Welcome to ALLLAND Steel Pipe Co., Ltd.

ALLLAND Boiler Steel Pipe Supply

OCTG Tubing

Welcome to ALLLAND Steel Pipe Manufacturing. We specialize in the production and R&D of OCTG Tubing, with products widely applied in oil and gas extraction projects across diverse scenarios. All products are strictly manufactured in compliance with API 5CT standards, covering multiple steel grades. We operate our own seamless pipe production lines, enabling OCTG Tubing to be manufactured according to your specifications—including chamfering, threading, and other customizations. Every product undergoes rigorous inspection covering chemical composition, mechanical properties, non-destructive testing, hydrostatic testing, and more, ensuring pipeline reliability. For any inquiries, please contact us.

Alllandsteel is a steel pipe manufacturer based in China with 25 years of experience. The facility spans 22,000 square meters, represents a RMB 700 million investment, and operates four production lines (JCOE, ERW, SMLS, SSAW) alongside five coating lines. With an annual production capacity of 250,000 tons, the factory covers specifications ranging from Ø406 to Ø1524 and holds multiple international certifications (API/ASTM/EN/ISO/JIS). Focused on steel pipes, creating value for you!

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OCTG Tubing serves as critical work pipes for natural gas and petroleum extraction, primarily transporting oil and gas to the surface. Due to prolonged exposure to high-temperature, high-pressure, and corrosive environments, stringent requirements are placed on the pipes’ chemical and physical properties. OCTG Tubing generally adheres to the API 5CT international production standard and is widely used in oil and gas operations, including deepwater wells.

OCTG Tubing Specifications

O.D.:

1.05“ – 4 1/2” universal sizes

W.T.:

2.87 – 12.65 mm (varies by OD and steel grade)

Length:

R1 / R2 / R3 (6.10-14.63m)

Standards:

API 5CT / ISO 11960

Steel Grades:

J55 / K55 / N80 / L80 / P110

Pipe Ends:

 EUE / NUE / Premium Connection

Process & Material:

Seamless Process, Carbon Steel, Alloy Steel

Surface: 

Bare / Black / Phosphated / Varnished  

OCTG Tubing by ALLLAND

Allland Steel Pipe Factory controls the chemical composition of OCTG tubing materials from the smelting stage, ensuring long-term stable performance.
Alllandsteel’s seamless manufacturing process is highly refined, delivering high pressure-bearing capacity and uniform wall thickness.
Our pipes undergo rigorous heat treatment to enhance mechanical properties and reduce fracture risks.
Threading is performed using specialized threading machinery, not conventional cutting, ensuring long-term sealing integrity.
Non-destructive testing includes UT/EMI/hydrostatic testing, guaranteeing zero defects upon shipment.

OCTG Tubing Size Chart

Below is the outer diameter-wall thickness reference table for commonly used OCTG tubing sizes. Outer diameter range: 1.05“–4 1/2”. Suitable for most well environments. Sizes comply with API 5CT standards; customization available for special requirements. For any questions or requests, please contact us.

Nominal Size (in)Outer Diameter OD (mm)Wall Thickness WT (mm)Typical Weight (kg/m)Common Steel Grades
1.05″26.672.87 – 3.911.66 – 2.21J55 / K55 / N80
1.315″33.43.38 – 4.552.40 – 3.27J55 / K55 / N80
1.66″42.163.56 – 4.853.38 – 4.67J55 / K55 / N80
1.9″48.263.68 – 5.084.24 – 5.95J55 / K55 / N80 / L80
2 3/8″60.324.24 – 6.456.14 – 9.73J55 / K55 / N80 / L80
2 7/8″73.024.83 – 7.018.65 – 12.60J55 / K55 / N80 / L80
3 1/2″88.95.49 – 7.6212.95 – 17.26J55 / K55 / N80 / L80 / P110
4″101.65.74 – 8.5616.34 – 24.08J55 / K55 / N80 / L80 / P110
4 1/2″114.36.35 – 9.6521.79 – 32.59N80 / L80 / P110

Explanation of Different Grades for OCTG Tubing

API 5CT standards encompass multiple steel grades, with J55 / K55 / N80 / L80 / P110 being the most common. Each standard corresponds to distinct application scenarios and varying temperature and pressure limitations. Below is an overview of OCTG tubing by steel grade to facilitate your selection.

J55 / K55:

Primarily used in conventional oil and gas wells, onshore wells, and shallow wells, this is the most widely applied steel grade.

Yield Strength: ≥ 379 MPa

Temperature Range: –20°C to 120°C

Pressure Range: Low-to-medium pressure

Characteristics: Commonly made of carbon steel or alloy steel, offering low cost and stable performance, suitable for large-scale projects

N80:

Used in medium-to-deep oil wells requiring moderate pressure resistance.

Yield Strength: ≥ 552 MPa

Temperature Range: –20°C to 150°C

Pressure Range: Medium-to-high pressure

Features: Made from medium-carbon low-alloy steel, offering adequate pressure resistance and good stability.

L80:

Used in corrosive oil and gas wells containing carbon dioxide and hydrogen sulfide, offering corrosion resistance.

Yield Strength: 552–620 MPa

Temperature Range: –20°C to 180°C

Pressure Range: Medium-High Pressure

Characteristics: Strictly controlled chemical composition provides excellent resistance to hydrogen sulfide corrosion and reduces hydrogen embrittlement risk.

P110:

This steel grade is used in ultra-deep wells under high-temperature and high-pressure conditions.

Yield strength: ≥ 758 MPa

Temperature range: –20°C to 200°C and above

Pressure range: High-pressure to ultra-high-pressure

Characteristics: Extremely high pressure-bearing capacity, suitable for extreme environments.

OCTG Tubing Applications

Crude Oil Production Wells: Transports petroleum from underground to surface. These wells are relatively shallow and require reliable threaded connections to ensure pipeline integrity. OCTG Tubing meets threaded connection requirements while offering exceptional stability.
Natural Gas Wells: Natural gas exists as a liquid underground. OCTG Tubing must withstand high pressure and maintain excellent sealing performance. Particularly in gas-liquid mixtures, high temperature and pressure are key performance metrics. Both N80 and L80 grades within OCTG Tubing meet these demands.
High-Pressure Wells: High-pressure well operations are more complex. Beyond withstanding pressure, considerations include temperature fluctuations caused by pressure and axial load capacity, presenting intricate challenges. The P110 high-strength steel grade in OCTG tubing, coupled with its strict tolerances, can adapt to such conditions.
Corrosive Wells: Handling pressure and load-bearing capacity, corrosive elements are also common in oil and gas wells. The L80 grade and special corrosion-resistant alloys in OCTG tubing can withstand corrosive wells containing hydrogen sulfide and carbon dioxide.
Offshore and Deepwater Wells: Offshore operations demand consideration of pressure, dynamic loads, and corrosion resistance, alongside stringent manufacturing requirements. OCTG Tubing’s P110 premium custom steel delivers extended service life.