API 5DP Drill Pipe Specifications

Description

Goldenman supplies API-certified drill pipe in nominal sizes from 2-3/8 to 6-5/8 inches, with E75, X95, G105 and S135 steel grades and multiple EU, IEU, NC and FH configurations.

This page provides dimensional and configuration data for drill pipe bodies and weld-on tool joints, including:

Nominal pipe size and weight
Pipe-body outside diameter
Wall thickness
Steel grade
Upset type
Rotary-shouldered connection
Tool joint outside diameter
Pin inside diameter
Bevel diameter
Pin and box tong-space length
Upset-neck outside diameter
Tool-joint-to-pipe-body torsion ratio

Final dimensions must be confirmed in the approved product datasheet because tool joint geometry can vary according to pipe size, nominal weight, grade and connection.

Product Highlights

Manufactured to the applicable API Spec 5DP requirements
API-certified drill pipe products
Nominal sizes from 2-3/8 to 6-5/8 inches
E75, X95, G105 and S135 grades
EU and IEU upset configurations
NC26, NC31, NC38, NC40, NC46 and NC50 connections
5-1/2 FH and 6-5/8 FH options
Grade-matched weld-on tool joints
Tool joint dimensional and torsion-ratio selection
Optional hardbanding and internal coating
Material traceability and inspection documentation
Replacement drill pipe dimensional matching

API 5DP Drill Pipe Specification Range

Parameter	Available Range
Applicable standard	API Spec 5DP, applicable current edition
Product type	Drill pipe body with weld-on tool joints
Nominal pipe size	2-3/8–6-5/8 in
Nominal weight	6.65–27.7 lb/ft
Pipe body OD	60.32–168.30 mm
Wall thickness	7.11–12.70 mm
Steel grades	E75, X95, G105, S135
Upset types	EU and IEU, according to configuration
Connection range	NC26–NC50, 5-1/2 FH, 6-5/8 FH
Tool joint OD	85.70–215.90 mm
Pin inside diameter	41.28–127.00 mm
Bevel diameter	82.95–195.70 mm
Pin tong-space length	177.80–203.20 mm
Box tong-space length	203.20–279.40 mm
Upset-neck OD	65.09–176.21 mm
Listed torsion ratio	0.79–1.53
Optional treatments	Hardbanding, internal coating and custom marking
Certification	API certificate

Drill Pipe Size, Weight and Connection Matrix

Nominal Size	Nominal Weight	Pipe OD	Wall Thickness	Upset	Available Grades	Connection Options
2-3/8 in	6.65 lb/ft	60.32 mm	7.11 mm	EU	E75, X95, G105	NC26
2-7/8 in	10.4 lb/ft	73.02 mm	9.19 mm	EU	E75, X95, G105, S135	NC31
3-1/2 in	13.3 lb/ft	88.90 mm	9.35 mm	EU	E75, X95, G105, S135	NC38
3-1/2 in	15.5 lb/ft	88.90 mm	11.40 mm	EU	E75, X95, G105, S135	NC38 / NC40
4 in	14 lb/ft	101.60 mm	8.38 mm	According to configuration	E75, X95, G105, S135	NC40 / NC46
4-1/2 in	16.6 lb/ft	114.30 mm	8.56 mm	IEU	E75, X95, G105, S135	NC46
4-1/2 in	20 lb/ft	114.30 mm	10.92 mm	IEU	E75, X95, G105, S135	NC46
4-1/2 in	16.6 lb/ft	114.30 mm	8.56 mm	EU	E75, X95, G105, S135	NC50
4-1/2 in	20 lb/ft	114.30 mm	10.92 mm	EU	E75, X95, G105, S135	NC50
5 in	19.5 lb/ft	127.00 mm	9.19 mm	IEU	E75, X95, G105, S135	NC50 / 5-1/2 FH
5 in	25.6 lb/ft	127.00 mm	12.70 mm	IEU	E75, X95, G105, S135*	NC50 / 5-1/2 FH
5-1/2 in	21.9 lb/ft	139.70 mm	9.17 mm	According to configuration	E75, X95, G105, S135	5-1/2 FH
5-1/2 in	24.7 lb/ft	139.70 mm	10.54 mm	According to configuration	E75, X95, G105, S135	5-1/2 FH
6-5/8 in	25.2 lb/ft	168.30 mm	8.38 mm	According to configuration	E75, X95, G105, S135	6-5/8 FH
6-5/8 in	27.7 lb/ft	168.30 mm	9.19 mm	According to configuration	E75, X95, G105, S135	6-5/8 FH

*The final S135 tool joint dimensions for the 5 in × 25.6 lb/ft NC50 configuration must be confirmed in the approved manufacturing datasheet.

