EN ISO 4263-3:2015

Petroleum and related products - Determination of the ageing behaviour of inhibited oils and fluids using the TOST test - Part 3: Anhydrous procedure for synthetic hydraulic fluids (ISO 4263-3:2015)

ISO 4263-3:2015 specifies a method for the determination of the ageing behaviour of synthetic hydraulic fluids of categories HFDU, HEES, HEPG and HETG as defined, for example, in ISO 12922[1] and ISO 15380[2]. The ageing is accelerated by the presence of oxygen and metal catalysts at elevated temperature, and the degradation of the fluid is followed by changes in acid number. Other parts of ISO 4263 specify similar procedures for the determination of ageing behaviour of mineral oils and specified categories of fire-resistant fluids used in hydraulic and other applications.
NOTE          Other signs of fluid deterioration, such as the formation of insoluble sludge, catalyst coil corrosion or change in viscosity, can occur which indicate oxidation of the fluid, but are not reflected in the calculated oxidation lifetime. The correlation of these occurrences with field service is under investigation. This test method may be used to compare the oxidation stability of fluids that are not prone to contamination with water. However, because of the large number of individual field-service applications, the correlation between the results of this test and actual service performance can vary markedly, and is best judged on experience. The precision of this test method for synthetic hydraulic fluids is not known because interlaboratory data are not available. This method might not be suitable for use in specifications or in the event of disputed results as long as these data are not available.

Mineralölerzeugnisse und verwandte Produkte - Bestimmung des Alterungsverhaltens von inhibierten Ölen und Flüssigkeiten unter Anwendung des TOST-Verfahrens - Teil 3: Wasserfreies Verfahren für synthetische Druckflüssigkeiten (ISO 4263-3:2015)

Dieser Teil von ISO 4263 legt ein Verfahren zur Bestimmung des Alterungsverhaltens von synthetischen Druckflüssigkeiten der Klassen HFDU, HEES, HEPG und HETG, die z. B. in ISO 12922 [1] und ISO 15380 [2] definiert sind, fest. Die Alterung wird beschleunigt durch die Anwesenheit von Sauerstoff und Metall-Katalysatoren bei erhöhten Temperaturen, und die Alterung der Flüssigkeit wird über die Änderung der Säurezahl verfolgt. Andere Teile von ISO 4263 legen ähnliche Verfahren für die Bestimmung des Alterungsverhaltens von Mineralöl und spezifizierten Klassen von schwerentflammbaren Flüssigkeiten fest, die in hydraulischen und anderen Anwendungen eingesetzt werden.
ANMERKUNG   Andere Zerfallserscheinungen, wie die Bildung von unlöslichem Schlamm, die Korrosion der Katalysatorwendeln oder die Veränderung der Viskosität können auftreten und sind ein Anzeichen für Oxidationsvorgänge in der Flüssigkeit, die jedoch nicht in die Berechnungen der Oxidationslebensdauer aufgenommen wurden. Die Korrelation dieser Vorkommnisse mit Anwendungen in der Praxis wird noch untersucht. Dieses Prüfverfahren darf zum Vergleich der Oxidationsstabilität von Flüssigkeiten herangezogen werden, für die eine Verunreinigung mit Wasser nicht wahrscheinlich ist. Wegen der großen Anzahl individueller Anwendungen in der Praxis kann jedoch die Übereinstimmung der Ergebnisse dieser Prüfung von der tatsächlichen Leistungsfähigkeit deutlich abweichen und erst im Betriebseinsatz beurteilt werden. Die Präzision für dieses Prüfverfahren für Druckflüssigkeiten ist wegen fehlender Ringversuchsergebnisse nicht bekannt. Dieses Verfahren ist für den Einsatz in Spezifikationen oder im Streitfall nicht geeignet, solange entsprechende Daten nicht verfügbar sind.

Pétrole et produits connexes - Détermination du comportement au vieillissement des fluides et huiles inhibés au moyen de l'essai TOST - Partie 3: Méthode anhydre pour les fluides hydrauliques synthétiques (ISO 4263-3:2015)

