What Is Drill Pipe?

The following are some basic characteristics and uses of drill pipe:
Drill pipe is usually made of high-strength alloy steel or other wear-resistant materials to cope with the high strength and wear in underground environments.
Diameter and Length: Drill pipe diameter and length vary depending on specific drilling needs. The diameter is usually determined based on the hole size to be achieved and the tools used. The length is determined based on the depth of drilling and the depth of the target layer to be reached.
Both ends of the drill pipe are usually designed with special connecting threads to facilitate connection with other drilling tools (such as drill bits, drill pipe connectors, etc.). This helps maintain overall structural strength during drilling.
There are different types of drill pipes, including solid drill pipes, hollow drill pipes and rotary drill pipes, etc. Each type has its specific application scenarios and advantages. In horizontal drilling, drill pipes are usually used to drill horizontally underground to obtain information about underground geological structures and resource distribution.
Drill pipe joint classification
The drill pipe joint is an integral part of the drill pipe. It is divided into male and female joints and is connected to both ends of the drill pipe body. In order to enhance the connection strength of the joint, the wall thickness of the pipe body needs to be increased at the joint part. According to the thickening method, it can be divided into three forms: internal thickening, external thickening, and internal and external thickening. The joints are threaded (threaded) to connect individual drill pipes. The threads of the drill pipe joints are tapered pipe threads with a sealing shoulder. The shoulder surface is tightened to seal, and the thread only serves to connect. Different thickening methods have different thread buckle types of corresponding joints.
Threaded drill pipe joints are divided into four types: internal flat (IF), through hole (FH), regular (REG), and digital (NC).
Button connection conditions
There are three conditions that must be met for a buckle connection:
①The sizes are equal;
②The thread type is the same;
③The male and female buckles match.
Drill pipe joint buckle type
Internal flat type: mainly used for externally thickened drill pipes. Its characteristic is that the inner diameter of the drill pipe is the same, and the drilling fluid flow resistance is small; but the outer diameter is larger and easy to wear. Through-eye type: Mainly used for thickening drill pipe inside and outside. Its characteristic is that the drill pipe has two inner diameters. The drilling fluid flow resistance is greater than the inner flat type, but its outer diameter is smaller than the regular type. Formal type: Mainly used for internally thickened drill pipes, drill bits, and fishing tools. Its characteristic is that the inner diameter of the thickened part of the joint is smaller than the inner diameter of the pipe, and the drilling fluid flow resistance is large. The relative flow resistance is the largest among the three buckle types, but the outer diameter is the smallest and the strength is greater. The above three types of joints all use V-shaped threads, but the buckle type, buckle pitch, taper and size are very different.
Most oil drill pipe joints adopt the form of external thickening or internal and external thickening. The outer diameter of the drill pipe joint is larger than the outer diameter of the pipe. During the drilling process, it constantly contacts and rubs with the well wall or casing, causing wear. In order to avoid joint wear and cause drill breakage To prevent drilling accidents such as rod and tripping, a drill pipe joint anti-wear belt must be installed on the drill pipe female joint.