ISO 8513:2023 describes test methods used to determine initial longitudinal tensile strength and ultimate elongation for glass-reinforced thermosetting plastics (GRP) pipes.
If you need help aligning your specimen type (strip vs full pipe section) to the correct method and lab setup, talk with our team about your pipe construction, diameter, and reporting needs.
ISO 8513:2023 — Plastics piping systems — Glass-reinforced thermosetting plastics (GRP) pipes — Test methods for the determination of the initial longitudinal tensile strength
ISO 8513 is used in GRP pipe qualification and verification programs where longitudinal tensile performance must be demonstrated using a standardized approach. The standard provides alternative test methods intended for different pipe sizes and constructions, with results that are not necessarily interchangeable across methods.
Quick Definition
ISO 8513:2023 defines two tensile test methods for GRP pipes to determine longitudinal tensile strength and percentage ultimate elongation in the pipe’s longitudinal direction.
What This Standard Covers
This standard specifies two approaches for preparing and testing GRP pipe specimens in longitudinal tension:
Method A: Uses a longitudinal strip cut from the pipe.
Method B: Uses a specified length of the full pipe cross-section.
The outputs addressed are longitudinal tensile strength and percentage ultimate elongation. ISO 8513 does not address determination of longitudinal tensile modulus, and it points users to ISO 527-4 and ISO 527-5 when modulus is required.
Why This Standard Matters in Testing
GRP pipes are anisotropic and often multi-layered, so test setup and specimen selection can strongly affect measured results. ISO 8513 matters because it standardizes how a lab derives initial longitudinal tensile strength for pipe designs that may be circumferentially wound, helically wound, or centrifugally cast.
Because different ISO 8513 methods can produce different results, it is important to keep the method consistent within a qualification program and to clearly state the method in test reports and procurement requirements.
Common Materials, Product Types, or Applications Covered
ISO 8513 applies to glass-reinforced thermosetting plastics (GRP) pipes used in plastics piping systems. Method applicability depends on pipe type and nominal size, and the standard describes typical use cases for each method (for example, strip testing for certain larger nominal sizes and full-section testing commonly used for smaller nominal sizes).
Common Test or Verification Workflow
ISO 8513 is typically used as part of a pipe product verification workflow where a manufacturer or test lab must demonstrate longitudinal tensile performance on representative pipe samples.
Common workflow: select method (A or B) based on pipe construction and nominal size, prepare the specimen form required by the chosen method, load the specimen in tension until failure, and report longitudinal tensile strength and ultimate elongation while documenting the method used.
Equipment Commonly Used for This Standard
ISO 8513 is performed on tensile testing equipment configured for the specimen geometry created by Method A or Method B.
Common equipment: a universal testing machine (UTM) with appropriate force capacity, suitable grips/fixtures for either a longitudinal strip specimen (Method A) or a full pipe-section arrangement (Method B), and instrumentation to capture load and elongation to the level required for reporting ultimate elongation.
Because this standard focuses on strength and ultimate elongation (and not modulus), the strain/elongation measurement approach is typically selected to match the required output and the specimen/fixture constraints rather than to support high-precision modulus determination.
If you are selecting a UTM capacity and fixtures for GRP pipe tensile testing, you can request a detailed quote for a configuration matched to your specimen type and expected failure loads.
How to Read This Designation or Revision
ISO 8513:2023 indicates the ISO standard number (8513) and the publication year (2023). ISO 8513 has multiple historical editions; test setups and method details can vary by edition, so purchase specifications and test reports should cite the full designation including year.
Current edition status: ISO 8513:2023 is published, and earlier editions such as ISO 8513:2016 are withdrawn.
Related Standards, Methods, or Frameworks when useful
When longitudinal tensile modulus is required for GRP materials, ISO 8513 points users toward ISO 527-4 and ISO 527-5 as relevant references for modulus determination. In practice, labs may use ISO 8513 for strength/ultimate elongation on pipe-derived specimens while using ISO 527-series methods for modulus on appropriate composite specimens when feasible.
Talk to a testing specialist
If your customer specification cites ISO 8513 and you need help mapping it to the right method, fixtures, and machine capacity, contact our team with the pipe DN, construction (e.g., circumferential/helical/centrifugal), and the edition year you are required to follow.