Copper is also extremely malleable and ductile, making it ideally suited for many types of manufacturing processes. Because copper is not a precious metal and is available in abundant quantities, it is much less expensive than gold or silver. Consequently, many cost-conscious companies choose copper plating as a low-cost alternative for applications requiring enhanced electrical conductivity for parts and components such as printed circuits and connectors. Copper plating also offers good solderability.

The common application for copper oil and gas plating is to prevent galling during make-and-break operations. A copper coating may be applied to parts and components such as premium threaded connections, couplings, tubulars, risers and alloy premium drill pipes for this purpose. Copper is also extremely useful as an undercoating for other plated metals to enhance rust resistance in high-corrosion environments. When used as an undercoat, copper can cover substrate defects such as splinters and holes prior to application of the final deposit. Copper plating is compatible with many types of metals including steel, stainless steel and steel alloys, as well as aluminum and copper alloys.

Zinc Plating

Zinc is a hard, brittle metal with a bluish-white appearance. Zinc oil and gas plating is primarily used to take advantage of zinc's solid corrosion protection properties. Many oil and gas industry products require zinc-coated or zinc-electroplated materials to provide corrosion protection in harsh elements or seawater applications. Examples of products utilizing zinc plating include galvanized fasteners, flanges and pipeline fittings.

Electroplated zinc coatings are typically applied at thicknesses ranging from just a few microns for cheaper materials to 15 microns or more for high-quality fasteners and other more expensive iron and steel parts and components. A zinc coating will slow the onset of corrosion at a rate of 10 to 100 times depending on environmental and atmospheric conditions and other factors. A freshly plated zinc surface is highly reactive when first exposed to the atmosphere. However, a thin protective film will rapidly develop, which significantly reduces the corrosion rate of the zinc-plated substrate.

Nickel Plating

Nickel is a silvery-white, lustrous metal featuring a high melting point, excellent ductility and strong resistance to corrosion and oxidation. Nickel also alloys readily with many other metals, and this versatility enables the use of nickel in a wide range of manufacturing processes. According to the Nickel Institute, approximately 65 percent of nickel used in manufacturing is for the production of stainless steel, while 20 percent is used to manufacture other steel and non-ferrous products. Metal plating accounts for about nine percent of nickel manufacturing practices.

Because of its excellent anti-corrosion properties, nickel is a popular choice for many oil and gas plating applications. A prime example is the selective plating of a nickel solution onto materials used in high-chloride down-hole operations.

Additionally, alloying nickel with copper is sometimes used to repair mechanically damaged surfaces in oil and gas operations. For instance, a plated nickel-copper coating can be applied to repair crown-mounted compensators on oil rigs that incur damage from a lightning strike. This plating technique increases the hardness of the damaged surface and also provides additional protection against surface wear.

Electroless Nickel Plating

Plating with nickel is also achievable without the use of electricity. Electroless nickel plating makes use of an autocatalytic chemical reaction to apply a uniform nickel coating on metal parts and components. With electroless nickel plating, the nickel is combined with phosphorous in the plating bath. The typical phosphorous content ranges are 2-4 percent (low phosphorous), 6-9 percent (medium phosphorous) and 10-12 percent (high phosphorous). The electroless plating process offers greater coating uniformity when plating parts and components featuring complex shapes, while also providing increased control over coating thickness.

According to Coventya, approximately 15 percent of all electroless nickel produced in the world is used for petroleum-based applications. Examples include petroleum exploration operations, refineries and delivery to end-users.

As with nickel electroplating, electroless nickel plating provides excellent protection against corrosion. This makes it a popular choice in oil and gas industry operations where exposure to seawater or corrosive fluids could lead to the premature demise of piping, valves and other delivery components. High-phosphorus nickel coatings tend to provide the best protection against corrosion in saltwater environments. Electroless nickel plating is compatible with a wide range of metals including steel, stainless steel, copper alloys and aluminum.

Passivation

In addition to metal plating, there are a number of other metal finishing processes used for oil and gas industry products. A procedure known as passivation can remove surface contaminants that are byproducts of manufacturing processes such as metal fabrication, welding, heat treating and grinding. Often used as a corrosion prevention process for stainless steel, passivation entails treating the surface with a mild oxidant to remove free iron and other foreign materials. This produces a corrosion-resistant passive film that can withstand environmental elements such as moisture and air that combine to form surface rust. In essence, passivation restores the original engineering characteristics of the metal.

Although stainless steel offers good corrosion resistance on its own, passivation will provide the extra layer of corrosion protection that is essential for preventing the onset of rust in harsh saltwater environments. Some grades of stainless steel are more corrosion-resistant than others and will benefit even more from the passivation process. Passivation requires a thorough cleaning of the surface to enable proper adhesion of the oxidant. The actual passivation bath for stainless steel may consist of either a nitric acid- or citrus acid-based solution in various concentrations and temperature ranges.

Chem Film

Chemical film coating, also known as chromate conversion, is a metal finishing process that offers excellent corrosion protection for products made of aluminum and aluminum alloys. Typical oil and gas industry products manufactured from aluminum include conveyor pipes, riser components, drill pipes and many others. Chem film passivates the aluminum surface, which provides corrosion protection and can also serve as an undercoat for other organic coatings. A key chem film benefit is that it will not alter the dimensions of the part or component in any way. Chem film application processes include spraying, dipping and brushing.

Because of its superior corrosion protection properties, chem film is a popular choice for coating aluminum products in the saltwater environments that are commonplace in the oil and gas industry. An effective chemical film will withstand hundreds of hours of salt spray before the initial appearance of rust during testing. Other capabilities include masking for selective surface coating and repairing anodized surfaces.

Sharretts Plating Company Can Meet All Your Oil and Gas Plating Needs

Sharretts Plating Company has provided innovative metal finishing solutions for more than 90 years. Our wide range of metal finishing services includes advanced techniques for plating on metal for oil and gas industry manufacturers. We offer zinc, gold, silver, nickel and copper plating, as well as electroless nickel plating, chem film, passivation and much more. We can also customize any of our processes to your specific industrial applications.

At SPC, we make quality the primary focus in every oil and gas plating service we offer. We're proud to be an ISO-certified metal finishing company committed to continuous improvement in every phase of our operation. As a customer-focused metal plating company, our goal is to ensure the total satisfaction of every business we serve. Expert consulting services are also available to help you select the best metal finishing solution that meets your company's needs and budget requirements.