L'ISO 4263-3 :2015 spécifie une méthode permettant d'évaluer les caractéristiques de vieillissement des fluides hydrauliques synthétiques des catégories HFDU, HEES, HEPG et HETG définies par exemple dans l'ISO 12922[1] et l'ISO 15380[2]. Le vieillissement est accéléré par la présence d'oxygène et de catalyseurs métalliques à température élevée et la dégradation du fluide est suivie par l'évolution de son indice d'acide. D'autres parties de l'ISO 4263 spécifient des méthodes similaires permettant d'évaluer les caractéristiques de vieillissement des huiles minérales et de catégories spécifiques de fluides difficilement inflammables utilisés dans des applications hydrauliques et autres.
NOTE       D'autres signes peuvent indiquer la détérioration des fluides, comme la formation de dépôts insolubles, la corrosion du bobinage de catalyseurs, ou un changement de viscosité. Cela traduit une oxydation du fluide mais il n'en est pas tenu compte pour la prévision de la durée de résistance à l'oxydation. Une étude est en cours pour essayer d'établir une corrélation entre ces phénomènes et l'utilisation en service. La présente méthode d'essai peut servir à comparer la stabilité à l'oxydation de fluides qui ne sont pas sujets à la contamination par l'eau. Cependant, en raison du très grand nombre de types d'applications sur le terrain, la corrélation des résultats de ces essais avec les performances réelles en service peut varier beaucoup, et il est préférable de faire appel à l'expérience. La fidélité de la présente méthode d'essai n'est pas établie car aucun essai interlaboratoires n'a été effectué. Tant que de tels essais n'ont pas été faits, il se peut que la méthode soit jugée inacceptable pour le contrôle des spécifications ou en cas de litige.

Nafta in sorodni proizvodi - Določevanje staranja inhibiranih olj in tekočin s preskusom TOST - 3. del: Brezvodni postopek za sintetične hidravlične tekočine (ISO 4263-3:2015)

Ta del standarda ISO 4263 določa metodo določevanja staranja sintetičnih hidravličnih tekočin kategorij HFDU, HEES, HEPG in HETG, kot so na primer opredeljene v standardih ISO 12922[1] in ISO 15380[2]. Staranje pospešuje prisotnost kisika in kovinskih katalizatorjev pri povišani temperaturi, pri čemer degradaciji tekočine sledijo spremembe v kislinskem številu. Drugi deli standarda ISO 4263 določajo podobne postopke za določevanje staranja mineralnih olj in navedenih kategorij negorljivih tekočin, ki se uporabljajo v hidravličnih ali drugih sistemih.
OPOMBA Pojavijo se lahko tudi drugi znaki kvarjenja tekočine, ki označujejo oksidacijo tekočine, kot je nastanek netopnega blata, korozija tuljave v katalizatorju ali sprememba viskoznosti, vendar ti niso vključeni v izračunano življenjsko dobo oksidacije. Trenutno poteka raziskava povezave teh pojavitev s storitvami na terenu. Ta preskusna metoda se lahko uporabi za primerjavo oksidacijske stabilnosti tekočin, ki niso nagnjene k onesnaženju z vodo. Vendar je lahko zaradi velikega števila posameznih uporab na terenu povezava med rezultati tega preskusa in dejanskim delovanjem storitve zelo različna, pri čemer jo je priporočljivo presoditi na podlagi izkušenj. Natančnost te preskusne metode za sintetične hidravlične tekočine ni znana, saj medlaboratorijski podatki niso na voljo. Ta metoda v primeru, da ti podatki niso na voljo, morda ni primerna za uporabo v specifikacijah ali v primeru sporov pri razlagi rezultatov.

General Information

• Status: Published
• Publication Date: 08-Dec-2015
• Withdrawal Date: 29-Jun-2016
• ICS: 75.120 - Hydraulic fluids
• Technical Committee: CEN/TC 19 - Petroleum products, lubricants and related products
• Drafting Committee: CEN/TC 19 - Petroleum products, lubricants and related products
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 09-Dec-2015
• Completion Date: 09-Dec-2015
• Ref Project: SIST EN ISO 4263-3:2016 - Petroleum and related products - Determination of the ageing behaviour of inhibited oils and fluids using the TOST test - Part 3: Anhydrous procedure for synthetic hydraulic fluids (ISO 4263-3:2015)

Relations

• Replaces: EN ISO 4263-3:2010 - Petroleum and related products - Determination of the ageing behaviour of inhibited oils and fluids using the TOST test - Part 3: Anhydrous procedure for synthetic hydraulic fluids (ISO 4263-3:2010)
• Effective Date: 04-Apr-2012

Overview

EN ISO 4263-3:2015 specifies an anhydrous TOST test method to determine the ageing (oxidation) behaviour of synthetic hydraulic fluids. It targets fluids of categories HFDU, HEES, HEPG and HETG (as referenced in ISO 12922 and ISO 15380). The method accelerates ageing by exposing a test portion to oxygen and a steel/copper catalyst at elevated temperature and follows degradation by measuring changes in acid number (TAN) until a defined endpoint is reached.

