Product introduction
API-5CT K55 oilfield casing pipe is very similar to J55, there is no significant difference in the chemical composition
and yield strength, however the ultimate tensile strength of K55 is higher than J55 steel, K55/J55 are 655MPa and
517MPa respectively.
K55 has better mechanical and thermal fatigue resistance and crack resistance than J55. For a thermal production well,
the heavy wall K55 casing is appropriate instead of J55 casing. The former has a better thermal fatigue resistance property
than the latter.
Inspection
Physical properties are checked and each length hydrostatically tested, normally to only 3,000 psi in the plain end (unthreaded) condition.
The following are also checked:
Dimensions
Weights
Straightness
Lengths
Part of this inspection is to drift all lengths.
Despite all the American Petroleum Institute (API) specifications and testing, some tubing defects are still found after delivery; thus, some operators
do further inspection.
Inspection Method:
Size and surface inspection
NDT and pressure test and third party certication
Hydrostatic
Drifting test
Physical and chemicail analysis
Hardness and pressure test.
Electromagnetic
Magnetic particle
Ultrasonic
Technical data
Dimensions And Weight
| Size | Weight | Outside Diameter | Wall Thickness | End Finish | ||||||
| Grade | ||||||||||
| in | mm | in | mm | J55K55 | L80 | N80 | C90T95 | P110 | ||
| 4 1/2 | 9.50 | 4.500 | 114.3 | 0.205 | 5.21 | PS | – | – | – | – |
| 10.50 | 0.224 | 5.69 | PSB | – | – | – | – | |||
| 11.60 | 0.250 | 6.35 | PSLB | PLB | PLB | PLB | PLB | |||
| 13.50 | 0.290 | 7.37 | – | PLB | PLB | PLB | PLB | |||
| 15.10 | 0.337 | 9.56 | – | – | – | – | PLB | |||
| 5 | 11.50 | 5.00 | 127.00 | 0.220 | 5.59 | PS | – | – | – | – |
| 13.00 | 0.253 | 6.43 | PSLB | – | – | – | – | |||
| 15.00 | 0.296 | 7.52 | PSLB | PLB | PLB | PLBE | PLB | |||
| 18.00 | 0.362 | 9.19 | – | PLB | PLB | PLBE | PLB | |||
| 21.40 | 0.437 | 11.10 | – | PLB | PLB | PLB | PLB | |||
| 23.20 | 0.478 | 12.14 | – | PLB | ||||||
| 24.10 | 0.500 | 12.70 | – | PLB | ||||||
| 5 1/2 | 14.00 | 5.500 | 139.7 | 0.244 | 6.20 | PS | – | – | – | – |
| 15.50 | 0.275 | 6.98 | PSLB | – | – | – | – | |||
| 17.00 | 0.304 | 7.72 | PSLB | PLB | PLB | PLBE | PLB | |||
| 20.00 | 0.361 | 9.17 | – | PLB | PLB | PLBE | PLB | |||
| 23.00 | 0.415 | 10.54 | – | PLB | PLB | PLBE | PLB | |||
| 6 5/8 | 20.00 | 6.625 | 168.28 | 0.288 | 7.32 | PSLB | – | – | – | – |
| 24.00 | 0.352 | 8.94 | PSLB | PLB | PLB | PLBE | PLB | |||
| 28.00 | 0.417 | 10.59 | – | PLB | PLB | PLBE | PLB | |||
| 32.00 | 0.475 | 12.06 | – | PLB | PLB | PLBE | PLB | |||
| 7 | 17.00 | 7.00 | 177.80 | 0.231 | 5.87 | – | – | – | – | – |
| 20.00 | 0.272 | 6.91 | PS | – | – | – | – | |||
| 23.00 | 0.317 | 8.05 | PSLB | PLB | PLB | PLBE | – | |||
| 26.00 | 0.362 | 9.19 | PSLB | PLB | PLB | PLBE | PLB | |||
| 29.00 | 0.408 | 10.36 | – | PLB | PLB | PLBE | PLB | |||
| 32.00 | 0.453 | 11.51 | – | PLB | PLB | PLBE | PLB | |||
