API Standard Oil Well Pipe - Specs, Grades & Sizes

Kuaima Steel Co., Ltd.

Verified Custom manufacturer 7yrs

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Technical Specifications of API Standard Oil Well Pipe

Property	Parameter	Description
Product Name	API Standard Oil Well Pipe	Steel pipe designed for oil and gas well drilling and production
Material Grade	API 5CT J55 / K55 / N80 / L80 / P110	Common API casing and tubing grades
Standard Compliance	API 5CT, API 5B, ISO 11960	Meets international oil well pipe standards
Manufacturing Process	Seamless (Hot Rolled)	Seamless steel pipe for high-pressure downhole service
Carbon (C)	≤0.35%	Varies by grade, ensures strength and toughness
Manganese (Mn)	≤1.90%	Improves hardenability and tensile strength
Phosphorus (P)	≤0.030%	Controlled for impact toughness
Sulfur (S)	≤0.030%	Low sulfur for improved weldability and ductility
Tensile Strength	517 - 1000 MPa	Range from J55 (≥517 MPa) to P110 (≥862 MPa)
Yield Strength	379 - 758 MPa	Range from J55 (379-552 MPa) to P110 (758-965 MPa)
Elongation	≥15%	Minimum elongation per API 5CT requirements
OD Range	2-3/8'' - 20'' (60.3 - 508 mm)	Standard casing and tubing outer diameter options
Wall Thickness	3.18 - 16.13 mm	Per API 5CT schedule and weight class
Length	R1 (4.88-7.62m) / R2 (7.62-10.36m) / R3 (10.36-14.63m)	API standard length ranges
Thread Type	STC / LTC / BTC / Premium	Short, long, buttress thread and premium connections
Application	Oil well casing, tubing, drilling operations	Upstream oil and gas exploration and production
Certification	API 5CT Monogram, ISO 9001, EN 10204 3.1	Quality certifications and mill test reports provided
Packaging	Bundled with steel strips, thread protectors, plastic caps	Standard export packaging for pipe protection
MOQ	10 tons	Minimum order quantity

API Standard Oil Well Pipe - Specs, Grades & Sizes

API standard oil well pipe serves as the backbone of modern petroleum extraction, engineered to withstand extreme downhole pressures, corrosive environments, and high-temperature conditions encountered during drilling and production operations. Manufactured in strict compliance with American Petroleum Institute specifications, these tubular products are the preferred choice for oil and gas operators seeking reliable wellbore integrity. Whether you require casing, tubing, or drill pipe, our mill-direct supply ensures consistent quality with full traceability for upstream energy projects worldwide.

What Is API Standard Oil Well Pipe?

API standard oil well pipe refers to seamless or welded steel tubular products manufactured according to API Specification 5CT (casing and tubing) and API Specification 5D (drill pipe). These pipes are purpose-built to line wellbores, convey hydrocarbons from subsurface reservoirs, and provide structural support during drilling operations. Each joint undergoes hydrostatic testing, non-destructive examination, and dimensional verification to guarantee performance under demanding oilfield conditions.

API standard oil well pipe supplier

API Standard Oil Well Pipe Technical Specifications

Our oil well pipe inventory covers the full range of API 5CT grades and configurations commonly deployed across global oilfield operations. Below is a summary of key parameters:

API standard oil well pipe wholesale

Parameter	Specification
Governing Standard	API 5CT (PSL-1 & PSL-2), API 5D
Common Grades	J55, K55, N80, L80, P110, C95, T95
Outside Diameter	2-3/8″ to 20″ (60.3 mm to 508 mm)
Wall Thickness	4.24 mm to 16.13 mm per grade and size
Yield Strength (J55)	379–552 MPa (55,000–80,000 psi)
Yield Strength (P110)	758–965 MPa (110,000–140,000 psi)
Thread Connections	STC, LTC, BTC, premium connections
Length Range	R1 (16–25 ft), R2 (25–34 ft), R3 (34–48 ft)
Surface Treatment	Varnish coating, phosphate coating, or bare

Key Grades of API Oil Well Pipe

J55 and K55 Casing Pipe

J55 and K55 represent entry-level carbon steel grades with minimum yield strengths of 379 MPa and 552 MPa maximum. These grades find extensive application in surface casing and intermediate casing strings where formation pressures remain moderate. Their cost-effective pricing makes them ideal for shallow to mid-depth well construction.

N80 and L80 Tubing and Casing

N80 delivers a minimum yield strength of 552 MPa, suitable for intermediate and production casing in deeper wells. L80, with controlled hardness not exceeding 23 HRC per API 5CT Section 7.8, is commonly employed for sour service environments containing hydrogen sulfide (H₂S) concentrations above 0.05 psi partial pressure, complying with NACE MR0175/ISO 15156 requirements.

P110 High-Strength Casing

P110 grade oil well pipe provides exceptional mechanical strength with a minimum yield of 758 MPa, designed for deep well and high-pressure reservoir applications. This grade is frequently selected for production casing strings operating at depths exceeding 12,000 feet where collapse and burst resistance are critical.

Frequently Asked Questions

What is the minimum order quantity (MOQ)?