Complete Tool Joint Dimensional Data

In the following table, grade-specific values are listed in the order shown in the “Grades” column.

TJ OD means tool joint pin and box outside diameter.
Pin ID means the inside diameter through the pin connection.
Pin/Box Tong means the available tong-space length.

Pipe Size and Weight	Connection	Grades	TJ OD by Grade, mm	Pin ID by Grade, mm	Bevel Diameter, mm	Pin/Box Tong, mm	Upset-Neck OD, mm	Torsion Ratio by Grade
2-3/8 × 6.65	NC26	E/X/G	85.70/85.70/85.70	45.45/45.45/45.45	82.95	177.8/203.2	65.09	1.10/0.87/0.79
2-7/8 × 10.4	NC31	E/X/G/S	104.80/104.80/111.10/111.10	53.98/50.80/50.80/41.28	100.41	177.8/228.6	80.96	1.03/0.90/0.82/0.82
3-1/2 × 13.3	NC38	E/X/G/S	120.70/127.00/127.00/127.00	68.26/65.09/61.91/53.98	116.28	203.2/266.7	98.43	0.98/0.87/0.86/0.80
3-1/2 × 15.5	NC38	E/X/G	127.00/127.00/127.00	65.09/61.91/53.98	116.28	203.2/266.7	98.43	0.97/0.83/0.90
3-1/2 × 15.5	NC40	S	139.70	57.15	127.40	177.8/254.0	98.43	0.87
4 × 14	NC40	E/X/G/S	133.40/133.40/139.70/139.70	71.44/68.26/61.91/50.80	127.40	177.8/254.0	106.36	1.01/0.86/0.93/0.87
4 × 14	NC46	E/X/G/S	152.40/152.40/152.40/152.40	82.55/82.55/82.55/76.20	145.26	177.8/254.0	114.30	1.43/1.13/1.02/0.94
4-1/2 × 16.6 IEU	NC46	E/X/G/S	158.80/158.80/158.80/158.80	82.55/72.60/76.20/69.85	145.26	177.8/254.0	119.06	1.09/1.01/0.91/0.81
4-1/2 × 20 IEU	NC46	E/X/G/S	158.75/158.75/158.75/158.75	76.20/69.85/63.50/57.15	145.30	177.8/254.0	119.07	1.07/0.96/0.96/0.81
4-1/2 × 16.6 EU	NC50	E/X/G/S	168.28/168.28/168.28/168.28	95.25/95.25/95.25/88.90	154.00	177.8/254.0	127.00	1.23/0.97/0.88/0.81
4-1/2 × 20 EU	NC50	E/X/G/S	168.28/168.28/168.28/168.28	92.08/88.90/88.90/76.20	154.00	177.8/254.0	127.00	1.07/0.96/0.96/0.81
5 × 19.5	NC50	E/X/G/S	168.28/168.28/168.28/168.28	95.25/88.90/82.50/69.85	154.00	177.8/254.0	130.18	1.23/0.97/0.88/0.81
5 × 25.6	NC50	E/X/G	168.28/168.28/168.28	88.90/76.20/69.85	154.00	177.8/254.0	130.18	1.02/0.96/0.86
5 × 19.5	5-1/2 FH	E/X/G/S	177.80/177.80/177.80/184.15	95.25/95.25/95.25/88.90	170.70	203.2/254.0	130.18	1.53/1.21/1.09/0.98
5 × 25.6	5-1/2 FH	E/X/G/S	177.80/177.80/184.15/184.15	88.90/88.90/88.90/82.55	170.70	203.2/254.0	130.18	1.21/0.95/0.99/0.83
5-1/2 × 21.9	5-1/2 FH	E/X/G/S	177.80/177.80/184.15/190.50	101.60/95.25/88.90/76.20	170.70/170.70/170.70/180.20	203.2/254.0	144.46	1.11/0.98/1.02/0.96
5-1/2 × 24.7	5-1/2 FH	E/X/G/S	177.80/184.15/184.15/190.50	101.60/88.90/88.90/76.20	170.70/170.70/170.70/180.20	203.2/254.0	144.46	0.99/1.01/0.92/0.86
6-5/8 × 25.2	6-5/8 FH	E/X/G/S	203.20/203.20/209.55/215.90	127.00/127.00/120.65/107.95	195.70	203.2/279.4	176.21	1.04/0.82/0.87/0.86
6-5/8 × 27.7	6-5/8 FH	E/X/G/S	203.20/209.55/209.55/215.90	127.00/120.65/120.65/107.95	195.70	203.2/279.4	176.21	0.96/0.89/0.81/0.80

