Standards guide
API 5CT Casing Grade Comparison
A practical RFQ guide for J55, K55, N80, L80 and P110 casing and tubing grades.
Practical Standard Review
OCTG grade selection depends on well condition, connection type, drift requirement, length range, coupling, inspection, and traceability. Grade names alone are not enough for a reliable casing or tubing quotation.
Himount Steel reviews the ordered standard, grade, product form, dimension tolerance, inspection level, packing method, and shipment route before confirming price and lead time. Final supply always follows the buyer specification and accepted mill test certificate.
Key Ordering Points
| Main comparison | OCTG grade selection depends on well condition, connection type, drift requirement, length range, coupling, inspection, and traceability. Grade names alone are not enough for a reliable casing or tubing quotation. |
|---|---|
| Confirm in RFQ | API 5CT grade, size, weight, range, connection, coupling, drift, thread protection, and inspection |
| Risk to avoid | Thread connection and range must be confirmed together with grade to avoid wrong material preparation. |
| Documentation | Confirm MTC type, heat number traceability, inspection record, and any buyer approval wording. |
| Next step | Send the project specification or previous PO so Himount Steel can check the supply route. |
Buyer Checks Before Quotation
- Use the project specification as the authority when grade names look similar.
- Confirm product form, size, tolerance, delivery condition, and inspection plan together.
- Ask for comparable references only as RFQ aids, not automatic substitutions.
- Review certificate wording before shipment if the project has strict acceptance rules.
Related Himount Pages
Prepare A Complete Steel Inquiry
Send the product standard, grade, size list, quantity, drawings, inspection scope, certificate request, packing method, and destination port. Himount Steel will review the technical route before quotation.