Aramco-RTFI Presentation 10-1-21

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Radiographic Film Interpretation of Welds ASNT Saudi Arabian Section Jim Carswell

RTFI Presentation Outline Morning 8:00am – 12:00noon • • • •

Interpretation/perception Welding processes Appearance and classification of defects Review acceptance criteria: ASME B31.1 API 1104 AWS D1.1 • Interpret radiographs

Afternoon 1:00pm – 4:00pm • Interpret radiographs

This presentation reviews the process of detecting, classifying and evaluating to acceptance criteria discernable defects on radiographic film.

Factors affecting Interpretation •Heredity/Genetics and visual perception • Can you see it? •What do you see? •Perception •Distortion •Illusion •Detection

Perception

Distortion

Illusion

Detection

How many faces can you detect?

There are eleven faces Scoring: 1-4 8 9 10 11

average extraordinary above average very observant extremely observant

Factors affecting Interpretation •

Heredity/Genetics and visual perception

• Condition of the human eye • •

Eye examinations 20/40 Wear your glasses/contacts, if scratched – replace.

Factors affecting Interpretation • • •

Heredity/Genetics and visual perception Condition of the human eye

Equipment • • •

Viewer/densitometer Viewing conditions Tools

Factors affecting Interpretation • • • •

Heredity/Genetics and visual perception Condition of the human eye Equipment Film and radiographic techniques • Discussing throughout

When in doubt Ask for 2nd opinion Re-shoot Grind & re-shoot

Radiography

Contact - DWSV

Elliptical - DWDV

Single wall single view

Radiographic film

Film processing

Results: good technique

Welding Joining materials at the atomic/molecular level

Welding equipment Welding is generated by an electric arc

Terminology

Five Basic Weld Joints

Common Welding Processes Used In The Petrochemical Industry • SMAW (Shielded Metal Arc Welding) • GMAW (Gas Metal Arc Welding) • GTAW (Gas Tungsten Arc Welding) • SAW (Submerged Arc Welding)

Shielded Metal Arc Welding (SMAW) Welding is generated by an electric arc established between the flux covered electrode and the base metal and melts the two together.

Benefits of the electrode coating •Arc stabilization •Provides gas shielding – decomposition of cellulose and limestone •De-oxidation of weld pool •Strengthens the weld - adds alloying elements •Increases deposition by adding iron filler •Slag provides oxide barrier for solidifying metal •Slag provides thermal insulation of the cooling weld

Common defects associated with SMAW Porosity Cracks Slag Incomplete fusion Incomplete penetration Burn through Lack of fill Root concavity Undercut Excessive penetration • The SMAW process is almost totally operator dependant

Gas Metal Arc Welding (GMAW) Welding is generated by an electric arc between a continuously fed solid wire consumable and the base metal

Common defects associated with GMAW Porosity Cracks Incomplete fusion Undercut lack of fill Incomplete penetration

•The GMAW process is automated, semi-automated and machine.

Gas Tungsten Arc Welding (GTAW) Welding is generated by an electric arc between a tungsten electrode, a solid wire consumable and the base metal.

Common defects associated with GTAW Porosity Tungsten inclusions Cracks Incomplete fusion Undercut •The GTAW process is almost totally operator dependant

Submerged Arc Welding (SAW) Welding is generated by an electric arc between a continuously fed solid wire consumable and the base metal while totally submerged in a protective flux.

Common defects associated with SAW Porosity Cracks Slag Incomplete fusion •The GMAW process is automated, semi-automated and machine.

Welding Defects

Common causes of defects •Welder-technique •Cleaning •Joint preparation •Joint design

Welding technique

Cleaning

(Porosity, Fusion, Tungsten & Slag)

Cleaning - slag removal

Joint preparation - poor fit-up (Fusion, Penetration & Mismatch - Hi-Lo)

POROSITY

Causes: •Contamination •Moisture •Environment – wind, etc.

Porosity

Porosity

Cluster Porosity

Cluster Porosity

Aligned Root-Pass Porosity

Hollow Bead

Incomplete Fusion

Causes: •Incomplete penetration of arc •Inadequate welding current •Poor joint fit-up

Incomplete fusion - Sidewall

Incomplete Penetration

Cause: •Poor joint design •Welding technique

Incomplete Penetration

Incomplete Penetration

Incomplete Penetration

Incomplete Penetration

Mismatch - Hi low

Cause: •Poor joint fit-up

Mismatch

Mismatch

Cracks

Causes: •Stress - thermal/mechanical •Welding technique •Electrode material (wrong alloy)

Transverse Cracks

Transverse Cracks

Longitudinal Root Crack

Longitudinal Root Crack

Slag Inclusion

Causes: •Non-removal •Welding technique

Interpass Slag

Interpass Slag

Burn Through

Cause: •Welding technique •Poor joint fit-up

Burn Through

Burn Through

Root Concavity

Cause: •Welding technique •Poor joint fit-up

Root Concavity

Root Concavity

Undercut

Cause: •Welding technique – excessive heat

Internal Undercut

Internal Undercut

External Undercut

External Undercut

Excessive Penetration

Cause: •Welding technique – excessive arc penetration •Poor joint fit-up

Excessive Penetration

Excessive Penetration

Lack of Fill

Cause: •Welding technique

Lack of Fill

Lack of Fill

Tungsten Inclusion

Cause: •Welding technique

Tungsten Inclusions

Tungsten Inclusions

Weld Spatter Cause: •Poor joint fit-up •Welding technique

Miscellaneous

Film Handling And Processing Defects Scratches Finger prints Crimp marks Light Leaks Chemical Stains Roller Marks & Artifacts

Scratches

Chemical Stains

Light Leaks

Static Marks

Store film upright

Artifacts

Water marks

Crimp marks

CODES & STANDARDS in the petrochemical industry

What is the purpose for Codes & Standards? They ensure uniform practices throughout industry

Three common codes used in Saudi Arabia’s petrochemical industry ASME B31.3 In-Plant Process Pipe API 1104 Welding of Pipelines And Related Facilities

AWS D1.1 Structural Welding Code - Steel

ASME B31.3 and Appendix 4 Film interpretation acceptance criteria for Process Piping “on-plot” facilities

API 1104 Film interpretation acceptance criteria for pipelines

AWS D1.1 Film interpretation acceptance criteria for structures

END