Key topics and requirements

• Test principle: accelerated oxidation in the absence of light and water, using oxygen and a metal catalyst coil at an elevated temperature (95 °C).
• End points: test duration recorded when either:
  • TAN reaches 2.0 mg KOH/g, or
  • TAN increases by 2.0 mg KOH/g from the initial value.
• Measurements: periodic removal of aliquots and determination of acid number (semi‑micro titration per referenced methods).
• Scope limits:
  • Intended for fluids not prone to water contamination (anhydrous procedure).
  • Other deterioration indicators (insoluble sludge, catalyst corrosion, viscosity change) may occur but are not reflected in the calculated oxidation lifetime.
  • Precision for synthetic hydraulic fluids is currently unknown due to lack of interlaboratory data; caution advised for use in formal specifications or dispute resolution.
• Procedure details included: reagents and apparatus, sampling, cleaning and preparation of catalyst coils and glassware, test execution, calculations, expression of results, reporting.
• Annexes: thermometer specs, catalyst packaging/storage, insolubles determination, coil appearance rating, metals content determination.
• Normative references: ISO 3170, ISO 3696, ISO 7537, EN 10130, etc.

Practical applications

• Comparative oxidation stability testing during product development and R&D for synthetic hydraulic fluids.
• Quality control and batch screening when water contamination is not expected.
• Material selection and performance comparison for hydraulic systems where long-term oxidation resistance is critical (mobile and industrial hydraulics).
• Investigation of oxidation-related failures as part of laboratory analysis (complementary to viscosity, insolubles and corrosion observations).

Who should use this standard

• Hydraulic fluid manufacturers and formulators
• Test and quality control laboratories
• OEMs and hydraulic system designers
• Tribologists and lubrication engineers
• Research labs studying oxidation and additive performance

Related standards

• Other parts of ISO 4263 (mineral oils, HFC fluids, industrial gear oils)
• ISO 12922, ISO 15380 (fluid categories and classification)
• ISO 3170, ISO 3696, ISO 7537 (sampling, water quality, acid number determination)

Keywords: EN ISO 4263-3, TOST test, oxidation stability, synthetic hydraulic fluids, TAN, HFDU, HEES, HEPG, HETG, ageing behaviour, anhydrous procedure.

Standards Content (Sample)

SLOVENSKI STANDARD
01-februar-2016
1DGRPHãþD
SIST EN ISO 4263-3:2010
1DIWDLQVRURGQLSURL]YRGL'RORþHYDQMHVWDUDQMDLQKLELUDQLKROMLQWHNRþLQV
SUHVNXVRP7267GHO%UH]YRGQLSRVWRSHN]DVLQWHWLþQHKLGUDYOLþQHWHNRþLQH
,62
Petroleum and related products - Determination of the ageing behaviour of inhibited oils
and fluids using the TOST test - Part 3: Anhydrous procedure for synthetic hydraulic
fluids (ISO 4263-3:2015)
Mineralölerzeugnisse und verwandte Produkte - Bestimmung des Alterungsverhaltens
von inhibierten Ölen und Flüssigkeiten unter Anwendung des TOST-Verfahrens - Teil 3:
Wasserfreies Verfahren für synthetische Druckflüssigkeiten (ISO 4263-3:2015)
Pétrole et produits connexes - Détermination du comportement au vieillissement des
fluides et huiles inhibés au moyen de l'essai TOST - Partie 3: Méthode anhydre pour les
fluides hydrauliques synthétiques (ISO 4263-3:2015)
Ta slovenski standard je istoveten z: EN ISO 4263-3:2015
ICS:
75.120 +LGUDYOLþQLIOXLGL Hydraulic fluids
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 4263-3
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2015
EUROPÄISCHE NORM
ICS 75.120 Supersedes EN ISO 4263-3:2010
English Version
Petroleum and related products - Determination of the
ageing behaviour of inhibited oils and fluids using the
TOST test - Part 3: Anhydrous procedure for synthetic
hydraulic fluids (ISO 4263-3:2015)
Pétrole et produits connexes - Détermination du Mineralölerzeugnisse und verwandte Produkte -
comportement au vieillissement des fluides et huiles Bestimmung des Alterungsverhaltens von inhibierten
inhibés au moyen de l'essai TOST - Partie 3: Méthode Ölen und Flüssigkeiten unter Anwendung des TOST-
anhydre pour les fluides hydrauliques synthétiques Verfahrens - Teil 3: Wasserfreies Verfahren für
(ISO 4263-3:2015) synthetische Druckflüssigkeiten (ISO 4263-3:2015)
This European Standard was approved by CEN on 24 October 2015.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4263-3:2015 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
European foreword
This document (EN ISO 4263-3:2015) has been prepared by Technical Committee ISO/TC 28
"Petroleum products and lubricants" in collaboration Technical Committee CEN/TC 19 “Gaseous and
liquid fuels, lubricants and related products of petroleum, synthetic and biological origin” the
secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by June 2016, and conflicting national standards shall be
withdrawn at the latest by June 2016.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document supersedes EN ISO 4263-3:2010.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 4263-3:2015 has been approved by CEN as EN ISO 4263-3:2015 without any
modification.
INTERNATIONAL ISO
STANDARD 4263-3
Third edition
2015-11-15
Petroleum and related products —
Determination of the ageing
behaviour of inhibited oils and fluids
using the TOST test —
Part 3:
Anhydrous procedure for synthetic
hydraulic fluids
Pétrole et produits connexes — Détermination du comportement au
vieillissement des fluides et huiles inhibés au moyen de l’essai TOST —
Partie 3: Méthode anhydre pour les fluides hydrauliques synthétiques
Reference number
ISO 4263-3:2015(E)
©
ISO 2015
ISO 4263-3:2015(E)
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2015 – All rights reserved