The dimensional data above should be used for preliminary selection and comparison. The final manufacturing dimensions, tolerances and connection geometry are governed by the approved datasheet, applicable API requirements and purchase order.

Drill Pipe Grade Identification

Grade	Common Designation	General Classification
E	E75	Standard-strength drill pipe grade
X	X95	High-strength drill pipe grade
G	G105	High-strength drill pipe grade
S	S135	High-strength drill pipe grade
SS	SS75, SS95 or SS105	Sour-service grade when specifically ordered

S135 should not be described as sour-service drill pipe merely because it is a high-strength grade. Sour-service requirements must be stated separately and supported by the applicable material grade and documentation.

EU and IEU Upset Types

EU — External Upset

An EU drill pipe body has additional material concentrated mainly on the outside of the upset area.

The configuration can affect:

Weld-end outside diameter
Transition geometry
Tool joint dimensions
External clearance
Connection compatibility

IEU — Internal-External Upset

An IEU configuration increases the section in both the internal and external directions.

It may provide a different balance between weld-area strength, internal flow area and tool joint geometry.

EU and IEU drill pipe with the same nominal OD, weight and connection should not be considered interchangeable without comparing the complete dimensional specification.

Understanding Rotary-Shouldered Connections

The connection designation defines the thread form and general connection family, but it does not define the complete drill pipe assembly.

For example, two products described as “5-inch NC50 S135 drill pipe” can have different:

Tool joint outside diameter
Pin inside diameter
Bevel diameter
Pin and box tong-space lengths
Upset-neck diameter
Torsion ratio
Hardbanding configuration
Overall pipe length

Replacement drill pipe should therefore be matched using the full dimensional record rather than only the nominal pipe size and thread designation.

Understanding the Torsion Ratio

The listed torsion ratio compares the torsional capacity of the tool joint with the torsional capacity of the drill pipe body.

Ratio Below 1.0

A value below 1.0 indicates that the tool joint may reach its calculated torsional limit before the pipe body.

Ratio Near 1.0

A value close to 1.0 indicates a more balanced relationship between the tool joint and pipe body.

Ratio Above 1.0

A value above 1.0 indicates that the pipe body may become the limiting torsional component before the tool joint.

The torsion ratio is an important comparison parameter, but it is not by itself the permissible field operating torque. Actual torque limits must also consider connection condition, make-up torque, wear, remaining wall thickness and inspection category.

Optional Drill Pipe Configurations

Hardbanding

Hardbanding can be applied to the tool joint wear area according to the approved customer specification.

The order should define:

Hardbanding material
Casing-friendly requirement
Application position
Number of bands
Width and thickness
End-user approval requirement

Internal Coating

Internal coating may be selected to support corrosion control or reduce internal hydraulic friction under suitable operating conditions.

The coating system should be matched to:

Drilling-fluid chemistry
Temperature
Solids concentration
Inspection method
Repair procedure
Expected service environment

Custom Marking and Traceability

Product marking can include:

Manufacturer identification
API marking
Nominal size and weight
Steel grade
Connection
Heat number
Serial or traceability number
Customer identification
Hardbanding or coating code

Manufacturing and Quality Control

Goldenman drill pipe manufacturing and inspection controls can include:

Raw-material certificate review
Heat-number traceability
Chemical-composition verification
Mechanical-property testing
Upset dimensional inspection
Pipe-body outside-diameter inspection
Wall-thickness verification
Tool joint dimensional inspection
Weld alignment and weld-zone inspection
Heat-treatment verification
Hardness testing
Nondestructive examination
Internal drift inspection
Straightness inspection
Thread gauging
Shoulder and sealing-face inspection
Hardbanding inspection
Internal coating inspection
Product marking verification
Final documentation review

The final inspection level and document package are confirmed according to the API-certified product scope and purchase specification.

