ISO 13966-1998 PDF

Full title and description

St ISO 13966-1998 — Thermoplastics pipes and fittings — Nominal ring stiffnesses. This international standard establishes the nominal ring-stiffness (SN) classification system used to designate minimum ring-stiffness requirements for thermoplastic pipes and fittings with circular cross-sections.

Abstract

ISO 13966:1998 defines a range of nominal ring-stiffness classes (expressed as SN values) and the convention for designating those classes for thermoplastic pipes and fittings. It is intended to provide a common, rounded numerical designation that simplifies specification and comparison of components’ resistance to radial deformation under external loading (for example, soil or traffic loads on buried piping). The standard is short (2 pages) and points to specific test methods for measuring actual ring stiffness.

General information

• Status: Published — international standard (confirmed in ISO periodic review; edition remains current as reviewed/confirmed in recent review).
• Publication date: July 1998 (published 09 July 1998).
• Publisher: International Organization for Standardization (ISO), technical committee ISO/TC 138 (Plastics pipes, fittings and valves for the transport of fluids).
• ICS / categories: 23.040.20 (Plastics pipes); 23.040.45 (Plastics fittings).
• Edition / version: Edition 1 (1998).
• Number of pages: 2.

Scope

Specifies a range of nominal ring-stiffness classes and the method of designation for components of thermoplastic pipe systems having a circular cross-section. ISO 13966 does not itself define the detailed test procedure for measuring ring stiffness; instead it refers to the appropriate test standards for pipes and for fittings. It is applicable where a simple, rounded SN classification is required in specifications and product markings.

Key topics and requirements

• Definition and designation of nominal ring stiffness (SN) classes used to express minimum ring stiffness of pipes and fittings.
• Typical nominal classes used in practice (examples frequently used in related ISO product standards: SN 2, SN 4, SN 8, SN 16 — manufacturers and product standards specify which classes apply by diameter and application).
• Reference to test methods for determining actual ring stiffness: ISO 9969 for pipes and ISO 13967 for fittings (these are normative test-method references used to verify conformance to the nominal SN classes).
• Use of preferred-number series (ISO 3) when relating numeric values to standardized classes and for rounding/selection of nominal values.
• Units and interpretation: ring stiffness is expressed in kN/m² (or kN/m in some contexts) and SN refers to the rounded nominal value (for example SN 8 indicates ~8 kN/m² minimum ring stiffness within the applicable diameter range).

Typical use and users

Used by pipe and fitting manufacturers, testing laboratories, system designers and specifiers, procurement professionals, and regulatory bodies to classify and specify the ring-stiffness performance of thermoplastic piping components. It is commonly referenced in product specifications, installation standards for buried drainage/wastewater systems, and in conformity testing programs.

Related standards

Normative and related references commonly associated with ISO 13966: ISO 9969 (Thermoplastics pipes — Determination of ring stiffness), ISO 13967 (Thermoplastics fittings — Determination of ring stiffness), ISO 3 (Preferred numbers), and other ISO/TC 138 product standards (for example product standards that specify applicable SN classes for particular materials or applications). Regional and product standards for non-pressure drainage and other applications (which refer to SN classes) are also commonly associated.

Keywords

nominal ring stiffness; ring stiffness; SN class; thermoplastics pipes; thermoplastics fittings; ISO 13966; ISO/TC 138; ISO 9969; ISO 13967; preferred numbers.

FAQ

Q: What is this standard?

A: ISO 13966:1998 is the ISO standard that defines nominal ring-stiffness classes (the "SN" designation) for thermoplastic pipes and fittings with circular cross-sections. It provides the classification and designation convention; detailed test methods are given in separate standards.

Q: What does it cover?

A: It covers the range of nominal ring-stiffness classes and their designation for thermoplastic pipes and fittings. It applies where a nominal SN classification is needed for specification or marking; it does not itself describe the laboratory test procedure for measuring ring stiffness (see ISO 9969 and ISO 13967 for test methods).

Q: Who typically uses it?

A: Manufacturers, test laboratories, designers, standards writers, procurement/specification professionals, and authorities who need a standardized, simple way to specify or compare ring-stiffness performance of thermoplastic piping components.

Q: Is it current or superseded?

A: The original publication date is July 1998 (Edition 1). The ISO record shows the publication remains the published edition and has been subject to ISO systematic reviews (the edition has been confirmed in periodic reviews). Users should check national or product-specific updates that may apply alongside this ISO classification.

Q: Is it part of a series?

A: It is part of the body of ISO/TC 138 standards addressing plastics pipes and fittings. It is closely linked to test-method standards (ISO 9969 for pipes, ISO 13967 for fittings) and sits alongside product-specific ISO standards that adopt SN classes for particular materials and applications.

Q: What are the key keywords?

A: 'Nominal ring stiffness', 'SN', 'ring stiffness', 'thermoplastics pipes', 'thermoplastics fittings', 'ISO 13966', 'ISO 9969', 'ISO 13967'.