Overview
ISO 9311-2:2011 - Adhesives for thermoplastic piping systems - Part 2: Determination of shear strength - specifies a laboratory test method to measure the shear strength of adhesive-bonded joints used in thermoplastic piping systems. The standard defines the specimen preparation, conditioning, test apparatus and procedure, calculation of shear strength and the required test report content. It is intended for characterizing adhesives under controlled conditions; results are not directly extrapolable to every in-service joint.
Key topics and requirements
- Scope and intent: Method to determine shear strength of joints bonded with adhesives for thermoplastic piping systems (ISO 9311-2:2011).
- Sampling and preparation: Follow ISO 15605 for sampling and EN 1067 for sample preparation; use manufacturer surface-preparation recommendations.
- Test specimens: Typical assemblies use a pipe length of 75 mm, external diameter 40 mm and a fitting with at least 20 mm joint contact depth. Diametrical clearance is specified per referenced product standards.
- Conditioning: Condition test pieces at (23 ± 2) °C and (50 ± 5) % RH for at least 6 hours; maintain curing under the same conditions and vertical position.
- Apparatus and loading: Use a tensile or press testing machine with a jaw movement rate of (5 ± 0.5) mm/min and an appropriate jig to connect the assembly.
- Failure and area reduction: Record maximum force at failure. If the required force exceeds machine capacity, reduce bonded area by cutting a 10 mm ring from the bond (per standard).
- Calculation: Shear strength (MPa) is calculated from the failure force divided by the bonded area (F / (π · d · l)) where d = internal fitting diameter and l = joint length.
- Test series and reporting: Test five assemblies and report individual results and arithmetic mean. Test report must reference ISO 9311-2:2011 and include adhesive ID, specimen prep, diametrical clearance, curing and test temperatures, joint dimensions, and any deviations.
Applications and users
ISO 9311-2:2011 is used for:
- Quality control and batch verification by adhesive manufacturers.
- Product development and comparative testing in R&D labs.
- Compliance testing for pipe and fitting manufacturers and certification bodies.
- Material selection and specification by engineers and consultants designing thermoplastic piping systems.
Practical applications include performance benchmarking, validation of bonding procedures, and supporting product specifications for pressure and non-pressure thermoplastic piping systems.
Related standards
- ISO 9311-1: Determination of film properties
- ISO 9311-3: Test method for resistance to internal pressure
- ISO 15605 (sampling), EN 1067 (sample prep), EN 923 (terms)
- EN 14680 and EN 14814 (product specifications referencing this test method)
Keywords: ISO 9311-2:2011, shear strength, adhesives for thermoplastic piping systems, bonded joint testing, test method, diametrical clearance, curing conditions.