Available Documentation

The order documentation package can include:

API certificate
Certificate of Conformity
Approved product datasheet
Material test certificates
Chemical-composition report
Mechanical-property report
Heat-treatment records
Nondestructive examination reports
Wall-thickness inspection record
Dimensional inspection report
Weld-zone inspection report
Hardness report
Thread-gauging report
Drift inspection record
Hardbanding report
Internal coating report
Packing list
Product traceability records
Third-party inspection report when ordered

Frequently Asked Questions

What is the difference between a drill pipe body, a tool joint and a complete drill pipe?

The drill pipe body is the tubular section that carries tension, torque and drilling fluid. Tool joints are the threaded pin and box components welded to the pipe-body ends.

A complete drill pipe consists of a drill pipe body with weld-on tool joints. The API certificate scope should be checked to determine whether it applies to the body, tool joint, complete drill pipe or a combination of these products.

Why can the same nominal drill pipe size have different tool joint outside diameters?

Tool joint dimensions vary according to nominal weight, steel grade, connection and required torsional relationship.

A higher-strength pipe body may require a different tool joint OD or pin ID to achieve the required connection capacity. Hydraulic clearance and external wear allowance can also influence the selected geometry.

Is an NC50 connection enough to confirm drill pipe interchangeability?

No. NC50 identifies the connection family, but not the complete tool joint dimensions.

Tool joint OD, pin ID, bevel diameter, tong-space length, upset-neck diameter, hardbanding and overall drill pipe length must also be compared.

Why does the pin inside diameter become smaller on some higher-grade configurations?

A smaller pin ID can increase the metal cross-sectional area of the tool joint and improve its torsional capacity.

However, reducing the pin ID also reduces internal flow area and may increase drilling-fluid pressure loss. Tool joint strength and hydraulic performance must therefore be balanced.

What does a torsion ratio below 1.0 mean?

It means the calculated torsional capacity of the tool joint is lower than that of the pipe body for that configuration.

The tool joint may therefore become the limiting part of the assembly. It does not automatically mean the drill pipe is unsuitable, but the allowable operating torque must respect the weaker component.

Can S135 drill pipe be ordered for H₂S service?

S135 is a high-strength grade and is not automatically a sour-service grade.

For H₂S exposure, provide the actual service conditions and specify the required sour-service grade, material restrictions, hardness limits and inspection documentation.

What dimensions are required to match replacement drill pipe?

Provide:

Nominal size
Nominal weight
Steel grade
Upset type
Connection
Tool joint OD
Pin ID
Bevel diameter
Pin tong-space length
Box tong-space length
Upset-neck OD
Overall length
Hardbanding and coating details

Existing markings, photographs and inspection records should also be supplied.

How is drill pipe wall thickness verified?

Wall thickness is inspected according to a documented procedure applicable to the ordered API specification and inspection scope.

The report should identify the product, heat or traceability number, inspection method, acceptance criteria and inspection result.

Should buyers select drill pipe using torsion ratio alone?

No. Torsion ratio is only one selection parameter.

The complete evaluation should include tensile capacity, expected drilling torque, connection make-up torque, fatigue loading, dogleg severity, hydraulic requirements, external clearance, wear condition and inspection category.

Information Required for Quotation

Please provide:

Nominal drill pipe size
Nominal weight
Steel grade
Upset type
Connection
Tool joint OD
Pin ID
Bevel diameter
Pin and box tong-space lengths
Required pipe length
Quantity
Hardbanding requirement
Internal coating requirement
Sour-service requirement
API certificate requirement
Inspection and NDE requirements
Third-party inspection requirement
Product marking requirement
Destination country
Delivery schedule

For replacement drill pipe, please also provide existing pipe markings, photographs, dimensional records and the latest inspection report.

Request API 5DP Drill Pipe Specifications and Pricing

Goldenman supplies API-certified drill pipe from 2-3/8 to 6-5/8 inches with E75, X95, G105 and S135 grade options.

For an accurate quotation, send your required size, nominal weight, grade, upset type, connection, tool joint dimensions, quantity and inspection requirements to:

Email: info@goldenman.com

Goldenman will prepare the applicable dimensional datasheet, certification package and commercial quotation for your drill pipe requirement.