Casing & Tubing
Standard:
API SPEC 5CT Standard of American Petroleum Institute
API SPEC 5CT Standard of American Petroleum Institute
Steel Grade:
J55, K55, N80, L80, N80-1, N80Q P110 etc．
Diamensional tolerances:
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Types of steel tubes
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Outer diameter
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Wall thickness
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|
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Cold-rolled tubes
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Tube sizes
(mm) |
Tolerances(mm)
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Tolerances(mm)
|
|
＜114.3
|
±0.79
|
－12.5％
|
|
|
≥114.3
|
－0.5％, ＋1％
|
||
Mechanical properties:
|
Standard codes
|
Models of steel tubes
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Tensite strength(MPa)
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Yield strength(MPa)
|
Elongation(％)
|
Hardness
|
|
API SPEC 5CT
|
J55
|
≥517
|
379～552
|
check the table
|
|
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K55
|
≥517
|
≥655
|
|
||
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N80
|
≥689
|
552～758
|
|
||
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L80(13Cr)
|
≥655
|
552～655
|
≤241HB
|
||
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P110
|
≥862
|
758～965
|
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