Drill steel pipe Basic concept
Buying drill pipe involves more than selecting an outside diameter and steel grade. Two quotations that both describe “5-inch S135 drill pipe” may differ in nominal weight, wall thickness, upset type, tool joint dimensions, connection, hardbanding, internal coating, inspection scope and finished joint weight.
This guide is written for drilling contractors, oilfield service companies, equipment rental fleets and procurement teams preparing an API 5DP drill pipe enquiry. It explains which technical and commercial details should be included in the RFQ, how to compare suppliers and which omissions can lead to incompatible drill pipe or unexpected costs.
If your specification is already complete, send the RFQ directly to ELITE for a technical and commercial quotation.
Request API Drill Pipe Quotation
Email: info@apidrillpipe.com
WhatsApp: +8618615995257
ELITE supplies API 5DP drill pipe in sizes ranging from 2-3/8″ to 6-5/8″, available in E75, X95, G105 and S135 grades.
For demanding drilling environments, we also offer high-torque double-shoulder connections and sour-service drill pipe suitable for H2S applications.
Information Required in a Drill Pipe RFQ
A request for “drill pipe” or “5-inch S135 drill pipe” is not sufficient for a firm technical quotation. The supplier still has to determine the nominal weight, wall thickness, length range, upset type, tool joint dimensions, connection and optional processing.
A complete RFQ should state:
Pipe body outside diameter
Nominal weight
Wall thickness, when specified
Steel grade
Range 2 or Range 3
Tool joint connection
Tool joint outside diameter
Tool joint inside diameter
Pin and box lengths, when controlled by the drilling program
Product specification level
Hardbanding system
Sour-service requirements
Quantity
Inspection requirements
Third-party inspection
Required documentation
Delivery destination
Required delivery date
If the complete specification is unavailable, send the previous purchase order, existing drill pipe marking, data sheet or clear photographs of the pin and box connections. ELITE can review the available information before preparing the offer.
Request Drill Pipe Price and Delivery Time
Email: info@apidrillpipe.com
WhatsApp：+86 18615995257
ELITE drill pipe manufacturer Main feature
Drill pipe is a seamless steel tube fitting with tool joints at both ends. It is designing to transmit torque, support drill string loads and circulate drilling fluid during drilling operations. Which is using to connect the surface equipment of the drill rig to the drilling and grinding equipment. Or bottom hole device located at the bottom of the drill. Drill pipe transfers drilling fluid from the surface mud system to the drill bit while transmitting torque and axial loads to the bottom hole assembly (BHA).
During drilling operations, drill pipe is subjecting to high internal pressure, external pressure, tension, compression, bending and cyclic fatigue. Therefore, the pipe body and tool joints must provide reliable mechanical performance and fatigue resistance.
With proper inspection and maintenance, drill pipes can be reusing multiple times throughout its service life.
The clean pipe and raw steel pipe are made into drill pipes after several processing steps. First of all, through the processing of the steel pipe thickening process, the surface of the light pipe is curving inward. And the wall of the steel pipe is thickening. Next, the thread is machining and plating with copper to increase strength. A non-destructive quality control test is then carriing out, following by the welding of the pipe body joint. The tube is then subjecting to welding heat treatment and welding final treatment to eliminate welding residual pressure. Before the finished pipes is painted and packaging. The finished steel pipe is subjecting to a number of other tests, including hardness testing, pressure testing and non-destructive testing.
