The term “oil country tubular goods” is used to refer to a specific and specialized type of piping and tubing products used in the petroleum industry. Commonly called OCTG, oil country tubular goods are primarily used to transport oil and gasoline. Although the term is most often used in reference to the casing and tubing used, it can also be used in reference to the line pipe. OCTG also have their own category of connections, or couplings, used to connect sections of tubing or line pipe, each with its own purpose and intended usage.
OCTG casing is piping that is inserted into the drilling well and cemented into place to line the well and serve as a structural retainer. Typically, casing is made from heavy, seamless tubing, which prevents the drilling well from collapsing in on itself while drilling is being done. OCTG casing is usually available in pipe widths varying from a few inches to sometimes up to a few feet, and it comes in a variety of grade levels.
OCTG tubing refers to the pipe used to transport the oil or gas up through the well to the surface. In an effort to prevent leaks throughout the length of the structure, seamless tubing is most often used for this purpose. OCTG tubing is also available in a variety of sizes and quality grades.
