Definition
Tensile Strength — Tensile strength is the maximum pulling stress a steel can withstand before it fractures, setting the ultimate limit on how much a drill pipe or connection can be stretched before failure — always higher than the yield strength.
Also known as: tensile strength, ultimate tensile strength, UTS
What tensile strength is
Tensile strength, or ultimate tensile strength (UTS), is the greatest pulling stress a material can bear before it breaks. It sits above the yield strength: yield is where permanent deformation begins, while tensile strength is where the metal ultimately parts. For drill pipe both values are specified per grade, and both matter for string design.
The pipe body tensile load capacity is the tensile strength (or, more commonly for design, the yield strength) multiplied by the cross-sectional area of the tube wall. Exceeding it — for example when a stuck string is over-pulled — risks parting the pipe.
Why it matters
- Overpull limits — the difference between working load and the tensile capacity is the margin of overpull available when freeing stuck pipe.
- Weakest link — tool joints, upsets and the tube each have their own tensile ratings; the lowest governs.
- Combined loading — tension acts together with torque and pressure, reducing the safe pull.
Renting with confidence
Knowing the tensile and yield ratings of your string is essential before any hard pull. We rent drill pipe with documented mechanical properties and inspection class — contact us for the ratings on the sizes and grades you need.