API Spec 5DP Steel Grades & Mechanical Properties
Selecting the correct steel grade depends on well depth, expected tensile load, and downhole H2S corrosion risks:
| API Steel Grade | Min. Yield Strength (PSI / MPa) | Tensile Strength Min. (PSI / MPa) | Elastic Modulus | Recommended Well Application |
| E-75 | 75,000 PSI (517 MPa) | 100,000 PSI (689 MPa) | $210\text{ GPa}$ | Shallow wells, light workover, and low-stress drilling. |
| X-95 | 95,000 PSI (655 MPa) | 105,000 PSI (724 MPa) | $210\text{ GPa}$ | Medium-depth vertical oil and gas wells. |
| G-105 | 105,000 PSI (724 MPa) | 115,000 PSI (793 MPa) | $210\text{ GPa}$ | Deep vertical, horizontal, and directional drilling. |
| S-135 | 135,000 PSI (931 MPa) | 145,000 PSI (1000 MPa) | $210\text{ GPa}$ | Ultra-deep wells, extended-reach drilling (ERD), and high-torque applications. |
Dimensional Specifications & Tool Joint Connections
Below are standard API 5DP drill pipe sizes, pipe wall thicknesses, and corresponding tool joint connections:
| Pipe Outer Diameter (Inches) | Nominal Weight (lb/ft) | Wall Thickness (Inches) | API Length Range | Standard Tool Joint Connection | Tool Joint OD x ID (Inches) |
| 2 3/8″ | 6.65 lb/ft | 0.280″ | Range 2 / Range 3 | NC26 (2 3/8″ IF) | 3 3/8″ x 1 3/4″ |
| 2 7/8″ | 10.40 lb/ft | 0.362″ | Range 2 / Range 3 | NC31 (2 7/8″ IF) | 4 1/8″ x 2 1/8″ |
| 3 1/2″ | 13.30 lb/ft | 0.368″ | Range 2 / Range 3 | NC38 (3 1/2″ IF) | 4 3/4″ x 2 11/16″ |
| 4″ | 14.00 lb/ft | 0.330″ | Range 2 / Range 3 | NC46 (4″ IF) | 6″ x 3 1/4″ |
| 4 1/2″ | 16.60 lb/ft | 0.337″ | Range 2 (27–30 ft) | NC50 (4 1/2″ IF) | 6 3/8″ x 3 1/2″ |
| 5″ (Most Common) | 19.50 lb/ft | 0.362″ | Range 2 (27–30 ft) | NC50 (4 1/2″ IF) | 6 5/8″ x 3 1/2″ |
| 5 1/2″ | 21.90 lb/ft | 0.361″ | Range 2 / Range 3 | 5 1/2″ FH | 7″ x 4″ |
| 6 5/8″ | 25.20 lb/ft | 0.330″ | Range 2 / Range 3 | 6 5/8″ FH | 8 1/2″ x 4 1/4″ |
ELITE Drill Pipe Manufacturing Process & Quality Assurance
As an API 5DP certified manufacturer, our drill pipes undergo a rigorous, fully automated manufacturing process:
Seamless Tube Inspection: Raw alloy steel pipes undergo 100% full-length ultrasonic testing (UT) and magnetic particle inspection (MPI).
Induction Heating & End Upsetting: Pipe ends are heated and hydraulically forged to achieve uniform IU, EU, or IEU end profiles.
Precision Inertia Friction Welding: Tool joints are friction-welding to the upset pipe body, creating a forging metallurgical bond equal to or stronger than the parent metal.
Post-Weld Heat Treatment (PWHT): The weld zone undergoes full-body quenching and tempering to relieve internal residual stresses.
Non-Destructive Testing (NDT): 100% inspection of weld lines via ultrasonic and wet magnetic particle testing, followed by hydrostatic pressure testing and dimensional gauging.
| Manufacturing Stage | Purpose |
| Steel Material Verification | Confirm chemical composition and traceability |
| Pipe Body Inspection | Verify dimensions and quality |
| End Upsetting | Prepare tool joint connection area |
| Heat Treatment | Achieve required mechanical properties |
| Tool Joint Manufacturing | Produce connection components |
| Friction Welding | Join pipe body and tool joint |
| Thread Machining | Produce pin and box connections |
| Hardbanding | Improve wear resistance |
| NDT Inspection | Detect internal and surface defects |
| Final Inspection | Confirm dimensions and documentation |
How Procurement Teams Should Compare Drill Pipe Quotations
Do not compare only the total amount.
Product Configuration
Check that every quotation uses the same:Outside diameter,Nominal weight,Grade,Range,Connection,Tool joint OD,Tool joint ID,Upset type,Finished length,Included Processing.
Confirm whether the price includes:Internal coating,Hardbanding,Thread protectors,Drift testing,Special marking,Bundling,Export packing,Inspection Scope.
Contact ELITE engineers for drill pipe quotes and stock information.
Why Drill Pipe Quotations Can Differ Significantly
Large price differences do not always mean one supplier has a much higher margin.
