Sizes, grades and threads, published as separate lists
An oil casing enquiry names a size, a grade, a thread and a quantity tied to a well or a stocking programme, and is written out in full on the enquiry form below. Everything on this page assumes oil and gas well service; no other casing application is offered.
The published lists are stated separately: fourteen machinable casing sizes from 4-1/2 in to 20 in on the size list; the grade list naming J55, K55, N80-1, N80Q, L80-1 and P110, with chromium options through the 13Cr series named separately; and STC, LTC or BTC threads, with premium gas-tight processing in its own family. The lists are not documented against each other. Named catalogue anchors include 5 in N80 casing, J55 casing, L80-13Cr casing and 4-1/2 in LTC casing. Oil casing is quoted per programme, line by line against the full specification.
What an oil casing quotation needs from you
- Size and weight — outside diameter plus weight per foot or wall thickness, for each string section.
- Grade per section — surface, intermediate and production sections can carry different grades on one order, each section its own line.
- Thread and coupling — STC, LTC, BTC or premium pattern, with the coupling grade the design names for the line.
- Length range — Range 1, 2 or 3, and any minimum average length requirement in your tender.
- Quantity and delivery point — joints or tonnage, plus port or site, so packing and freight are quoted on the same basis.
With those five lines stated in the enquiry, ask for price, MOQ for the specification, packing method and lead time to be confirmed for the order in the written quotation. The company's casing literature describes packing by steel strap or steel frame, or as agreed — for long sea transits, agree the packing and thread protector specification in the order, because protectors safeguard the threads the whole string depends on. Thread protectors, in particular, should be named: steel or composite, full-length or end-only.
Grades in oil casing service — the short version
The published list names J55, K55, N80, L80-1 and P110, and the design assigns a grade to each section. The company's N80 data for its named 5 in casing sample lists yield strength of 552 to 758 MPa and tensile strength of 689 MPa. Any hardness limit from your specification is stated in the enquiry. Choose by interval design, then let price follow — reversing that order is how wells end up over-specified on surface pipe and under-specified at depth.
Inspection follows the order specification. The equipment described in the company's product pages — automatic flaw detection, hydrostatic testing, ultrasonic thickness measurement, automatic marking — is the plant behind the inspection documents for a casing order; which documents are provided with the order is confirmed in the quotation. State any third-party inspection requirement in the enquiry itself.
Is oil casing pipe different from casing pipe on this site?
No — the same product and the same published range: sizes from 4-1/2 in to 20 in, in STC, LTC, BTC and premium thread forms. An enquiry is written against the specific programme behind it.
Can one order cover several grades and sizes?
Send them as one enquiry: list each section as its own line with its own size, grade, thread and quantity; the quotation confirms each line — whether it can be accepted, its price and its packing — line by line.
Do you quote CIF?
Destination is an RFQ field, so the quotation can be built on the delivery basis you request. State port and terms in the enquiry so freight is calculated on the same specification as the pipe.
Request a Quotation
Send your size, grade, thread and quantity. MOQ, packing and lead time are confirmed in the quotation for your exact specification — no generic promise replaces a written quote.