ISO 15306:2003

Overview

ISO 15306:2003 defines a laboratory method to determine the resistance of glass‑reinforced thermosetting plastics (GRP) pipes to cyclic internal pressure. Although the text refers to pipes, the procedure can also be applied to fittings. The standard sets out the test principle, required apparatus, test-piece preparation, test procedure, result expression and reporting requirements relevant to durability and fatigue assessment of GRP pressure pipes.

Key topics and technical requirements

• Scope: Method for assessing GRP pipes under fluctuating internal pressure (cyclic pressure testing).
• Terms: Defines mean pressure, pressure amplitude, cycle frequency, cycle length, leakage and bursting.
• Test principle: Subject a test piece to a specified cyclic pressure (fixed mean, amplitude and frequency) for a set number of cycles or until failure.
• Pressure settings (unless otherwise specified by a referring standard):
  • Mean pressure = PN (nominal pressure of the pipe)
  • Pressure amplitude = ±0.25 × PN (example: for PN10, lower = 7.5 bar, upper = 12.5 bar)
• Cycle frequencies (by nominal size DN):
  • DN ≤ 150: 16 ± 4 cycles/min
  • 150