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J55 K55 API 5CT Oil Well Casing Pipe | Seamless OCTG Casing Tube
- Most cost-effective general-purpose OCTG grade, widely used for surface & intermediate casing
- Strict API 5CT standard manufacturing, stable dimensional accuracy and thread interchangeability
- Multiple thread options: BTC, LC, SC, compatible with most wellsite connection tools
- Standard R1/R2/R3 lengths in stock, short delivery time for conventional well projects
- Good weldability and mechanical property, suitable for shallow to medium depth well conditions
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Product Overview
J55 and K55 are the most widely used general-purpose grades in API 5CT casing system, mainly applied as surface casing, conductor pipe and intermediate casing in shallow to medium depth oil & gas wells. They feature balanced strength, good ductility and excellent economy, and are the first choice for conventional onshore well construction and development projects.
Both grades are manufactured from high-quality carbon steel billet via hot rolling piercing + cold sizing seamless process, and produced and inspected in full compliance with API Spec 5CT and ISO 11960 standards. Available outer diameter covers 4-1/2″ to 13-3/8″ common casing sizes, with wall thickness corresponding to standard Schedule weights. Thread forms include standard buttress thread (BTC), long thread coupling (LC) and short thread coupling (SC), which can match most wellsite connection tools. Standard pipe lengths are available in R1 (4.88m), R2 (7.32m) and R3 (10.36m), and custom fixed lengths can also be supplied according to well design.
J55 / K55 API casing pipe is widely used in onshore conventional oilfields, shallow gas wells, coal-bed methane wells, geothermal wells and water injection wells. Each batch undergoes strict API standard dimensional inspection, thread gauge verification and hydrostatic pressure test before delivery, and is accompanied by official Mill Test Report for full quality traceability.
Chemical & Mechanical Property Snapshot
Detailed Technical Specifications
Dimension Range Table
Product Comparison Table
App Market
Reliable Steel Coil Solutions For Diverse Industrial Applications
Crude Oil and Natural Gas Transportation in Oil & Gas Production
Offshore Oil & Gas Well Casing and Cementing
Onshore Oilfield
Product Packaging
Secure Export Packaging For Safe Handling And Delivery
FAQs
J55 and K55 have the same yield strength range, but K55 has higher minimum tensile strength. K55 is more suitable for intermediate casing with higher tensile load requirements, while J55 is more economical for surface casing.
J55 grade is mainly used for casing. For production tubing, N80 or L80 grade is more recommended for better wear resistance and long-term production performance.
BTC (buttress thread) is the most widely used for casing due to its good tensile strength and sealing performance. LC and SC threads are also available for specific well designs.
Yes. In addition to standard R1/R2/R3 lengths, we can also provide custom fixed-length cutting according to your well depth design.
Yes. We can supply casing pipes with API standard couplings, and can also perform thread make-up before delivery according to requirements.
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