Overview
EN ISO 1167-2:2006 specifies the dimensions and methods for preparing tubular test pieces used to determine the resistance of thermoplastics pipes to internal hydrostatic pressure (see ISO 1167-1 for the general method). The part covers both extruded and injection-moulded tubular specimens and sets measurement and reporting expectations to ensure repeatable, comparable hydrostatic testing.
Key Topics
- Scope: Preparation of extruded or injection-moulded tubular test pieces for hydrostatic pressure testing of thermoplastic pipes.
- Principle: Test pieces may be obtained by extrusion or injection moulding. Extruded test pieces are used for material and pipe testing; injection-moulded tubular test pieces are intended for testing injection-moulding materials.
- Dimensional requirements:
- Free length for extruded pieces: at least three times the nominal outside diameter (3 × dn), with a minimum of 250 mm. For pipes with dn > 315 mm a reduced free length of at least 2 × dn may be used where necessary.
- Injection-moulded tubular test pieces: nominal outside diameter between 25 mm and 110 mm inclusive. Free length normally 3 × dn; for smaller test pieces (≤ 50 mm nominal outside diameter) a minimum free length of 140 mm applies.
- Apparatus and measurement:
- End caps and assembly as referenced in ISO 1167-1.
- Wall thickness and mean outside diameter measurements to conform to ISO 3126 (e.g., Pi-tape for diameter). The rounding up procedure of ISO 3126 shall not be applied when these measurements are used for pressure calculations.
- Reporting: Test reports shall include the method of manufacture (extrusion or injection moulding) and the information required by ISO 1167-1.
Applications
- Establishing material performance and time-dependent behaviour of thermoplastic pipe materials under internal hydrostatic stress.
- Supporting classification and design strength determination when combined with extrapolation methods (e.g., ISO 9080) to derive long-term properties such as MRS and material classification in accordance with ISO 12162.
- Verifying material points on established stress/time regression curves and confirming the behaviour of compounds intended for fittings or pipe manufacture.
Related Standards
- ISO 1167-1:2006 - General method for determination of resistance to internal pressure.
- ISO 3126 - Measurement of dimensions for plastics piping components.
- ISO 9080 - Long-term hydrostatic strength determination by extrapolation.
- ISO 12162 - Classification and designation of thermoplastic materials for pressure applications.
This part of ISO 1167 defines practical specimen preparation and measurement rules that improve the reliability and comparability of hydrostatic pressure tests on thermoplastic piping materials and components.
