Couplings are used to hold the neighboring joints together during axial tension or compression.The common oilfield API-5CT casing couplings include J55, K55, N80 and P110 in accordance with API 5CT/5B, can be classified as STC (short thread), LTC (long thread) BTC (buttress thread) and premium connections.
We cover a size from 4-1/2″ to 20″,STC, LTC and BTC, we also manufacture premium connections based on our customer enquiry.
We provide LTC casing coulings from 4-1/2″ to 20″, in grade J55, K55, N80, L80 and P110.
Threads are used as mechanical means to hold the neighboring joints together during axial tension or compression. For all casing sizes, the threads are not intended to be leak resistant when made up.
The round-thread (STC or LTC) casing-joint strength is given as the lesser of the fracture strength of the pin and the jump-out strength.
1. Size: 4-1/2″ ~ 20″
2. Standard: API 5CT/5B
3. Type: LTC
4. Grade:J55/K55/N80/L80/P110
5. Packaging: wooden pallet, tight wrapped /W paper carton
PI Tubing Couplings
We carry size range of 2-3/8”, 2-7/8″, 3-1/2″,4″ and 4-1/2″ in J55, K55, N80, P110 grade. All of our couplings meet the API Specifications 5CT/5B.
Couplings are short lengths of pipe used to connect 2 joints of tubing or casing.
Designed in accordance with API 5CT/5B and are made of good seamless steel. EUE petroleum tubing coupling cover the outer diameter from 77.80mm to 141.30mm, that is bigger than the outer diameter of the non upset threaded end product.
API NUE Tubing Couplings
Designed in accordance with API 5CT/5B and are made of good seamless steel. NUE tubing coupling possesses the outer diameter range from 73.02 to 132.08mm.
API NUE Tubing Coupling
We carry size range of 2-3/8”, 2-7/8″, 3-1/2″,4″ and 4-1/2″ in J55, K55, N80, P110 grade. All of our couplings meet the API Specifications 5CT/5B.


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Continental Steel Co.,Ltd(CSC) is a pioneering manufacturer, stockist, and supplier of steel pipe products.