REF: 4.5.2 Anomaly Assessment Procedure R6
Pipeline Integrity Reference
Anomaly naming conventions, marker color coding, and field measurement requirements for Trans Mountain pipeline inspections.
- Contact Technical Services to establish grind length and depth limits prior to grinding to depths greater than 10% of NWT.
- Contact Technical Services for direction before performing any buffing within HAZ (25mm) of any weld.
- Girth welds will be examined only when the dig is targeting Girth weld anomalies.
Naming Convention
Anomalies are identified by a prefix followed by a sequential three-digit number. All positional measurements are center-to-center.
DNTM-001
Prefix + Sequential Number
Anomaly Prefix Legend
| INT | Interacting cluster of metal loss features |
| ML | Metal loss feature (including body inclusion or metal loss due to grinding) |
| LI | Linear indication |
| INLI | Interacting linear indications |
| COL | Colony of Linear Indications |
| LAM | Lamination |
| GWM | Girth Weld defects |
| SW | Long Seam weld defects |
| ARC | Arc Burns |
| WFI | Weld Fill Ins |
| DNTM | Dent — Manual |
| GOUM | Gouge — Manual |
| WRM | Ripple or buckle |
| OTH | Other features (including manufacturing defects) |
Marker Color Coding
Green
ILI Feature Boundary / Box — All Features: Square box
Red
Crack Like Indications — SCC Colony Boundaries — MFG/Weld Anomalies
Blue
Geometric Indications — Dents, Gouges, Mechanical Damage, Wrinkles
Purple
Laser Scan Mark up
Black
Metal Loss/Grinds and Arc Burns/Weld Fill-in Damage — All other pipe markings
ARC Arc Burns
Documentation requirements for arc burn anomalies found during pipeline inspection.
Info Badge Template
| Field ID | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Within HAZ | HV As Found | LI Present | HV After Buff | LI Post-Buff | Circumf. Dir. | Overlap | Assoc. ML |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ARC-001 | T | ||||||||||||
| ARC-002 | T |
Important Notes
- Hardness Vickers over 350 HV considered a defect
- Surface prep Arc Burn to get accurate As Found HV readings
- Perform 0 degree UT / Shearwave or PAUT in area of Arc Burn
- Over >10% NWT wall loss shall be documented as Metal Loss
- Acid Etch or Nital (5%) to be performed and photographed at intervals (10% NWT, then every 1mm).
- Record Hardness of unaffected and affected material
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
Example of Arc Burn markup
Field Example
Example of Metal Loss markup after arc burn removal
LAM Lamination Indications
Documentation for lamination and inclusion anomalies detected via UT inspection methods.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Dist. to Weld Lw | Length S (mm) | Width C (mm) | Bulge B (mm) | Height Lh (mm) | Cracks | Overlap |
|---|---|---|---|---|---|---|---|---|---|---|---|
| LAM-001 | T | ||||||||||
| LAM-002 | T |
Important Notes
- Perform UT sizing 50mm around indication for accurate sizing
- Perform UT Shearwave or PAUT to determine if cracking/bulging is present
- Interaction criteria is 2T NWT or less (Ls < 2T)
- Stingers/Inclusions where S < 10mm and C < 6mm are not considered relevant when in-service welding is involved
- Non-sloping, non-cracking, non-overlapping lams where S > 30mm and C 10mm will be documented; anything smaller do not enter in 24H NDE Report
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Measurement Definitions
STotal longitudinal length of the lamination or inclusion
CTotal circumferential length of the lamination or inclusion
BMaximum height above pipe wall surface of any bulges
LhVertical extent of any sloping (max depth minus min depth)
LSMinimum distance between adjacent laminations or inclusions
LWMinimum distance between the defect and closest weld
tmmMinimum thickness between the lamination and closest pipe wall surface
Field Example
TMPL Line 1 · Hinton–Blue River · NPS 24 · 1KP455.031 Dig T15136960 — OTH-001 & ML-012 badges documented on pipe steel
DNTM Dents
Manual dent assessment documentation. Document both Laser scan (Purple) and Manual assessment (Blue) measurements on pipe.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Max Depth (mm) | Other Features | Under Coating | Indenter Type |
|---|---|---|---|---|---|---|---|---|---|---|
| DNTM-001 | T | |||||||||
| DNTM-002 | T |
Important Notes
- Perform UT Shearwave / PAUT in dent area to inspect for mid/internal reflectors
- Document Laser scan measurements (Purple) and Manual assessment measurements (Blue) on pipe
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
Example of dent markup
LI Linear Indications
Documentation for linear indications detected through UT and PAUT inspection methods.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Cont. Length (mm) | Depth (mm) | Height (mm) | Wall Surface | Circumf. Dir. | Removed by Buff |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| LI-001 | T | |||||||||||
| LI-002 | T |
Important Notes
- For details see Section 7.3.10 on the Anomaly Assessment Procedure (4.3.2) — See this section for ILI sizing
- Perform UT SWUT/PAUT to obtain depth/height of indication
- Depth of indication is from outer wall to bottom
- Height of indication is from top to bottom of reflection
- See Buffing Tab for proper stages of documentation
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
Example of linear indication markup
COL Stress Corrosion Cracking (SCC)
Colony-level SCC documentation with A-M-I (Average, Max, Interlink) classification system.