| 35.00 | 0.498 | 12.65 | – | PLB | PLB | PLBE | PLB | |||
| 38.00 | 0.540 | 13.72 | – | PLB | PLB | PLBE | PLB | |||
| 7 5/8 | 24.00 | 7.625 | 193.68 | 0.300 | 7.62 | – | – | – | – | – |
| 26.40 | 0.328 | 8.33 | PSLB | PLB | PLB | PLBE | PLB | |||
| 29.70 | 0.375 | 9.52 | – | PLB | PLB | PLBE | PLB | |||
| 33.70 | 0.430 | 10.92 | – | PLB | PLB | PLBE | PLB | |||
| 39.00 | 0.500 | 12.70 | – | PLB | PLB | PLBE | PLB | |||
| 42.80 | 0.562 | 14.27 | – | PLB | PLB | PLB | PLB | |||
| 45.30 | 0.595 | 15.11 | – | PLB | PLB | PLB | PLB | |||
| 47.10 | 0.625 | 15.88 | – | PLB | PLB | PLB | PLB | |||
| 8 5/8 | 24.00 | 8.625 | 219.08 | 0.264 | 6.71 | PS | – | – | – | – |
| 28.00 | 0.304 | 7.72 | – | – | – | – | – | |||
| 32.00 | 0.352 | 8.94 | PSLB | – | – | – | – | |||
| 36.00 | 0.400 | 10.16 | PSLB | PLB | PLB | PLBE | PLB | |||
| 40.00 | 0.450 | 11.43 | – | PLB | PLB | PLBE | PLB | |||
| 44.00 | 0.500 | 12.70 | – | PLB | PLB | PLBE | PLB | |||
| 49.00 | 0.557 | 14.15 | – | PLB | PLB | PLBE | PLB | |||
| 9 5/8 | 32.30 | 9.625 | 244.48 | 0.312 | 7.92 | – | – | – | – | – |
| 36.00 | 0.352 | 8.94 | PSLB | – | – | – | – | |||
| 40.00 | 0.395 | 10.03 | PSLB | PLB | PLB | PLBE | – | |||
| 43.50 | 0.435 | 11.05 | – | PLB | PLB | PLBE | PLB | |||
| 47.00 | 0.472 | 11.99 | – | PLB | PLB | PLBE | PLB | |||
| 53.50 | 0.545 | 13.84 | – | PLB | PLB | PLBE | PLB | |||
| 58.40 | 0.595 | 15.11 | – | PLB | PLB | PLB | PLB | |||
| 10 3/4 | 32.75 | 10.75 | 273.05 | 0.279 | 7.09 | – | – | – | – | – |
| 40.50 | 0.350 | 8.89 | PSB | – | – | – | – | |||
| 15.50 | 0.400 | 10.16 | PSB | – | – | – | – | |||
| 51.00 | 0.450 | 11.43 | PSB | PSB | PSB | PSBE | PSB | |||
| 55.50 | 0.495 | 12.57 | – | PSB | PSB | PSBE | PSB | |||
| 60.70 | 0.545 | 13.84 | – | – | – | PSBE | PSB | |||
| 65.70 | 0.595 | 15.11 | – | – | – | PSB | PSB | |||
| 13 3/8 | 48.00 | 13.375 | 339.73 | 0.330 | 8.38 | – | – | – | – | – |
| 54.50 | 0.380 | 9.65 | PSB | – | – | – | – | |||
| 61.00 | 0.430 | 10.92 | PSB | – | – | – | – | |||
| 68.00 | 0.480 | 12.19 | PSB | PSB | PSB | PSB | PSB | |||
| 72.00 | 0.514 | 13.06 | – | PSB | PSB | PSB | PSB | |||
| 16 | 65.00 | 16 | 406.40 | 0.375 | 9.53 | – | – | – | – | – |
| 75.00 | 0.438 | 11.13 | PSB | – | – | – | – | |||
| 84.00 | 0.495 | 12.57 | PSB | – | – | – | – | |||
| 109.00 | 0.656 | 16.66 | P | P | P | – | P | |||
| 18 5/8 | 87.50 | 18.625 | 473.08 | 0.435 | 11.05 | PSB | – | – | – | – |
| 20 | 94.00 | 20 | 508.00 | 0.438 | 11.13 | PSLB | – | – | – | – |
| 106.50 | 0.500 | 12.70 | PSLB | – | – | – | – | |||
| 133.00 | 0.635 | 16.13 | PSLB | – | – | – | – | |||
| Chemical Properties | |||||||||
| Carbon | Silicon | Manganese | Phosphorous | Sulphur | Molybdenum | Nickel | Chromium | Copper | Others |
| – | – | – | 0.03 | 0.03 | – | – | – | – | – |
| Mechanical Properties | |||||||||
| Yield Strength | Tensile Strength | Elongation A5 min | |||||||
| MPa min | ksi min | MPa min | MPa min | ksi min | Percentage | ||||
| 655 | – | 95 | – | ||||||
