Definition
API 5DP — API 5DP is the American Petroleum Institute specification for the manufacture of steel drill pipe, defining dimensions, mechanical properties, grades and inspection requirements for new drill pipe tube and tool joints.
Also known as: API 5DP, API Spec 5DP, ISO 11961
What API 5DP is
API Specification 5DP (aligned with ISO 11961) is the manufacturing standard for new steel drill pipe. It specifies the requirements for the pipe tube and the welded tool joints, including dimensions, tolerances, mechanical properties, chemical composition limits, upset geometry, and the inspection and testing that manufacturers must perform before a joint is delivered.
API 5DP defines the standard drill-pipe grades — E75, X95, G105 and S135 — which set the minimum yield strength of the tube. It also governs the friction weld between tube and tool joint and the marking and traceability of finished pipe.
What it specifies
- Grades and mechanical properties — minimum yield for E75, X95, G105 and S135.
- Dimensions and tolerances — OD, wall, upsets and tool-joint geometry.
- Inspection and testing — nondestructive examination and hydrostatic or dimensional checks at manufacture.
Because it fixes the as-manufactured properties, API 5DP is the baseline against which used-pipe inspection standards such as API RP 7G-2 and DS-1 measure remaining condition.
Why it matters for rentals
Knowing the manufacturing grade and specification of rental drill pipe tells you its original strength and geometry before wear. See our drill pipe and quality program, or contact us for mill and inspection certificates.