Info Badge Template
| Field ID | Assoc. ML | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Avg. Length | Max. Length | Interlink Length | Interacting With | Angle (°) | Removed by Buff |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| COL-001 | T | |||||||||||
| COL-002 | T |
Important Notes
- See 24H NDE Report for TM Interaction Calculator in SCC Tab
- Perform UT SWUT/PAUT to size indication
- Depth of indication is from outer wall to bottom
- Max length is the longest isolated indication
- A-M-I is for a colony of SCC/LI indications (Average, Max, Interlink)
- See Buffing Tab for proper stages of documentation
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
ML Buffing Features
Buffing profile procedure for crack removal with progressive depth documentation intervals.
Info Badge Template — Progressive Removal Profile
Buffing Depth Intervals
10%
7.128mm
RWT
RWT
1mm
6.92mm
RWT
RWT
2mm
5.92mm
RWT
RWT
3mm
4.92mm
RWT
RWT
40%
4.752mm RWT
Contact Tech Services
60%
3.168mm RWT
Approval Required
FIN
Final
Buff
Buff
Buffing Feature Information
| Field ID | Feature Buffed | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Depth (mm) |
|---|---|---|---|---|---|---|---|
| ML-001 | T | ||||||
| ML-002 | T |
Buffing Profile Procedure (Cracks)
| Field ID | L @ 10% | L @ 1mm (13%) | L @ 2mm (25%) | L @ 3mm (38%) | L @ 40% | L @ 60% | L Final | D Final | Fully Removed |
|---|---|---|---|---|---|---|---|---|---|
| ML-001 | |||||||||
| ML-002 |
Important Notes
- If buffing procedure reaches 40% NWT contact Tech Services for further direction
- MUST have Tech Services approval to buff past 60% NWT
- All wall loss calculations based off NWT
- Photograph each removal interval (10%, 1mm, 2mm, 3mm, 40%)
- Input final buff measurements (L-W-MD) into 24H report to determine whether area fails and needs a KAPA grid
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
TMPL Line 1 · Hinton–Blue River · NPS 24 · 1KP455.031 Dig T15136960 — OTH-001 & ML-012 badges documented on pipe steel
GOUM Gouge Indications
Manual gouge assessment documentation.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Max Depth (mm) | HV | Other Features | Fully Removed | Assoc. ML |
|---|---|---|---|---|---|---|---|---|---|---|---|
| GOUM-001 | T | ||||||||||
| GOUM-002 | T |
Important Notes
- UT Penprobe or Pitgauge for depth
- Perform 0 degree UT / Shearwave or PAUT in area of Gouge
- Surface prep to get accurate As Found HV readings
- Post removal HV MUST be added to Metal Loss Badge
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
Example of a gouge markup
Field Example
Example of gouge markup after grinding
SW / GWM Welding Indications
Documentation for seam weld and girth weld defects. For GWD, circumferential measurement is considered the length.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Weld Type | Axial +/- (m) | Circumf. (mm) | Width (mm) | Length (mm) | Cont. Length | H/D (mm) | Dist. to OD | Radial Loc. | Removed | Defect Type |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| LI-001 | T | ||||||||||||
| LI-002 | T |
Important Notes
- For details see Section 7.3.10 on the Anomaly Assessment Procedure (4.3.2) — See this section for ILI sizing
- Weld Type: S = Seam Weld, G = Girth Weld
- Defect Types (as per 24H NDE Report):
Incomplete Fusion
Incomplete Penetration
Crack
Slag Inclusion
Arc Burn
Weld Fill In
Porosity
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
Example of long seam indication markup
WRM Ripples, Buckles, Wrinkles
Deformation anomaly documentation. Use 24H report for h/D Ratio calculation.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Peak-to-Peak l (mm) | Max Depth h (mm) | h/D % | Other Features |
|---|---|---|---|---|---|---|---|---|---|
| WRM-001 | T | ||||||||
| WRM-002 | T |
Important Notes
- Perform UT Shearwave / PAUT in deformation area to inspect for mid/internal reflectors
- Document Laser scan measurements (Purple) and Manual assessment measurements (Blue) on pipe
- Enter Peak-to-Peak and Max. Peak-to-Valley Depth in 24H NDE report for h/D Ratio
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
Example of wrinkle mark up
WFI Weld Fill-Ins
Documentation for weld fill-in anomalies requiring underlying indication assessment.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Underlying Ind. | LI Present | LI Circumf. Dir. |
|---|---|---|---|---|---|---|---|---|---|
| WFI-001 | T | ||||||||
| WFI-002 | T |
Important Notes
- Perform UT 0 degree SWUT/PAUT to determine if there are underlying indications
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
ML / INT Metal Loss & Corrosion Indications
Documentation for metal loss, corrosion, and interacting cluster features.
Info Badge Template
| Field ID | ILI Call | Ref. GWD | Axial +/- (m) | Circumf. (mm) | Length (mm) | Width (mm) | Max Depth (mm) | MRWT (mm) | Type | Wall Surface | Seam Weld | Overlap |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ML-001 | T | |||||||||||
| ML-002 | T |
Important Notes
- 6T interaction rules apply for NWT of >10% loss. Corrosion less than 10% NWT is ignored.
- Document Max. depth or MRWT — not both
- Type: B = Buff, C = Corrosion, O = Other
- Use 24H NDE Report for Length to Depth ratio; will determine if Corrosion fails
- If Laser scan is performed, complete 5 verification points in the deepest areas. Laser and manual UT have to be within 5% NWT.
- Refer to 4.5.2 Anomaly Assessment Procedure R6 and 24H NDE Report form
Field Example
Marking up of laser verified corrosion feature
Interaction Rules