Our standard MOQ for API oil well pipe is 20 metric tons per grade and size combination. Smaller trial orders may be accommodated upon request depending on current mill inventory availability.

Do you provide material test certificates?

Yes, every shipment includes EN 10204 Type 3.1 mill test certificates documenting chemical composition, mechanical properties, hydrostatic test results, and NDE records in full compliance with API 5CT requirements.

What is the typical delivery time?

Stock items ship within 7–15 business days. Custom orders involving specific grades, premium connections, or non-standard lengths typically require 30–45 days from order confirmation to ex-works readiness.

Can you supply pipe with premium threaded connections?

Absolutely. Beyond standard STC, LTC, and BTC threads, we offer premium gas-tight connections engineered for enhanced sealing performance in high-pressure, high-temperature, and directional well applications.

Get a Competitive Quote for API Standard Oil Well Pipe

Ready to source reliable API standard oil well pipe for your next drilling project? Contact our oilfield tubular specialists today with your required grades, sizes, quantities, and connection preferences. We deliver factory-competitive pricing backed by full API monogram certification and responsive logistics support to major oil-producing regions worldwide.

API standard oil well pipe China

Ratings & Reviews

5.0

Very satisfied

Based on 8 reviews for verified purchases

Supplier service

5.0

On-time shipment

5.0

Supplier service

5.0

Carlos Silva

Brazil

verified purchases

2025-02-17

Acceptable Quality — Packaging Issue Resolved
Ordered 20 tons of J55 casing 7" OD with STC connections. Pipe quality and API 5CT certificates were fine, but some bundles had damaged wooden cradles on arrival at Santos port, causing minor surface scratches on 4 joints. Supplier agreed to a small credit and improved packaging for our next order. Material itself met specs.

Wei Chen

Singapore

verified purchases

2025-03-11

Reliable L80 Tubing Supply for Southeast Asia Client
Sourced 45 tons of L80 tubing 3-1/2" OD with premium connections for our end client's sour gas well in Myanmar. Pricing was competitive after negotiation on a 2-shipment commitment. NACE compliance documentation was thorough. Delivery took 38 days for the custom premium connection, which was within the quoted window. Would prefer slightly faster lead time on non-stock items, but overall a dependable supplier.

William Taylor

Australia

verified purchases

2025-04-02

Good Value P110 Casing for Cooper Basin Project
Compared quotes from 4 suppliers for 50 tons of P110 casing, 5-1/2" OD with BTC threads. This supplier was about 8% lower than the nearest competitor while maintaining API monogram certification. Material quality was solid — no rejects after our third-party inspection. Only minor point: some thread protectors were slightly loose during transit, but no thread damage found.

Chris Martin

Canada

verified purchases

2025-04-24

Perfect Repeat Order — K55 and N80 Mixed Shipment
Third order in 14 months. This time 25 tons K55 surface casing 9-5/8" and 35 tons N80 intermediate casing 7" OD, both with LTC connections in R2 lengths. Quality has been consistent across all three shipments. Drift testing passed on every joint at our pipe yard inspection. Our procurement team now treats this supplier as our primary source for API 5CT products.

Ahmed Al-Hassan

UAE

verified purchases

2025-05-16

Premium Service on Urgent J55 Surface Casing Order
Needed 30 tons of J55 surface casing, 13-3/8" OD with STC connections urgently for a rig waiting in Abu Dhabi. Sales team confirmed stock availability within 6 hours and arranged shipping in 9 days. Varnish coating and thread protectors were in good condition on arrival. All documentation including hydrostatic test results was emailed before cargo reached port. Responsive and professional throughout.

Hans Mueller

Germany

verified purchases

2025-06-07

Outstanding N80 Casing Delivered Ahead of Schedule
Ordered 60 tons of N80 casing pipe, 7" OD × 8.05 mm wall with LTC threads for an intermediate casing string in our Libya project. Chemical composition and mechanical properties on the EN 10204 Type 3.1 certificates matched API 5CT specifications precisely. Yield came in at 574 MPa. Shipment was ready 11 days after confirmation, giving us a 4-day buffer before our vessel loading date.

James Wilson

United Kingdom

verified purchases

2025-06-29

Excellent L80 Tubing for Sour Service Application
We required 40 tons of L80 tubing, 2-7/8" OD with premium gas-tight connections for an H₂S-bearing reservoir in the North Sea. Hardness results on the 3.1 certificates showed 21 HRC max, fully compliant with NACE MR0175. Phosphate coating was uniform with no bare spots. Delivery took 18 days from order confirmation to our Aberdeen yard. Technical team responded to our connection queries within hours.

Michael Johnson

United States

verified purchases

2025-07-14

Superior P110 Casing for Deep Well Program
Purchased 85 tons of P110 casing, 9-5/8" OD with BTC connections for our 14,000 ft production wells in the Permian Basin. Mill test certificates confirmed yield strength at 793 MPa, well within API 5CT PSL-2 requirements. Wall thickness measured consistently at 11.99 mm against the 11.99 mm nominal. Hydrostatic test records and full NDE documentation included. Pipe arrived in R3 lengths as requested. Second order this year.