STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

~~ ~ ~ ~ ~
736 Drilling and Well Completions
Drill pipe is classified according to:
type of ends upset
sizes (outside diameter)
wall thickness (nominal weight)
steel grade
length range.
Standardized pipe upsets are:
Classification of Drill Pipe
internal upset (IU)
external upset (EU)
internal and external upset (IEU).
Geometrical data of upset drill pipe for weld-on tool joints are specified in
Table 4-77 (steel grades D and E) and Table 4-78 (steel grades X, G and S).
API standardized new drill pipe sizes and unit weights are given in Table 4-79.
Drill pipe is manufactured in the following random length ranges:
Range 1-18 to 22 ft
Range 2-27 to 30 ft
Range 3-38 to 45 ft
The drill pipe most commonly used is Range 2 pipe.
To meet specific downhole requirements, seamless drill pipe is available in
five steel grades, namely D, E, X, G and S*. (Grades X, G and S are considered
to be high-strength pipe grades.) The mechanical properties of these steel grades
are as follows:
API Steel Grade
Property D E X(95) 105(G) 135(S)
Minimum yield strength, psi 55,000 75,000 95,000 105,000 135,000
Maximum yield strength, psi 85,000 105,000 125,000 135,000 165,000
Minimum tensile strenqth, psi 95,000 100,000 105,000 115,000 145,000
For practical engineering calculations, the minimum yield strength is usually
used; however, for some calculations, the average yield strength is used.
Minimum Performance Properties of Drill Pipe
The torsion, tension, collapse and internal pressure resistance for new,
premium class 2 and class 3 drill pipe are specified in Tables 4-80, 4-81, 4-82
and 4-83, respectively.
Calculations for the minimum performance properties of drill pipe are based
on formulas given in Appendix A of API RP 7G. It must be remembered that
numbers in Tables 4-80-4-83 have been obtained for the uniaxial state of stress,
e.g., torsion only or tension only, etc. The tensile stress resistance is decreased
when the drill string is subjected to both axial tension and torque; a collapse
*The above data are obtained from the IADC Drilling Manual, Section B, p. 1, revised January 1975.