Overview
EN ISO 1167-4:2007 - "Thermoplastics pipes, fittings and assemblies for the conveyance of fluids - Determination of the resistance to internal pressure - Part 4: Preparation of assemblies" specifies how to prepare assemblies for hydrostatic pressure testing under ISO 1167-1. The standard covers the preparation of end‑load‑bearing and non‑end‑load‑bearing assemblies made from thermoplastic pipes, fittings, valves and joints (fusion or adhesive) so that their resistance to internal pressure can be assessed consistently and reproducibly.
Key Topics and Requirements
- Scope and principle
- Defines the procedure for assembling test pieces that will be conditioned and subjected to internal hydrostatic pressure testing according to ISO 1167-1.
- Sampling and timing
- Sampling is done as required by the relevant product standard; the interval between production and testing follows material or general specifications.
- Types of assemblies
- Fused assemblies: butt fusion, electrofusion, and multi-component “test tree” configurations; requirements for pipe ends, cleanliness and fusion per manufacturer/product standards.
- Mechanical end-load-bearing assemblies: assembled at ambient temperature unless specified, using manufacturer’s torque/assembly instructions, with torque measurement and no re‑tightening before leakage testing.
- Adhesively bonded assemblies: surface preparation and adhesive application per adhesive manufacturer; specified diametrical clearance, setting time and curing conditions (temperature and humidity).
- Preparation details
- Pipes and components must be cut square, free from impurities, clean, grease‑free and dry.
- Conditioning and bonding often specified at (23 ± 2) °C and (50 ± 5) % RH (when stated); removal of excess adhesive and storage in ventilated area during setting.
- Measurement and tolerance
- Procedures for measuring dimensions and, where necessary, simulating assembly tolerance variations (machining sockets, free pipe length requirements).
Applications and Who Uses It
- Manufacturers of thermoplastic pipes, fittings, and valves - for product development, quality control and type testing.
- Independent test laboratories - to prepare standardised test pieces for hydrostatic pressure testing.
- Certification bodies and regulators - to verify compliance with pressure resistance requirements.
- R&D and materials engineers - to evaluate joint methods (fusion, adhesive, mechanical) and long‑term performance under internal pressure.
- Specifiers and procurement - to ensure test evidence and consistent assembly preparation for acceptance testing.
Related Standards
This standard is essential when preparing test assemblies for reliable hydrostatic pressure testing of thermoplastic piping systems, ensuring consistent, repeatable results across manufacturers and test houses.