ISO 6259-1:2015

Overview

ISO 6259-1:2015 - Thermoplastics pipes: Determination of tensile properties - Part 1: General test method defines a short-term tensile test procedure for thermoplastic pipes. The standard specifies how to determine key tensile properties - stress at yield and elongation at break - for all types of thermoplastic pipes, regardless of their intended use. It is intended primarily as a material-in-pipe form test useful for research, development and process control, but not as a predictor of long-term performance (e.g., impact, creep, fatigue).

Key topics and technical requirements

• Scope and applicability: Applies to all thermoplastics pipes; complements material standards by testing pipes “as supplied.”
• Test principle: Longitudinal test pieces are cut or machined from pipe and tested in tension to measure yield stress and elongation.
• Test piece preparation:
  • Strips are cut parallel to the pipe axis, equally distributed around the circumference.
  • Thin-walled pipes: die cutting; thick-walled pipes: machining.
  • Minimum number of strips depends on nominal outside diameter (example: for 15 < dn ≤ 32 mm use 2 strips; 32 < dn ≤ 63 mm use 3; >63 mm use 5).
• Apparatus & accuracy:
  • Tensile-testing machine complying with ISO 5893.
  • Load indicator accuracy within 1%; extensometer capable of measuring deformation to 1% accuracy.
  • Micrometer or equivalent reading to 0.01 mm for width/thickness measurements.
• Test conditions: Conditioning, specified test speed, use of grips and extensometer to avoid slippage or premature failure.
• Results & reporting: Express results as stress at yield and elongation at break; statistical treatment and retest rules are specified.

Practical applications and who uses it

ISO 6259-1:2015 is used by:

• Pipe manufacturers for material and process control
• Independent testing laboratories performing quality verification
• R&D teams evaluating new thermoplastic formulations or pipe designs
• Specifiers, procurement and certification bodies requiring standard tensile data for compliance It is particularly useful where tensile behavior of the pipe form (not sheet material) is required for specification, comparison or development.

Related standards

• ISO 6259-2: Pipes made of PVC (PVC‑U, PVC‑C, PVC‑HI)
• ISO 6259-3: Polyolefin pipes
• ISO 527: Tensile testing of plastics (sheet form - basis for ISO 6259)
• ISO 5893: Tensile test equipment specification
• ISO 1167, ISO 2602, ISO 7500‑1 (normative or referenced in test procedures)

Keywords: ISO 6259-1:2015, thermoplastics pipes tensile test, stress at yield, elongation at break, pipe testing, tensile properties, pipe material testing.