ISO 18489:2015 is an ISO test method used to evaluate slow crack growth (SCG) resistance of polyethylene (PE) materials used in piping systems under cyclic loading, using a cracked round bar (CRB) specimen.
If you need help determining whether CRB testing is the right fit versus other SCG approaches (or which edition to cite), you can talk with our team about your material, product form, and qualification requirement.
ISO 18489:2015 — Polyethylene (PE) materials for piping systems — Determination of resistance to slow crack growth under cyclic loading — Cracked Round Bar test method
ISO 18489 describes an accelerated fracture-mechanics-style approach for comparing SCG performance of PE grades and PE piping-system products using cyclic loading at ambient temperature.
The method is used for PE materials, pipes, and fittings, including specimen sources such as compression moulded sheet, extruded pipe, and injection moulded fittings (when thickness and sampling allow appropriate CRB specimens).
Quick definition
ISO 18489 is a cyclic cracked round bar (CRB) test method for assessing resistance to slow crack growth in polyethylene piping materials at around 23 °C.
What This Standard Covers
ISO 18489 focuses on slow crack growth behavior under cyclic loading using a cracked round bar specimen geometry.
In practical terms, the standard guides how a prepared CRB specimen is cycled and how the result is used to characterize and compare SCG resistance for piping-oriented PE grades (commonly including PE 80 and PE 100) and related product forms (pipe and fittings) where SCG is a key long-term durability concern.
Why This Standard Matters in Testing
For pressurized PE piping systems, slow crack growth is a common long-term failure mechanism. ISO 18489 supports material development, grade comparison, and quality/qualification work where cyclic loading is used to accelerate crack-growth assessment while staying near typical ambient service temperatures.
This method is often considered when conventional long-duration SCG-type tests are too slow for development cycles, benchmarking, or timely release decisions.
Common Materials, Product Types, or Applications Covered
Common materials: Polyethylene (PE) pipe grades (often including PE 80 and PE 100), and PE formulations intended for piping durability.
Common product forms: PE pipes, PE fittings, and PE plaques/sheets used to machine test specimens.
Common applications: Water distribution, gas distribution, industrial piping, and other PE piping uses where long-term crack resistance is a critical performance driver.
Common Test or Verification Workflow
ISO 18489 is typically used as part of a material qualification or comparison workflow rather than a finished-product pressure test.
Typical workflow elements: selecting the specimen source (sheet/pipe/fitting), machining the cylindrical specimen, introducing a controlled notch/crack feature consistent with the CRB approach, running a controlled cyclic loading program at around 23 °C, and reporting the resulting SCG resistance metric(s) required by the citing program or specification.
Practical caution: Results are sensitive to specimen preparation quality and the exact loading and temperature conditions. For procurement or compliance, match the edition cited by your customer/specification and align lab setup and reporting to that citation.
Equipment Commonly Used for This Standard
ISO 18489 drives equipment selection primarily around controlled cyclic loading, stable alignment, and reliable measurement and control rather than a simple monotonic tensile setup.
Common equipment: A servo-hydraulic or electrodynamic fatigue-capable load frame sized for the required force range; appropriate fixtures/grips for round bar specimens; control and data acquisition suitable for cyclic programs; and temperature control appropriate for ambient (and any optional non-ambient work if used by a program).
Common supporting tools: Specimen machining and notch/crack preparation tooling suitable for repeatable CRB specimen production, plus measurement tools for verifying critical specimen dimensions and crack/notch features before/after testing.
How to Read This Designation or Revision
Standard designation: ISO 18489:2015.
What the year means: The “2015” indicates the publication year of the referenced edition. Some users may also encounter a corrected text release associated with this edition, so the safest approach is to cite the exact version/edition specified by your customer or governing document.
Revision sensitivity: Because ISO 18489 is under revision (with a draft revision in progress), test labs and buyers should confirm they are aligning equipment capability, control mode, and reporting to the exact cited edition.
Related Standards, Methods, or Frameworks
Slow-crack-growth and crack-resistance programs for PE piping may reference multiple complementary methods. Depending on your requirement, it can be helpful to review adjacent ISO methods used for SCG-related characterization, such as ISO 18488 (strain hardening modulus in relation to slow crack growth) and ISO 16770 (full-notch creep test for environmental stress cracking of PE).
Request equipment guidance for ISO 18489 testing
If you are specifying a fatigue-capable frame, fixtures, and controls for CRB-style cyclic testing, you can request a detailed quote with your force range, specimen size, and throughput targets.