About Us
Eastern Steel Manufacturing Co.,Ltd is a leading manufacturer and distributor of seamless steel pipe, welded steel pipe, OCTG products and fittings. We supply first-step processing, semi-finished parts and finished parts to help our clients meet fabrication requirements beyond their capacity or to improve operations by moving forward the pre-production processing.
News
In this column you can find the steel pipe related articles you need, including industry trends, product standards and materials, and some technical guidelines.
Services
Eastern Steel Manufacturing Co.,Ltd not only improve product production and sales services, but also provide additional value-added services. As long as you need, we can complete your specific needs together.
Facility
Eastern Steel Manufacturing Co.,Ltd not only improve product production and sales services, but also provide additional value-added services. As long as you need, we can complete your specific needs together.
Projects
Many years of large-scale project experience in various fields（Oil & Gas, Construction, Power Energy, Marine & Offshore, Water Treatment, Exploration & Drilling Services, Pipeline & Petrochemical etc.）, professional project team is responsible from receiving until the end of the project.
1. What Is API Spec 5DP?
API Spec 5DP is the industry standard for steel drill pipe used in oil and gas drilling.It specifies the requirements for drill pipe dimensions, steel grades, mechanical properties, manufacturing, inspection, and testing.
API Spec 5DP covers the complete finished drill pipe, including the pipe body, tool joints, weld zones, and final inspection requirements. It has become the internationally recognized specification adopted by drilling contractors, EPC companies, and oil and gas operators worldwide.
API Spec 5DP classifies drill pipe into four standard steel grades based on yield strength and mechanical performance. Higher grades are used for deeper wells, higher drilling loads, and more demanding operating conditions.
- E75 – Conventional and shallow drilling
- X95 – Medium-depth drilling
- G105 – Deep well applications
- S135 – Ultra-deep, high-pressure, and high-torque drilling
| Grade | Minimum Yield Strength (psi) | Minimum Tensile Strength (psi) | Minimum Elongation (%) | Minimum Impact Energy (ft-lbs) | Maximum Hardness (HRC) |
|---|---|---|---|---|---|
| E75 | 75,000 | 100,000 | 20 | 40 | ≤30 |
| X95 | 95,000 | 105,000 | 15 | 40 | ≤32 |
| G105 | 105,000 | 115,000 | 13 | 40 | ≤35 |
| S135 | 135,000 | 145,000 | 10 | 40 | ≤38 |
The minimum mechanical property requirements for each grade are shown below.
API Spec 5DP specifies the chemical composition requirements for each steel grade. Carbon, manganese, phosphorus, sulfur, and alloying elements are controlled to achieve the required strength, toughness, and weldability.
The table below summarizes the chemical composition requirements for API 5DP steel grades.
| Grade | Carbon (C, %) | Manganese (Mn, %) | Phosphorus (P, %) | Sulfur (S, %) | Silicon (Si, %) | Chromium (Cr, %) | Nickel (Ni, %) | Molybdenum (Mo, %) | Copper (Cu, %) |
|---|---|---|---|---|---|---|---|---|---|
| E75 | ≤0.35 | 0.60–1.10 | ≤0.020 | ≤0.010 | ≤0.35 | ≤0.15 | ≤0.25 | ≤0.20 | ≤0.20 |
| X95 | ≤0.35 | 0.60–1.10 | ≤0.020 | ≤0.010 | ≤0.35 | 0.75–1.15 | 0.40–0.75 | 0.15–0.25 | ≤0.20 |
| G105 | ≤0.35 | 0.60–1.10 | ≤0.020 | ≤0.010 | ≤0.35 | 0.75–1.15 | 0.40–0.75 | 0.15–0.25 | ≤0.20 |
| S135 | ≤0.35 | 0.60–1.10 | ≤0.020 | ≤0.010 | ≤0.35 | 0.75–1.15 | 0.40–0.75 | 0.15–0.25 | ≤0.20 |
Note: The values shown are the specified chemical composition limits in API Spec 5DP. Actual composition may vary slightly depending on the manufacturing process and steel grade.
API Spec 5DP specifies the standard dimensions for drill pipe, including outside diameter (OD), wall thickness, weight, upset type, and connection type. Standard sizes range from 2 3/8 in. to 6 5/8 in.
