b Nominal linear masses, threaded and coupled (Column 4) are shown for information only.
c The densities of martensitic chromium steels (l80types 9Cr and 13Cr) are less than those of carbon steels; The masses shown are therefore not accurate for martensitic chromium steels; A mass correction factor of 0.989 shall be used.
d Mass gain or loss due to end finishing; See 8.5.
e Drift diameter for most common bit size; This drift diameter shall be specified in the purchase agreement and marked on the Pipe; See 8.10 for drift requirements.
f Based on 758 mPa minimum yield strength or greater.
g Based on 379 mPa minimum yield strength.
The j55, K55, and N80 designations in the API SPEC 5CT standards refer to differentgrades of steel used in the manufacturing of seamless tubing and casing. Each grade has specific chemical composition and mechanical properties thatmake it suitable for different operatingconditions.
Carbon Steel Seamless Pipe
J55 is a commonly used grade for tubing and casing. It has a minimum yield strength of 55,000 psi and a minimum tensile strength of 75,000 psi. This grade is suitable for shallow to medium-depth wells with low to moderate pressure and temperature conditions.
K55 is another widely used grade that has similar mechanical properties to J55. However, it has a higher tensile strength of 95,000 psi, making it suitable for deeper wells with higher pressure and temperature conditions.
N80 is a higher-grade steel that offers enhanced mechanical properties compared to J55 and K55. It has a minimum yield strength of 80,000 psi and a minimum tensile strength of 95,000 psi. This grade is suitable for more demanding applications, such as high-pressure and high-temperature wells.
The API SPEC 5CT J55 K55 N80 standards also specify the dimensions and tolerances for seamless tubing and casing. These include the outer diameter, Wall thickness, and length of the products. The standards ensure that the products are manufactured to precisespecifications, allowing for proper fit and function in the wellbore.
In addition to the material and dimensional requirements, the API SPEC 5CT standards also define the testing and inspectionprocedures for seamless tubing and casing. These procedures ensure that the products meet the specified mechanical properties and are free from defects that could compromisetheirperformance.
Manufacturers of seamless tubing and casing must adhere to the API SPEC 5
Seamless tubing and casing are essential components in oil and gas wells. They provide structural support and serve as conduits for the extraction of oil and gas from the reservoir to the surface. The API SPEC 5CT J55 K55 N80 standards define the requirements for the Materials, dimensions, and mechanical properties of these products.
