01AL₂O₃
Caustic cracking
Alumina refining
Welds and heat-affected zones exposed to concentrated caustic liquor, elevated temperature and residual fabrication stress.
Request an inspectionSpecialist ultrasonic inspection · Australia-wide
Stress corrosion cracking is silent until it breaks the external surface.
Australia-wide specialist inspection for early-stage cracking in welds and pressure equipment—before a fine, branching flaw becomes an integrity event.
- PAUT
- Encoded crack detection
- TFM / FMC
- High-resolution imaging
- TOFD
- Through-wall sizing
MACROSCOPIC SURFACE EVIDENCEPIPE SECTION
MICROSTRUCTURE CORRELATIONSEM / 20 μm
Detect · Characterise · Size · Report
Available Australia-wide · Call 1300 004 647
01 / Failure mechanism
Three conditions. One highly specific failure mode.
SCC develops when a susceptible material, tensile stress and a specific corrosive environment intersect. The component can look sound while a crack network grows beneath the surface.
01Susceptible
material
material
02Tensile
stress
stress
03Specific
environment
environment
SCCinitiation zone
It is not general corrosion.
Uniform wall loss is usually visible or measurable with a thickness survey. SCC is localised, crack-like and mechanism-dependent. Fine branches can initiate at pits, weld toes or heat-affected zones and propagate with little obvious surface evidence.
- 01Define the material–environment pairing
- 02Map weld geometry and likely stress concentration
- 03Select beam paths for crack orientation
- 04Record data for sizing and future comparison
Australia-wide inspection supportNeed certainty on a suspected SCC mechanism?
02 / Industry-specific risk
The environment determines what—and where—we look.
There is no generic “SCC scan.” Inspection is scoped around the alloy, chemistry, temperature, fabrication history and stress state of the asset.
02NH₃
Ammonia SCC
Ammonia systems
Carbon-steel storage vessels, spheres and process welds where oxygen, water and tensile stress can drive cracking.
03Cl⁻
Chloride SCC
Chloride service
Austenitic stainless piping, vessels and insulated equipment exposed to chlorides and temperature.
04RNH₂
Amine SCC
Amine processing
Carbon-steel absorber, regenerator and piping welds subject to local hard zones and residual stress.
05CO₃²⁻
Carbonate SCC
Carbonate systems
FCC gas plants, syngas and sour-water systems where carbonate chemistry and tensile stress intersect.
06H₂S
Environmental cracking
Sour service
Welds and pressure equipment requiring a mechanism-specific plan for wet-H₂S damage and crack-like indications.
Australia-wide inspection supportNeed certainty on a suspected SCC mechanism?
03 / Inspection strategy
Build the examination around the crack—not the instrument.
We combine complementary ultrasonic datasets where geometry and access allow, then report what was covered, what was found and what the indication means.
PAUT
Locate and characterise
Multiple beam angles interrogate the weld volume and likely crack planes from a controlled scan position.
- Output
- S-scan / encoded data
- Value
- Coverage and orientation
TFM / FMC
Resolve complex indications
Full matrix data can be reconstructed with selected wave modes to improve imaging around difficult crack morphology.
- Output
- High-resolution image
- Value
- Characterisation confidence
TOFD
Support through-wall sizing
Diffracted signals from crack tips can support depth measurement when the flaw, geometry and access suit the technique.
- Output
- B-scan / tip response
- Value
- Depth and monitoring baseline
Method selection is procedure-led. Final techniques, coverage and acceptance criteria are confirmed against the asset, material, geometry and applicable inspection requirements.
Australia-wide inspection supportNeed certainty on a suspected SCC mechanism?
04 / Evidence chain
From field indication to defensible finding.
The output is built for the asset engineer: traceable locations, retained datasets, indication characterisation and clear next actions.
Crack morphology and position inform the ultrasonic examination plan.
Australia-wide inspection supportNeed certainty on a suspected SCC mechanism?
05 / Documented cases
What SCC looks like—from plant scale to grain scale.
Real failure evidence is more useful than generic industrial photography. These examples connect the visible component, weld location, fracture surface and microscopic crack path.
Australia-wide inspection supportNeed certainty on a suspected SCC mechanism?
06 / Project sequence
A focused path from risk hypothesis to inspection record.
- 01
Define the mechanism
Confirm asset, material, chemistry, temperature, fabrication and operating history.
- 02
Engineer the scan
Select access, probe configuration, calibration blocks and coverage strategy.
- 03
Acquire encoded data
Scan controlled locations and retain interpretable datasets for review.
- 04
Characterise and size
Correlate responses, crack orientation, morphology and through-wall extent.
- 05
Report for action
Deliver traceable findings and practical recommendations for engineering review.
Australia-wide inspection supportNeed certainty on a suspected SCC mechanism?
Technical basis
Inspection requirements, translated into usable evidence.
Project procedures and reporting can be scoped with reference to the relevant asset code and examination standard, including:
AS 3788API RP 571ASME Section VISO 17640ISO 10863ISO 13588
Applicable editions, acceptance criteria and personnel requirements are confirmed during project scoping.
Australia-wide inspection supportNeed certainty on a suspected SCC mechanism?
Australia-wide inspection support
Tell us where the risk is.
Share the asset, material, service environment and timing. We’ll review the likely mechanism and come back with the next practical step.
Call our inspection team1300 004 647 ↗Direct emailinfo@sccinspections.com ↗Inspection services delivered by IMIS Asset Integrity Pty Ltd