API 5CT Casing pipe ,American Petroleum Institute API Specification 5CT/ ISO 11960:2001

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API 5CT Casing pipe ,American Petroleum Institute API Specification 5CT/ ISO 11960:2001

API 5CT Casing Pipe in Grade J55/K55, N80

API 5CT Casing Pipes

Table C.61—Summary of NDE methods for seamless and the body of welded pipe

Grade

Visual

inspection

(see 10.14)

Wall

thickness

determination

Ultrasonic

inspection

Flux leakage inspectionEddy current inspectionMagnetic particle inspection a
1234567
H40, J55 K55, N80 Type 1RNNNN’N
N80Q, L80 C95, M65RRAAAA
P110RRAAANA
C90, T95, Q125RRCBBB

N = not required R = required

A = one method or any combination of methods shall be used

B = at least one method shall be used in addition to ultrasonic inspection to inspect the outside surface C = ultrasonic inspection shall be used to inspect the outside and inside surfaces NA = not applicable

a MPI is permitted for end-area inspection. MPI is permitted for pipe body outside-surface inspection in combination with other methods of pipe body inspection. ‘

Table C.62—Acceptance (inspection) levels

GradeExternal imperfectionInternal imperfection
LongitudinalTransverseLongitudinalTransverse
12345
N80Q, M65, L80, C95L4L4
P110to A.9 (SR16)L4L4L4L4
P110L2L2L2L2
P110 to A.9 (SR16) and A.2 (SR2)L2L2L2L2
C90UTL2L2L2L2
T95-Q1252nd methodL2L2
Weld seam
P110, Q125L2NL2N
All other gradesL3NL3N
N = not required; Lx = acceptance (inspection) level.

Table C.63一Artificial reference indicators

AcceptanceNotch depth aNotch lengthWidthRadially drilled hole
(inspection) level max. at full depth diameterb
max.max. 
 %mmmmmm
12345
L255011,6
L3105013,2
L412,55013,2

a Depth as a percent of specified wall thickness. The depth tolerance shall be 士 15 % of the calculated notch depth with a minimum

notch depth of 0,3 mm ± 0,05 mm.

b Drilled hole diameter (through the pipe wall) shall be based on the drill bit size.

 

Table C.64—Size of stamp markings

ProductLabel 1Marking height
  mm
Pipe<4-1/24,8
 >4-1/26,4
CouplingPipe sizes < 4-1/26,4
 Pipe sizes > 4-1/2 to < 7-5/89,5
 Pipe sizes > 7-5/812,7

 

Table C.65一Grade colour codes

GradeNumber and colour of bands for pipe and pup-joints & 1,8 mColour(s) for coupling
 Tvpe Entire couplingBandfs)
12345
H40 None or black band at the manufacturer’s ootionNoneSame as for oiDe

J55

tubing

 One bright greenBright greenNone

J55

casing

 One bright greenBright greenOne white
K55 Two briqht areenBriaht areenNone
M65 One bright qreen, one blueM65 pipe uses L80 Type 1 couplings
N801One redRedNone
N80QOne red, one briqht qreenRedGreen
L801One red, one brownRedOne brown
L809CrOne red, one brown, two vellowRedTwo vellow
L8013CrOne red, one brown, one vellowRedOne vellow
C901One purplePurpleNone
C902One purple, one vellowPurpleOne vellow
T951One silverSilverNone
T952One silver, one vellowSilverOne vellow
C95 One brownBrownNone
P110 One whiteWhiteNone
Q1251One oranqeOranqeNone
Q1252One oranqe, one vellowOranqeOne vellow
Q1253One oranae, one areenOranaeOne areen
Q1254One oranae, one brownOranqeOne brown

Table C.66—Thread type markings

ProductThread typeMarked symbol
CasingShort roundSTC
 Long roundLC
 ButtressBC
 Extreme-lineXC
TubingNon-upsetNU
 External upsetEU
 Integral jointIJ

3 Comments

  1. neo- says:

    Schedule 80 pipe comparied to 40?

    • admin says:

      A previous description of pipe wall thicknesses as “Standard”, “Extra Strong” and “Double Extra Strong” has been supplanted by a schedule of 10, 20, 30, 40 60, 80, 100, 120 and 160. Schedule 40 pipe generally compares with the previous use of “Standard”. For metal pipe, Schedule 80 pipe has a thicker wall and can withstand greater pressures than a Sch 40 pipe. A point of confusion is that for PVC piping, Schedule 80 pipe has a thinner wall than Sch 40 pipe.

    • admin says:

      Thicker pipe wall is required to contain higher fluid pressures. For the same fluid pressure, a thicker pipe wall is required for a larger diameter pipe than that required for a pipe of smaller diameter. A schedule of pipe sizes and wall thicknesses has been established by ASTM standards governing manufacturing of pipe.

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