ISO 1136-1976 rus PDF

Full title and description

ISO 1136:1976 — Wool — Determination of mean diameter of fibres — Air permeability method. This International Standard specifies an air‑permeametry procedure for estimating the mean fibre diameter (mean fibre fineness) of wool by measuring air flow through a weighed bundle of fibres and converting the measured permeability to a mean diameter. A Russian language entry/record for this standard is available in ISO catalogues and in national catalogues.

Abstract

The method is based on the Kozeny relation linking porosity/permeability to particle size. A known mass of wool fibres is placed in a measuring chamber of known volume; a controlled air flow (or pressure drop) is applied and the permeability reading is converted to a mean fibre diameter using calibration data, graphs or tables provided in the standard. The procedure is intended for clean, unmedullated wool in an open, dispersed state and includes requirements for specimen preparation, apparatus calibration and limitations of the method.

General information

• Status: Withdrawn (superseded / replaced).
• Publication date: November 1976 (Edition 1, 1976).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 59.060.10 (Natural fibres / textiles).
• Edition / version: Edition 1 (1976). Replaced by ISO 1136:2015 (Edition 2, 2015).
• Number of pages: Approximately 8–10 pages (original publication; bibliographic records vary).

Scope

Specifies an air‑permeability based test method to determine the mean diameter of wool fibres. It applies principally to clean, unmedullated wool fibres dispersed in an open state (for example combed slivers). The method is best suited to standard/combed lots and is less accurate for heavily medullated wools or certain lambswools; solvent‑cleaning limits and specimen conditioning are addressed in the standard. Note: the original 1976 method has since been reviewed and the modern technical requirements and limits are set out in ISO 1136:2015.

Key topics and requirements

• Principle — measurement of air permeability through a weighed fibre bundle and conversion to mean fibre diameter using calibration/Kozeny‑based relations.
• Apparatus — measuring chamber of known volume, controlled air‑flow or pressure‑drop device, and a calibrated scale or transducer for flow/pressure.
• Specimen preparation — requirements for sample mass, cleaning (organic solvent limits), dispersion and conditioning.
• Calibration and conversion — use of calibration tables/graphs or instrument calibration standards to convert permeability readings into mean diameter values.
• Limitations and applicability — notes on medullation, lambswool, heavy dyes and other conditions that affect accuracy.
• Traceability and references — links to later revisions and related national standards (some national standards reference or adapt ISO 1136:1976).

Typical use and users

Used by textile testing laboratories, wool classing and grading services, fiber research institutes, yarn/spinning mills and instrument manufacturers for routine or comparative determination of mean fibre diameter. Historically important for producers and buyers who required an air‑flow based, rapid estimate of mean fibre fineness before instrument alternatives (optical/laser methods) became widespread.

Related standards

Revised and replaced by ISO 1136:2015 (Air permeability method, second edition). National standards and methods (for example certain GOSTs and later national textile test methods) reference ISO 1136:1976 or the later 2015 edition for air‑flow methods to determine mean fibre diameter. International wool and textile organizations publish complementary calibration and method documents (IWTO / Interwoollabs calibration standards) that are commonly used with air‑flow methods.

Keywords

wool; fibre diameter; mean fibre diameter (MFD); air permeability; air‑flow method; Kozeny equation; fibre fineness; textile testing; ISO 1136; wool testing.

FAQ

Q: What is this standard?

A: ISO 1136:1976 is an International Standard that defined an air‑permeability (air‑flow) procedure for estimating the mean diameter of wool fibres by measuring air flow through a weighed bundle of fibres.

Q: What does it cover?

A: It covers the test principle, required apparatus, specimen preparation and conditioning, calibration and conversion of permeability readings to mean fibre diameter, and notes on the method's limits of applicability. The 1976 edition was explicit about chamber volumes, specimen masses and the Kozeny‑based conversion approach; later editions provide updated technical details.

Q: Who typically uses it?

A: Textile test laboratories, wool classers and graders, research institutes, processors and instrument manufacturers who need to characterise wool fibre fineness or compare lots for processing and valuation.

Q: Is it current or superseded?

A: ISO 1136:1976 has been withdrawn and superseded by ISO 1136:2015 (edition 2). For current technical requirements and limits, users should consult ISO 1136:2015 or their national adoption of that edition.

Q: Is it part of a series?

A: ISO 1136 is part of the body of ISO/TC 38 textile standards and is related to other wool and fibre measurement standards and calibration documents (including IWTO and inter‑laboratory calibration standards). The 2015 revision continues that lineage.

Q: What are the key keywords?

A: Mean fibre diameter (MFD), air permeability, air‑flow method, Kozeny equation, wool testing, fibre fineness, ISO 1136.