API 5CT N80 Casing Pipe


  • Outer Dimensions: 6.0mm -219.0mm
  • Wall Thickness: 1.0mm -30 mm
  • Length: R1(4.88-7.62m), R2(7.62-10.36m), R3(10.36-14.63m)
  • Type: API 5CT N80 type 1, API 5CT N80 type Q
  • Thread type: Short round thread, Long round thread, Buttress thread
  • Application: Transportation of gas, water, oil and natural gas.

API 5CT is a specification for casing and tubing for petroleum and natural gas industries-used for wells. This Standard specifies the technical delivery conditions for steel pipes (casing, tubing and pup joints), coupling stock, coupling material and accessory material and establishes requirements for three Product Specification Levels (PSL-1, PSL-2, PSL-3). Grade N80 is an API 5CT oil casing pipe and mostly utilized for oil well with varied end connections such as non-Upset ends or an external upset end.

There is two types for API 5CT N80 oilfield casing pipes: N80-1 and N80-Q types, which have the same chemical composition and mechanical attributes while just various in the heat treatment. N801 steel pipe is treated by normalizing and tempering and N80Q is treated by quenching and tempering. The collapsing strength and internal pressure strength of N80Q are higher than that of N801 correspondingly.

API 5CT N80 Casing Tubing Color Code

Name Casing Coupling
N80-1 a bright red band entire red coupling
N80-Q a bright red band + a green band entire red coupling + a green band

API 5CT N80 Chemical Composition

Grade C Si Mn P S Cr Ni Cu Mo
N80 type1/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 1 552-758 689 0.5
N80 type Q 552-758 689 0.5

API 5CT N80 Tolerance

Item Allowable tolerance
Outer diameter Pipe body D≤101.60mm±0.79mm
Wall thickness -12.5%
Wight Single piece +6.5%+3.5%
Total weight -1.75

API 5CT N80 Size Chart

Outer Diameter Wall Thickness Weight Grade Threaded Length
in mm kg/m lb/ft
4 1/2″ 114.3 14.14-22.47 9.50-11.50 N80 LTC/STC/BTC R1/R2/R3
5″ 127 17.11-35.86 11.50-24.10 N80 LTC/STC/BTC R1/R2/R3
5 1/2″ 139.7 20.83-34.23 14.00-23.00 N80 LTC/STC/BTC R1/R2/R3
6 5/8″ 168.28 29.76-35.72 20.00-24.00 N80 LTC/STC/BTC R1/R2/R3
7″ 177.8 25.30-56.55 17.00-38.00 N80 LTC/STC/BTC R1/R2/R3
7 5/8″ 193.68 35.72-63.69 24.00-42.80 N80 LTC/STC/BTC R1/R2/R3
8 5/8″ 219.08 35.72-72.92 24.00-49.00 N80 LTC/STC/BTC R1/R2/R3
9 5/8″ 244.48 48.07-86.91 32.30-58.40 N80 LTC/STC/BTC R1/R2/R3
10 3/4″ 273.05 48.73-97.77 32.75-65.70 N80 LTC/STC/BTC R1/R2/R3
11 3/4″ 298.45 62.50-89.29 42.00-60.00 N80 LTC/STC/BTC R1/R2/R3
13 3/8″ 339.72 71.43-107.15 48.00-72.00 N80 LTC/STC/BTC R1/R2/R3

WLD steel is a leading manufacturer & supplier of API 5L Pipe for pipeline transportation systems in the petroleum and natural gas industries. We stock a full range of API 5L N80 PSL-1 & PSL-2 line pipe in seamless and welded processing. You can search for any size & grade steel pipe by our contact form.