API 5CT 5 1/2" N80 BTC premium thread Casing Coupling
Api 5ct casing coupling
Casing coupling is a kind of oil field drilling tool, which is mainly used for tubing connection.The coupling mainly solves the problem of fatigue fracture caused by stress concentration.
The coupling is divided into tubing coupling and casing coupling.
Tubing Coupling
Tubing coupling specifications | OD mm | Min length mm | Weight kg | |||
NU | EN | NU | EN | NU | EN | |
1.9 | 55.88 | 63.5 | 93.25 | 98.42 | 0.56 | 0.84 |
2 3/8 | 73.02 | 77.8 | 107.95 | 123.82 | 1.28 | 1.55 |
2 7/8 | 88.9 | 93.17 | 130.18 | 133.35 | 2.34 | 2.4 |
3 1/2 | 107.95 | 114.3 | 142.88 | 146.05 | 3.71 | 4.1 |
4 | 120.65 | 127 | 146.05 | 152.4 | 4.35 | 4.82 |
4 1/2 | 132.08 | 141.3 | 155.58 | 158.75 | 4.89 | 6.05 |
Casing Coupling
Casing coupling specifications | OD mm | Min length mm | Weight kg | ||
short-thread | long-thread | short-thread | long-thread | ||
4 1/2 | 127 | 158.75 | 177.8 | 3.62 | 4.15 |
5 | 141.3 | 165.1 | 196.85 | 4.66 | 5.75 |
5 1/2 | 153.67 | 171.45 | 203.2 | 5.23 | 6.42 |
Performance of Internal Epoxy Coating
| Inspection Item | Standard | Inspection Method | ||
| 1 | Appearance | Smooth, Uniform color, no bubble, no cracking or contraction cavity, little range peel allowed | Visual | |
| 2 | Thermal Performance |ΔT g|(ºC ) | ≤ 5 | Appendix B | |
| 3 | cathodic disbanding resistance | ≤ 6.5 | Appendix C | |
| 24h or 48h (mm) | ||||
| 4 | Bonding surface porosity | 1~4 | Appendix D | |
| 5 | The section void ratio | 1~3 | Appendix D | |
| 6 | resistance to deflection 3° | No cracking | Appendix E | |
| 7 | Impact Energy (8J) | No pin hole | Appendix F | |
| 8 | Adhesive force | dissection method | 1~2 | Appendix G |
| pull off adhesion (MPa) | ≥ 20 | GB/T 5210 | ||
| 9 | Electric strength (MV/m) | ≥ 30 | GB/T 1408.1 | |
| 10 | Volume resistivity(Ω·m ) | ≥ 1×1013 | GB/T 1410 | |
| 11 | Salt fog resistance (1000h) | No change of anti-corrosion coating | GB/T 1771 | |
All of casing couplings are with materials of steel grade including J55, K55, N80, N80-1,N80-Q,L80,P110 and so on . The casing couplings have two types, namely NU and EU. By numerically controlled lathe and import molding cutter, the processing of thread can be finished in one time,which ensures its commonality and interchangeability. We have complete testing abilities, adopting a whole set of single testing apparatus of thread, including tape,pitch,tooth depth and profile.
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.
1.Material:J55, K55, N80-1, N80-Q, L80, C90, P110
2.Size: tubing coupling from 2-3/8" to 4-1/2"
3.Surface treatment: Whole phosphating, or inside phosphating and outside coating
4.Packing: By carton, wooden case, wooden pallet, or by requirements of customers
