Lesson 10.02.03 - In-Line Inspection Tools (ILI Tools)

Question 1

What are ILI tools?

Answer 1

In-Line Inspection Tools

Question 2

What do ILI tools do?

Answer 2

ILI tools utilize various NDE methods to assess the in-service condition of the pipe.

Question 3

Why are ILI tools an essential and significant evaluation technique?

Answer 3

ILI tools provide the pipeline operator with real time data on the condition of their line and helps to ensure the correct maintenance decisions are made for the safe and cost-effective operation of the pipeline.

Question 4

What can be measured by ILI tools?

Answer 4

They can measure irregularities in pipe wall, corrosion, cracking, laminations, seam weld anomalies, and pipeline deformations.

Question 5

ILI tools are inserted into the pipeline at ___ or ___ stations with a configuration of pipes and valves known as a receiver.

Answer 5

valve, pump

Question 6

How are ILI tools set up for an inspection?

Answer 6

1. Tool is loaded into the receiver.
2. Receiver is closed and sealed.
3. Flow of product launches ILI tool into pipeline.

Question 7

What is the process during and after an ILI tool retrieval?

Answer 7

1. Tool is directed out of the pipeline into a receiver.
2. Tool is removed.
3. Recorded data is retrieved and used for analysis and reporting.

Question 8

When selecting the most suitable ILI tools for inspections, pipeline operators must know?

Answer 8

• Pipeline attributes
• Pipeline Geometry
• Pipeline Anomalies
• Threat Types and Risks the Pipe May Be Subject to
• Risk to property, personnel, and public presented by the pipe section being measured

Question 9

ILI tools were first introduced in the __.

Answer 9

1960s

Question 10

ILI tools typically employ NDE Techniques such as?

Answer 10

• MFL
• UTCW (Compression Waves)
• UTSW (Shear Waves)
• Caliper or Geometry Tools

Question 11

What are MFL ILI tools used for and how do they work?

Answer 11

They detect corrosion, gouges, mechanical damage, etc. through the use of Magnetic Flux Leakage.

Question 12

When using an MFL ILI tool, what causes an anomaly to appear?

Answer 12

A break in the magnetic flux of the pipe.

Question 13

What are UTCW ILI tools used for?

Answer 13

To detect metal loss anomalies, lamination, and measure wall thickness.

Question 14

What are UTSW ILI tools used for?

Answer 14

To detect linear crack-like anomalies.

Question 15

What is the most commonly used ILI technology?

Answer 15

MFL ILI Technology

Question 16

When does Axial MFL occur?

Answer 16

Axial MFL occurs when a strong magnetic flux is composed along the longitudinal axis of the pipe by on-board magnets oriented along that axis of the pipe.

Question 17

Apart from Axial MFL, what other type of MFL technology is available?

Answer 17

Circumferential or Transverse MFL (TFI)

Question 18

What does the Circumferential MFL Technology do/detect?

Answer 18

• Detects and classifies seam weld features as crack-like or not.
• Provides SCC and Corrosion depth sizing to +/- 15% NWT
• Detects and discriminates dents or dents with corrosion and cracking

Question 19

TFI utilizes a magnetic field oriented ___ and is wrapped completely around the pipe.

Answer 19

circumferentially

Question 20

The TFI tool is used to determine the location and extent of corrosion oriented ___ along the pipe, making TFI useful for detecting corrosion.

Answer 20

axially, seam-related

Question 21

What type of axial indications can a TFI tool detect that are undetectable with conventional MFL or UT tools?

Answer 21

• Axial Cracks
• Seam Weld Lack of Fusion (SW LOF)
• Stress Corrosion Cracking (SCC)

Question 22

What are the advantages of UT ILI tools?

Answer 22

• detect linear wall thickness measurements
• reliable defect depth sizing and good repeatability

Question 23

What flaws do UT ILI tools detect?

Answer 23

• internal and external metal loss
• longitudinal channeling
• blisters and inclusions
• deformations
• laminations
• cracking
• seam weld characteristics
• wall thickness variations

Question 24

What are the 2 UT tools commonly used for inspections of pipelines?

Answer 24

• Compression Wave UT Tools
• Shear Wave UT ILI tools

Question 25

What can UTCW tools do?

Answer 25

- Can easily determine and measure pipe wall thickness and metal loss

Question 26

How are UTCW tools used?

Answer 26

- Transducers are mounted perpendicular to the surface of the pipe. - Acoustic echoes are received from both the internal and external surfaces of the pipe.

Question 27

What is a shear wave?

Answer 27

A shear wave occurs when the vibratory energy is propagated by particle motion perpendicular to the direction of wave travel.

Question 28

What does EMAT stand for?

Answer 28

Electromagnetic Acoustic Transducer

Question 29

The EMAT tool consists of ___.

Answer 29

a coil in a magnetic field at the internal surface of the pipe wall.

Question 30

In the EMAT tool, an ___ applied to the coil induces an AC in the pipe wall causing ___ forces

Answer 30

alternating current (AC), Lorentz

Question 31

What are the advantages of EMAT ILI inspection?

Answer 31

- Dry coupling - Applicable to NG pipelines - Dry coupling increases reliability

Question 32

What are the disadvantages of EMAT ILI inspection?

Answer 32

- EMAT transducers need to be located about 1.0mm from the test object surface - Transmitted acoustic energy is low and the dynamic range is determined by noise - Low frequencies limit sensitivity

Question 33

What flaws do EMAT ILI tools detect?

Answer 33

- Internal and external metal loss - Longitudinal channeling - Hydrogen induced blisters and inclusions - Deformations - Laminations (sloping and stacked) - Toe cracking - Stress Corrosion Cracking (SCC) - Weld flaws

Question 34

What are Geometry or Caliper ILI tools also known as?

Answer 34

Caliper Pigs

Question 35

What do Geometry ILI tools do?

Answer 35

They measure the internal bore of the pipe through mechanical or electromagnetic methods.

Question 36

What anomaly data should Geometry ILI tools provide?

Answer 36

- Orientation - Location - Depth Measurment

Question 37

What does repair criteria depend on (when discussing Geometry ILI tools)?

Answer 37

Depth and orientation of dents.

Question 38

This type of tool can be used in both ___ ___ and ___ ___ pipelines

Answer 38

hazardous liquid, natural gas

Question 39

What applications are Geometry ILI tools used for?

Answer 39

- Dent detection - Out of round and bend - Bore monitoring - Mechanical or third-party damage detection - Pipeline restriction inspection prior to running more sophisticated (and expensive) tools.