The seven catalogue families
OCTG — oil country tubular goods — is the family of pipe and accessories that goes into an oil or gas well: casing that lines and supports the borehole, tubing that carries produced fluids to surface, and the couplings, pup joints and crossovers that join and adjust those strings. If you are building a material list for a drilling programme, start from the string you need to run, then work down to grade and thread.
The company catalogue behind this site lists 71 product entries across seven live families: oil casing, oil tubing, premium thread processing, pup joints, couplings, crossovers and the 13Cr corrosion-resistant series. Couplings are the largest family in the catalogue — 26 of its 71 entries. Sizes and grades quoted on this site come from the company's published range; anything outside that range is confirmed in writing before an order is accepted.
The range at a glance
| Family | Published range | Go to |
|---|---|---|
| Casing pipe | Sizes 4-1/2 in to 20 in (size list); grades J55, K55, N80, L80, P110 (grade list — a separate list) | Casing Pipe page |
| Oil tubing | 1.05 in to 3-1/2 in listed sizes; EUE and NUE ends | Oil Tubing page |
| Couplings | Tubing and casing; BTC, LTC, STC, EUE, NUE, special clearance | Tubing Couplings page |
| Pup joints | Casing and tubing patterns; perforated subs by enquiry | Pup Joints page |
| Crossovers | Tubing crossovers and conversion joints | Crossovers page |
| Premium connections | Gas-tight thread processing incl. BGT and TPJC patterns | Premium Connections page |
| 13Cr series | L80-13Cr casing and tubing for CO2 service | 13Cr page |
How a specification becomes a quotation
A useful OCTG enquiry contains five things: outside diameter, wall thickness or weight, steel grade, thread and coupling type, and length range — plus quantity and destination port. With those five points stated, ask for MOQ, packing and lead time to be confirmed for that exact specification in the written quotation. Without them, any price is a guess. Use the RFQ form on this page or on the contact page, and state those five points in it.
Threading and inspection are done as part of the order, not as an afterthought. The company's product pages describe CNC lathes, CNC make-up equipment, automatic flaw detection, hydrostatic testing, automatic marking and painting equipment, and ultrasonic thickness measurement. Coupling production is described with phosphating of internal and external surfaces, magnetic particle inspection and marking in accordance with API Spec 5CT, with PSL1, PSL2 and PSL3 processing available for coupling orders. Those process details matter: the phosphate layer and the mark are part of the coupling as specified.
Standards, stated plainly
Products on this site are described as manufactured and inspected in accordance with API Spec 5CT, and the company states that it operates an ISO 9001 quality management system. Certificates are available upon request. Certificate numbers are not printed on this site. If your tender requires documentary evidence, request it with your enquiry: the quotation states which certificates and filing documents are available for your specification, so the evaluation rests on the documents themselves.
Who buys from this factory
The company describes its domestic service as supplying major Chinese oilfield regions and states long-term supply relationships in South Asia, Southeast Asia, the Middle East, Europe, Africa and South America, including named relationships with buyers in Saudi Arabia, the United Arab Emirates, Sudan, Kuwait and Turkey in its product literature. Export orders are handled under the company's own import and export registration, filed in Tianjin. Whether you are a stockist building a coupling inventory, a distributor filling a framework agreement or a contractor buying against a drilling schedule, the route is the same: send the specification in the enquiry; inspection and packing for the order are confirmed in the quotation before production.
What is the difference between casing and tubing?
Casing is published in the larger diameters that line the well, from 4-1/2 in to 20 in, in STC, LTC and BTC threads. Tubing is published in the production string sizes with EUE or NUE ends. If you are unsure which string a size belongs to, read the blog article on casing versus tubing, then send your well diagram with the RFQ.
Can I order couplings and pup joints without pipe?
Yes, as an enquiry. Couplings are the largest family in the catalogue and pup joints and crossovers are listed as independent families, so an accessory-only enquiry can be sent on its own lines. State size, grade and thread exactly as they appear on your pipe order so the accessories gauge to the same specification, and the quotation will confirm whether the accessory lines can be accepted and in what scope.
Do you publish MOQ and lead time?
MOQ and lead time are confirmed in each written quotation for the specification, rather than published as a generic promise. Common coupling sizes are described by the company as stocked items; confirm current availability when you enquire.
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.