An overview of  API tubing grade and specifications

API Tubing Grade & Specifications API tubing, also known as oil country tubular goods (octg), plays a crucial role in the Oil and gas industry. It is used for the extraction of oil and gas from wells, providing a conduit for the fluids to flow to the surface. To ensure the safe and efficient operation of these wells, it is essential to understand the different grades and specifications of API tubing. API tubing grades are standardized by the american petroleum institute (API) to ensure quality and consistency across the industry. These grades are classified based on their mechanical properties, such as yield strength, tensile strength, and hardness. The most commonly used grades are api 5ct J55, api 5ct k55, api 5ct n80, and api 5ct l80. API 5CT J55 is a low-cost grade with a yield strength of 55,000 psi. It is suitable for shallow wells and low-pressure applications. API 5CT K55 has similar properties to J55 but with a higher tensile strength of 75,000 psi. This grade is commonly used in medium-depth wells.

API 5CT N80 is a higher-grade tubing with a yield strength of 80,000 psi. It is suitable for deeper wells and higher-pressure applications. N80 tubing is known for its excellent resistance to corrosion and cracking, making it a popular choice in harsh environments.

API 5CT L80 Casing tubing range lengths
	Range 1	Range 2	Range 3
CASING (PE/T and C/SF)
Total range length, inclusive Permissible variation, max a	4.88 to 7.62 1.83	7.62 to 10.36	10.36 to 14.63 1.83
		1.52
TUBING AND CASING USED AS TUBING
(PE/T and C/SF)
Total range length, inclusive Permissible variation, max a	6.10 to 7.32 b	8.53 to 9.75 c	11.58 to 12.80 d
	0.61	0.61	0.61
INTEGRAL TUBING connectionS (including IJ/PE
and IJ/SF)
Total range length, inclusive Permissible variation, max a	6.10 to 7.92 e	8.53 to 10.36	11.58 to 13.72 0.61
	0.61	0.61
PUP JOINTS	Lengths: 0.61; 0.91; 1.22; 1.83; 2.44; 3.05 and 3.66 e
	Tolerance: ±0.076
a Length variation applies to rail car shipment to the point of use and does not apply to order items of less than 18,144 kg of Pipe.
b By agreement between purchaser and manufacturer, the maximum length may be increased to 8.57 m.
c By agreement between purchaser and manufacturer, the maximum length may be increased to 10.76 m.
d By agreement between purchaser and manufacturer, the maximum length may be increased to 17.72 m.0.61 m pup joints may be furnished up to 0.91 m long by agreement between purchaser and manufacturer, and lengths other than those listed may be furnished by agreement between purchaser and manufacturer.

API 5CT L80 is a higher-grade tubing with a yield strength of 80,000 psi. It has similar properties to N80 but with enhanced mechanical properties. l80 tubing is commonly used in wells with high levels of CO2 and H2S, as it has excellent resistance to corrosion and sulfide stress cracking. In addition to the grades, API tubing specifications also play a crucial role in determining the suitability of the tubing for specific applications. These specifications cover various aspects, including dimensions, chemical composition, and testing requirements. API tubing specifications are classified into different groups, such as Group 1, Group 2, and Group 3. Group 1 specifications are the most basic and have the least stringent requirements. They are suitable for general-purpose applications. Group 2 specifications have additional requirements, such as stricter chemical composition limits and more rigorous testing. They are suitable for more demanding applications. Group 3 specifications have the highest requirements and are typically used in critical applications, such as deepwater drilling. Apart from the grade and specifications, API plastic Lip Gloss Tube