Drillpipe is seamless steel pipe made up in the drill string and it is the major component of the entire drillstring. Typically, 90% – 95% of the total length is drill pipe. Thread connection of drill pipe is called “Tool Joint”. One end of drill pipe has a female end which is named as “Box” (see Figure 1).

Figure 1 - Box End of Tool Joint

Another end of drill pipe is a male end known as “Pin” (see Figure 2).

 

Figure 2 - Pin End of Tool Joint

Component of Tool Joints – Pin (Figure 3)

 

 Figure 3 - Pin End Component

Component of Tool Joints – Box (Figure 4)

Figure 4 - Box End Component

Figure 5 shows when the drill pipes are made up together.

Figure 5 - Drillpipe Make Up

 Each joint of drill pipe is sometimes called “Single” and the length of each single is classified based on three API length range in the table below (see Table 1).

 

Table 1 - API Range of DrillPipe

The most common drill pipe length is commonly in “Range 2 (R2)”. Each joint of drill pipe does not have the same length therefore all drill pipes must be measured to get an exact length. Drilling depth is measured by length of drill string (drill pipe, drill collar, BHA) hence the right measurement is the key of the right depth.

The drill pipes are manufactured in various sizes, material, etc. In order to standard pipe grade, API classifies drill pipe into several classes based on the table below (Table 2).

 Table 2 - API Drill Pipe Grade

In the industry, there are several drill pipes manufactured from several companies. Therefore, in order to get the detailed specification of particular pipe, it is recommended that you need to find data from the manufacture spec sheet.