API 5CT K55/J55 Casing Tubing
Steel Mill: TPCO, BAO STEEL, VALIN STEEL
Steel Grade/Material: J55/K55
Outer Diameter(OD): 4 1/2”-20”(114.3mm-508mm)
Wall Thickness(WT) : 9.5LB/ft-133LB/ft(5.21mm-16.13mm)
Length: R1/R2/R3
Threads: Non upset threaded end(NUE), External upset threaded end(EUE)
According to American Petroleum Institute Standard API SPEC 5CT, a specification for casing and tubing for petroleum and natural gas industries-used for wells, the steel oil casing pipe can be divided into ten types: H-40, J-55, K-55, N-80, C-75, L-80, C-90, C-95, P-110 and Q-125. Due to its relatively lower price and good strength, API J55/K55 casing and tubing have been widely used in shallow wells, geothermal wells, and water wells in the natural gas and coalbed methane. Wiho Metals is a leading API 5CT casing and tubing manufacturer and supplier, we provide not only a broad range of API 5CT J55 oilfield casing pipe and API 5CT K55 tubing but also casing coupling, perforated pipe and more. Contact us for more details with the form below.
What’s the difference between API 5CT K55 and J55?
- Chemical and mechanical property: API grade K55 has the same Chemical composition as grade J55, they both have the same yield strength, but the minimum tensile strength of K55(655 MPa or 95 KSI) is higher compared to J55(517 MPa or 75 KSI).
- API color code (bands): J55tubing end is a bright green band. The band is bright green with a white band. K55 is colored with two bright green bands with no additional band.
- Delivery: API 5CT J55 PSL2and K55 PSL2 should be normalized or normalized and tempered. If thickened, normalizing or normalizing and tempering should be added after thickening. API 5CT K55 PSL2 is the same rolling delivery with API 5CT J55 PSL1;
- Impact test: For PSL1, J55 and K55 have no requirement while for PSL2, J55 and K55 require minimum impact work 20J of the full-size specimen.
API 5CT K55/J55 Chemical Composition
| Grade | C≤ | Si≤ | Mn≤ | P≤ | S≤ | Cr≤ | Ni≤ | Cu≤ | Mo≤ | V≤ |
| API 5CT K55/J55 | 0.34-0.39 | 0.20-0.35 | 1.25-1.50 | 0.020 | 0.015 | 0.15 | 0.20 | 0.20 | / | / |
API 5CT K55/J55 Mechanical Property
| Steel Grade | Yield Strength (Mpa) | Tensile Strength (Mpa) | Total Elongation under load % |
| API 5CT K55 | 379-552 | ≥655 | 0.5 |
| API 5CT J55 | 379-552 | ≥517 | 0.5 |
API 5CT Production Tubing Size
| Nominal dimension（in） | O.D(No thickened) mm | I.D(No thickened)
（mm） |
O.D(Thickened)
mm |
I.D(Thickened)
mm |
Coupling O.D(No thickened)
mm |
Coupling O.D
thickened) mm |
| 1 1/2 | 48.3 | 40.3 | 53.2 | 40.3 | 55 | 63.5 |
| 2 3/8 | 60.3 | 50.3 | 65.9 | 50.3 | 73 | 78 |
| 2 7/8 | 73.0 | 62.0 | 78.6 | 62.0 | 89.5 | 93 |
| 3 1/2 | 88.9 | 75.9 | 95.25 | 75.9 | 107 | 114.5 |
| 4 | 101.6 | 88.6 | 107.95 | 88.6 | 121 | 127 |
| 4 1/2 | 114.3 | 100.3 | 120.65 | 100.3 | 132.5 | 141.5 |
API 5CT Production Casing Size
| O.D mm(in) | Coupling O.D
(mm) |
I.D
(mm) |
Size (mm) | O.D mm(in) | Coupling O.D
(mm) |
I.D
(mm) |
Size (mm) |
| 114.3
（4 1/2） |
127.0 | 103.9 | 100.7 | 177.8
（7） |
194.5 | 166.1 | 162.9 |
| 102.9 | 99.7 | 164.0 | 160.8 | ||||
| 101.6 | 98.4 | 161.7 | 158.5 | ||||
| 99.6 | 96.4 | 159.4 | 156.2 | ||||
| 127
（5） |
141.3 | 115.8 | 112.6 | 193.7
（7 5/8） |
215.9 | 178.5 | 175.3 |
| 114.1 | 111.0 | 177.0 | 173.8 | ||||
| 112.0 | 108.8 | 174.6 | 171.5 | ||||
| 108.6 | 105.4 | 171.8 | 168.7 | ||||
| 139.7
（5 1/2） |
153.7 | 127.3 | 124.1 | 219.1
（8 5/8） |
244.5 | 205.7 | 202.5 |
| 125.7 | 122.6 | 203.7 | 200.5 | ||||
| 124.3 | 121.1 | 201.2 | 198.0 | ||||
| 121.4 | 118.2 | 198.8 | 195.6 |
