ISO 7884-2-1987 PDF

Full title and description

St ISO 7884-2-1987 — Glass — Viscosity and viscometric fixed points — Part 2: Determination of viscosity by rotation viscometers. This part specifies methods for continuous viscosity measurement using rotational (Couette and Searle type) viscometers, gives the required calculation formulae and illustrates typical flow fields and a representative rotation viscometer in annexes.

Abstract

Specifies procedures for determining the viscosity of glass (and viscometric fixed points) using rotation viscometers. The method uses the relation between flow-field coefficient, torque and rotational frequency and describes two types of rotational instruments (Couette type with rotating crucible and Searle type with rotating spindle). Annexes include example flow-field formulae and a typical instrument illustration.

General information

• Status: Published / International Standard (confirmed current by ISO review process).
• Publication date: Edition 1 — 1987 (published December 1987).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 81.040.01 (Glass in general).
• Edition / version: Edition 1 (1987).
• Number of pages: 10 (as published by ISO).

Scope

Provides a standardized laboratory method for measuring the dynamic viscosity of glass near viscometric fixed points using rotational viscometers. It covers instrument types (Couette and Searle configurations), required measurements (torque, rotational speed), calculation of viscosity from flow-field coefficients, and includes worked examples and an instrument sketch in annexes. The standard is intended to provide reproducible results for calibration and comparison of glass viscosity data.

Key topics and requirements

• Description of rotation viscometer methods suitable for glass viscosity measurement (Couette and Searle types).
• Definition and use of flow-field coefficients, torque and rotational frequency to calculate viscosity.
• Procedures for continuous measurement under varying shear stresses.
• Annexed formulae for common flow fields (calculation examples) and an illustration of a typical rotational viscometer (annexes A and B).
• Requirements aimed at achieving reproducible viscometric fixed‑point determinations for glass research and calibration.

Typical use and users

Used by glass research laboratories, quality and process control departments in glass manufacturers, calibration and standards laboratories, and academic groups studying glass flow/transition behaviour. The standard supports calibration of viscometers, comparison of viscosity data, and establishing viscometric fixed points for reference glasses.

Related standards

ISO 7884 is a multipart series. Relevant related parts include ISO 7884-1:1987 (Principles for determining viscosity and viscometric fixed points) and other parts of the ISO 7884 series (for example Part 8 — determination of transformation temperature). National adoptions (e.g., DIN ISO 7884-2) republish ISO 7884-2 text as identical national standards.

Keywords

glass; viscosity; viscometric fixed points; rotation viscometer; Couette; Searle; torque; flow-field coefficient; calibration; measurement procedure.

FAQ

Q: What is this standard?

A: ISO 7884-2:1987 is an international standard that specifies how to determine the viscosity of glass using rotational viscometers (Couette and Searle types).

Q: What does it cover?

A: It covers instrument descriptions, measurement procedures (torque and rotational frequency), calculation methods using flow-field coefficients, worked examples and annex illustrations to enable reproducible viscosity measurements and viscometric fixed-point determination.

Q: Who typically uses it?

A: Glass manufacturers, materials and glass research laboratories, calibration/standards laboratories, and academic researchers concerned with glass viscosity and thermal processing. These users apply the method for calibration, quality control and comparative research.

Q: Is it current or superseded?

A: The ISO bibliographic record shows ISO 7884-2:1987 as published and subsequently reviewed under ISO’s review cycle; national adoptions exist (for example DIN ISO 7884-2). Users should check with their national standards body or ISO for the absolute current status or any later revisions before relying on the standard for regulatory or contractual purposes.

Q: Is it part of a series?

A: Yes — ISO 7884 is a multipart series addressing viscosity and viscometric fixed points for glass; Part 1 covers principles and other parts address related measurements (for example ISO 7884-1:1987 and ISO 7884-8:1987).

Q: What are the key keywords?

A: Glass, viscosity, viscometric fixed points, rotation viscometer, Couette, Searle, torque, flow-field coefficient, calibration, measurement procedure.