Where it fits
Well construction where L80 is specified and the project has confirmed the required hardness, connection and environmental-cracking controls.
API 5CT · OCTG grade reference
API 5CT L80 casing and tubing reference
API 5CT L80 / L80-1 / L80Q is a grade-specific reference for engineering selection and RFQ preparation. HONGFENG verifies grade suffix, dimensions, connection, test requirements and documents for each order.
Updated 13 November 2026 · HEBEI HONGFENG IMPORT & EXPORT CO.,LTD
Grade scope
How to read API 5CT L80 / L80-1 / L80Q
L80-1 and L80Q differ in heat treatment; the service environment and hardness controls must be confirmed by the project.
What not to assume
L80 should not be presented as a universal sour-service substitute. The maximum hardness, heat-treatment type, H2S/CO2 conditions and connection must be verified in the approved specification.
Mechanical snapshotReference values; project and MTC govern
| Property | Reference |
|---|---|
| Yield strength | 552–655 MPa |
| Minimum tensile strength | 655 MPa |
| Product form | Casing / tubing |
| Delivery condition | L80-1 and L80Q differ in heat treatment; the service environment and hardness controls must be confirmed by the project. |
RFQ data
What to send for L80
- Standard edition, grade and delivery suffix
- Product form and outside diameter
- Wall thickness or weight and length range
- Connection, coupling, thread or end preparation
- CVN temperature, energy or project testing
- Quantity, inspection scope, destination and date
Send the grade, dimensions and test requirements
Availability, delivery condition, test regime and documents are confirmed for the exact order. The signed contract and final MTC govern acceptance.
Related grade pages
Grade-specific technical pages
FAQ
API 5CT L80 / L80-1 / L80Q
What is the API 5CT L80 yield range?
The reference range is 552–655 MPa yield and minimum 655 MPa tensile. L80 has a narrower yield range than N80 and requires hardness control.
Is L80 always a sour-service casing?
L80 is often associated with sour-service review, but suitability still depends on the controlled specification, hardness, H2S/CO2 conditions, temperature, stress and connection.
What is the difference between L80-1 and L80Q?
Both are L80 references with different heat-treatment routes. The purchase order must state the exact suffix and any project hardness or testing requirements.