ISO 19899:2010

Overview

ISO 19899:2010 specifies the Accelerated Relaxation and End Load (AREL) test method for mechanically jointed polyolefin pipe and mechanical fitting assemblies. The standard is intended primarily for assemblies with nominal outside diameter d ≤ 63 mm and assesses the effect of component relaxation and creep on the assembly’s resistance to pipe pull‑out under a long‑term, constant longitudinal force. The method also examines the susceptibility of pipes to stress crack failure initiated by the joint.

Key Topics

• Scope and principle: Assemblies are conditioned in water or air (normally 80 °C) and subjected to a constant longitudinal tensile force for a defined period to simulate the combined effects of internal pressure, thermal contraction and secondary bending.
• Test conditions: Typical test temperature is 80 °C (can be reduced for assemblies with non‑polyolefin components with test duration adjustments). The applied end load is maintained for a minimum of 500 hours.
• Apparatus requirements: Tensile loading equipment accurate to ±1% of indicated force; forced circulation and tight temperature control (±1 °C recommended) for reproducible results.
• Test piece geometry: Test assemblies use Type A end caps (ISO 1167‑1) with a free pipe length between fitting and cap of at least 100 mm or twice the pipe diameter (max 250 mm).
• Loading procedures and tolerances: Apply load gradually within (5 ± 1) minutes; force tolerances are ±2% for d ≤ 250 mm and ±5% for d > 250 mm.
• Leak testing: After conditioning to 23 ± 2 °C, assemblies are leak‑tested per ISO 3458 at 25 mbar and at 1.5 × nominal pressure; gas or water media selection follows safety and application rules.
• Annex A: Provides end‑load force tables for PE 80 and PE 100 pipes and a formula for calculating forces for other SDRs; the constant K varies with pipe diameter.

Applications

Who uses ISO 19899:2010 and why:

• Manufacturers of polyolefin pipes and mechanical fittings - for type testing, design validation and product development.
• Independent test laboratories and certification bodies - to verify long‑term joint performance against creep and relaxation‑related pull‑out.
• Utilities and system designers (gas and water) - to assess joint reliability and reduce risk of stress cracks or leakage.
• Quality assurance and R&D teams - to correlate product changes with long‑term mechanical behavior.

Practical uses include qualification of full end‑load‑bearing fittings for gas/water distribution, assessing joint durability in warm service conditions, and establishing performance baselines for regulatory compliance.

Related Standards

• ISO 1167‑1 / ISO 1167‑4 - preparation and methods for pressure resistance testing of thermoplastic pipes and assemblies.
• ISO 3458 - leakproofness testing of assembled joints.
• ISO 3 / ISO 497 referenced for preferred number series used in MRS sizing.

Keywords: ISO 19899:2010, AREL test, polyolefin pipes, mechanical fittings, end load test, PE 80, PE 100, creep, relaxation, leak test, SDR, tensile loading.