The specification also defines standard drill pipe lengths (R1, R2, and R3) and compatible rotary shoulder connections, including NC, IF, FH, and REG.
The following table summarizes the standard API 5DP drill pipe dimensions.
|
Nominal Size |
Weight (lb/ft) |
OD (mm) |
Wall Thickness
(mm)
|
Upset Type |
Standard Connection |
|---|---|---|---|---|---|
| 2 3/8 | 6.65 | 60.32 | 7.11 | EU | NC26 |
| 2 7/8 | 10.40 | 73.02 | 9.19 | EU | NC31 |
| 3 1/2 | 13.30 | 88.90 | 9.35 | EU | NC38 |
| 4 | 14.00 | 101.60 | 8.38 | EU / IU | NC40 / NC46 |
| 4 1/2 | 16.60 | 114.30 | 8.56 | EU / IEU | NC46 / NC50 |
| 5 | 19.50 / 25.60 | 127.00 | 9.19 / 12.70 | IEU | NC50 / 5½ FH |
| 5 1/2 | 21.90 / 24.70 | 139.70 | 9.17 / 10.54 | IEU | 5½ FH |
| 6 5/8 | 25.20 / 27.70 | 168.28 | 8.38 / 9.19 | IEU | 6⅝ FH |
Complete dimensional requirements are available in the official API specification and are summarized in the Drill Pipe Size Chart.
API 5D was the earlier API standard for drill pipe and primarily specified the requirements for the drill pipe body, including dimensions, materials, and basic mechanical properties.
API Specification 5DP replaced API 5D by expanding the scope to cover the complete finished drill pipe. In addition to the pipe body, it specifies requirements for tool joints, weld zones, manufacturing, inspection, testing, marking, and documentation. Today, API Spec 5DP is the current API standard for steel drill pipe used in oil and gas drilling.
The table below summarizes the main differences between the two specifications.
| Feature | API 5D | API Spec 5DP |
|---|---|---|
| Scope | Drill pipe body | Complete finished drill pipe |
| Coverage | Materials and basic dimensions | Dimensions, steel grades, manufacturing, inspection, testing, marking, and documentation |
| Tool Joints | Limited requirements | Included |
| Weld Zone | Not covered | Covered |
| Inspection Requirements | Basic | Comprehensive |
| Current Status | Superseded | Current API standard |
Reference: This comparison is based on the technical requirements defined in API Specification 5DP – Specification for Drill Pipe (latest applicable edition) and the superseded API Specification 5D, published by the American Petroleum Institute (API).
Q1. What steel grades are included in API Spec 5DP?
API Spec 5DP includes four steel grades: E75, X95, G105, and S135. As the grade increases, the drill pipe offers higher strength and is suitable for deeper wells and more demanding drilling conditions.
Q2. What drill pipe sizes does API Spec 5DP cover?
API Spec 5DP covers standard drill pipe sizes from 2 3/8 in. to 6 5/8 in. It also defines standard wall thicknesses, weights, upset types, thread connections, and length ranges (R1, R2, and R3).
Q3. Did API Spec 5DP replace API 5D?
Yes. API Spec 5DP replaced API 5D and is the current API standard for steel drill pipe. It covers the complete finished drill pipe rather than only the pipe body.
Q4. Is API Spec 5DP the current drill pipe standard?
Yes. API Spec 5DP is the current API specification for steel drill pipe used in oil and gas drilling and is widely adopted throughout the industry.
Q5. Does API Spec 5DP cover tool joints?
Yes. In addition to the pipe body, API Spec 5DP includes requirements for tool joints, weld zones, inspection, and testing to ensure the performance of the finished drill pipe.
Q5. Where can I download the API Spec 5DP PDF?
API Specification 5DP is a copyrighted publication of the American Petroleum Institute (API). Official PDF copies are available through authorized API distributors rather than free public downloads.
Q6.Does API Spec 5DP apply to seamless drill pipe?
Yes. API Spec 5DP applies to seamless steel drill pipe used in oil and gas drilling and defines the technical requirements for dimensions, steel grades, manufacturing, inspection, and testing.
E-mail: sales@eastern-steels.com