The difference may come from:Different pipe-body weight,Different steel grade,Different tool joint dimensions,Standard versus premium connection,Different internal coating systems,Different hardbanding materials,Different inspection levels,Third-party inspection,Brand or mill source,Different traceability requirements,Delivery time,Packing method,Warranty scope.
When requesting a price, state whether the quotation should include hardbanding, internal coating, thread protectors, inspection, packing and freight. Otherwise, different suppliers may quote different scopes under the same product description.
Supplier Qualification Checklist
Before placing an order, evaluate whether the supplier can provide evidence for the following areas.
Manufacturing Source
Confirm: Pipe-body manufacturer,Tool joint manufacturer,Upsetting location,Heat-treatment location,Friction-welding location,Threading and finishing location.
A trading company may still be a suitable supplier, but the actual manufacturing and quality-control chain should be clear.
Ask how each joint is traced from raw material to finished product.
A useful traceability system should connect:Heat number,Pipe-body batch,Tool joint batch,Welding record,Heat-treatment record,Inspection report,Finished joint identification,Inspection Capability.
Confirm whether the supplier can perform or arrange:Dimensional inspection,Mechanical testing,Non-destructive examination,Weld-zone inspection,Thread gauging,Hardness testing,Coating inspection,Hardbanding inspection,Export Experience.
ELITE Drill Pipe (FAQ)
Q1: What is a drill pipe used for in oil and gas operations?
A: Drill pipe is used to connect surface rig drive systems to the bottom hole assembly (BHA) and drill bit. It transmits mechanical rotation, applies weight to crush rock, and delivers fluid to flush cuttings out of the hole.
Q2: What material is drill pipe made of?
A: Drill pipes are manufacturing from high-strength seamless alloy steel (such as 4137H, 4145H, or modified carbon-manganese steel) that undergoes precise heat treatment (quenching and tempering) to achieve high tensile and impact properties.
Q3: What information is requiring for a drill pipe quotation?
A:At minimum, provide the outside diameter, nominal weight, grade, range, connection, quantity and delivery destination.
For a firm technical quotation, also provide the tool joint dimensions, coating, hardbanding, inspection and documentation requirements.
Q4: Why are two drill pipes quotations different even when the size and grade are the same?
A:The quotations may use different nominal weights, tool joint dimensions, connections, coating systems, hardbanding, inspection scopes, documentation or delivery terms.Request a technical deviation list from each supplier.
Q5: Should we buy G105 or S135 drill pipe?
The decision should follow the drilling program and engineering calculations.
S135 provides higher specified strength, but grade selection must also consider fatigue, connection capacity, corrosion, sour-service conditions and existing drill-string compatibility.
Q6: What documents should we receiving before shipment?
A:The exact package depends on the purchase order, but it commonly includes material certificates, mechanical test reports, NDT reports, dimensional reports, thread inspection, coating or hardbanding reports, traceability records and packing lists.
Q7: Can third-party inspection be arrangind?
A:Yes. The inspection agency, scope, hold points, witness points, cost and reporting format should be confirmingd before production.
Q8: Can you supply sour service drill pipe?
A: Yes. Sour-service drill pipe can be supplied for H2S environments subject to project requirements.
Q9: Can you supply drill pipe for horizontal wells?
A: Yes. Drill pipe can be selected for vertical, directional, horizontal and extended-reach drilling projects.
Need Custom API 5DP Drill Pipes for Your Next Project?
ELITE is a trusted manufacturer supplying certified drill pipes, heavy weight drill pipes (HWDP), and drill collars globally.
API Spec 5DP & ISO 9001 Certified
Available Sizes: 2 3/8″ to 6 5/8″ OD
Options: Hardbanding (Arnco 100XT), Internal Plastic Coating (IPC), Custom Tool Joint Threads
Third-Party Inspection Supported: SGS, Bureau Veritas (BV), Intertek
Get Factory Direct Pricing & Download Full Specification Sheet
Contact our technical sales team today for a free quote within 2 hours:
Email: info@apidrillpipe.com
WhatsApp：+86 18615995257
Fast Inquiry: Submit your required outer diameter (OD), steel grade, and quantity to get an instant quote.
