Definition - What does Tubing Grade mean?
Tubing Grade is the grade given by the American Petroleum Institute (API) for designing, manufacturing and installation of oil and gas pipelines. API is the trade association which sets international standards for tubing. The tubes or pipelines are made up from different types of steel based on different climate conditions where they are to be installed. The proper grade system makes the minimum specification and requirement of a tube to be used in a certain working condition. It is a standard recommendation of the authority.
Petropedia explains Tubing Grade
The grades for pipelines are globally set by API as per the international standards of tubing. Some of the tubing grades used in the petroleum industry are as follows:
- J55 – For shallow and low pressure wells, the most recommended grade for tubing is J55.
- L80 – This is used in three different versions as Type 1, 9 Cr and 13 Cr. L80 13 Cr is popular as it has good CO2 induced weight loss corrosion.
- C90 – This grade has to be specially ordered by the organization as it is a relatively new API grade. It is available in two types: Type 1 and Type 2. Type 1 is mostly used in sour services.
- T-95 – This tubular grade is a superior version of C90 and is also used for sour services.
- N80 – It is used in the sweet oil and gas wells. It is a relatively old grade.
- H40 – Its yield strength is very low and hence is not used in tubing sizes.
- C75 – It is not used nowadays as it is no longer an API standard.
- P110 & Q125 are other two tubing grades.