API 5CT N80-1/N80-Q Casing Pipe
Steel Mill: TPCO, BAO STEEL, VALIN STEEL
Steel Grade/Material: N80
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. API-5CT N80 oilfield casing pipe includes N80-1 and N80-Q types, which are absolutely consistent regarding the chemical composition and mechanical properties, they are just various in the heat treatment, as well as the color ribbon at the ends. Wiho metals is a leading API 5CT casing and tubing manufacturer and supplier, we provide not only a broad range of API 5CT N80-1/N80-Q oilfield casing pipes but also casing coupling, perforated pipe and more. Contact us for more details with the form below.
What’s the difference between API 5CT N80-1/N80-Q?
API grade N80 -1 has the same Chemical composition as grade N80-Q, they both have the same yield strength, tensile strength, and elongation, their difference is mainly:
- Heat treatments: API 5CT Grade N80 type 1 steel pipe is treated by normalizing and tempering and N80 type Q is treated by quenching and tempering. The collapsing strength and internal pressure strength of N80-Q are higher than that of N80-1 correspondingly.
- API color code (bands): API 5CT N80-1 is a bright red band while N80-Q is a bright red band and a green band. The coupling of N80-1 is an entire red coupling and the N80-Q is an entire red coupling + a green band.
API 5CT N80 Chemical Composition
| Grade | C | Si | Mn | P | S | Cr | Ni | Cu | Mo |
| N80 type 1/Q | 0.34-0.38 | 0.20-0.35 | 1.45-1.70 | 0.020 | 0.015 | 0.15 | / | / | / |
API 5CT N80 Mechanical Property
| Grades | Yield Strength (Mpa) | Tensile Strength (Mpa) | Elongation under load, % |
| N80 type 1/Q | 552-758 | 689 | 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 |
