Drilling for oil, gas, water, and other natural resources requires a wide range of basic tools and equipment to effectively complete projects. Drill pipe is one of the absolutely necessary tools for any drilling project. Below we'll take a look at drill pipes and break down their classifications, uses, and sizes.

　　What is a drill pipe?

　　Drill pipe is a seamless steel tube that makes up about 95% of the length of the drill string. For clarity, drill strings are used to actually drill into the ground to extract resources. The drill pipe is hollow, allowing the drilling fluid to flow freely throughout the drill pipe and the pumping process completes smoothly.

　　Drill pipe is manufactured to transmit drilling torque over the entire length of the pipe—usually miles. They are also used to resist pressure changes and need to be able to carry the full weight of deeper drilling components. Drill pipe is manufactured by welding together threaded tool joints, box tool joints, and pin tool joints. These subs are used at the top of the drill string to pump fluid and transmit torque to the drill bit.

　　How to measure drill pipe size?

　　The individual joints of the drill pipe are called "singles". "Singles" are then further identified by their length. Specifically, lengths are identified using a three-part API length range, so lengths will be classified as one, two, or three. The most common drill pipe length is range two. This is important because you need to accurately consider the length of the drill string (including drill pipe) when determining the depth of the hole.

　　Drill rods are manufactured in a variety of sizes and materials, which means you have a perfect drill rod for your project. Similar to API length ranges, API categories are also grouped by drill pipe size and material. API grades measure yield strength, tensile strength, drill pipe body, and tool joints.

　　API ratings are given based on inspections that are especially important after the drill pipe is in use. Ultrasonic testing and various other tools are used to provide these measurement ranges.