ISO 4263-3:2015(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Principle . 1
4 Reagents and materials . 2
5 Apparatus . 3
6 Sampling .11
7 Preparation of materials and apparatus .12
7.1 Cleaning the catalyst wire .12
7.2 Preparation of catalyst coil .12
7.3 Storage of the catalyst coil.12
7.4 Cleaning new glassware .12
7.5 Cleaning used glassware .12
7.6 Cleaning aliquot-removal device .12
8 Procedure.13
9 Calculation .14
10 Expression of results .15
11 Precision .15
11.1 General .15
11.2 Repeatability, r .15
11.3 Reproducibility, R  .16
11.4 Reproducibility with duplicate tests .16
12 Test report .16
Annex A (normative) Liquid-in-glass thermometer specifications .17
Annex B (normative) Procedure for packaging and storage of catalyst coils .18
Annex C (informative) Method for the determination of the insolubles content of mineral
oils and anhydrous synthetic fluids .19
Annex D (informative) Appearance rating of catalyst coil wires .22
Annex E (informative) Determination of metals content .23
Bibliography .24
ISO 4263-3:2015(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 28, Petroleum products and related products of
synthetic or biological origin.
This third edition cancels and replaces the second edition (ISO 4263-3:2010). The main change is the
revision of the calculation in Clause 9 to include calculations for both a test oil reaching a TAN of 2,0 mg
KOH per gram and for a test oil reaching an increase of TAN of 2,0 mg KOH per gram. In addition, the
inclusion of HETG and exclusion of HFDR from the scope have been adopted.
ISO 4263 consists of the following parts, under the general title Petroleum and related products —
Determination of the ageing behaviour of inhibited oils and fluids using the TOST test:
— Part 1: Procedure for mineral oils
— Part 2: Procedure for category HFC hydraulic fluids
— Part 3: Anhydrous procedure for synthetic hydraulic fluids
— Part 4: Procedure for industrial gear oils
NOTE As of the date of publication of this part of ISO 4263, the titles of parts 1, 2 and 4 started with Petroleum
and related products – Determination of the ageing behaviour of inhibited oils and fluids — TOST test.
iv © ISO 2015 – All rights reserved

INTERNATIONAL STANDARD ISO 4263-3:2015(E)
Petroleum and related products — Determination of the
ageing behaviour of inhibited oils and fluids using the
TOST test —
Part 3:
Anhydrous procedure for synthetic hydraulic fluids
WARNING — The use of this part of ISO 4263 can involve hazardous materials, operations
and equipment. This part of ISO 4263 does not purport to address all of the safety problems
associated with its use. It is the responsibility of the user of this part of ISO 4263 to establish
appropriate safety and health practices and determine the applicability of regulatory limitations
prior to use.
1 Scope
This part of ISO 4263 specifies a method for the determination of the ageing behaviour of synthetic
[1]
hydraulic fluids of categories HFDU, HEES, HEPG and HETG as defined, for example, in ISO 12922
[2]
and ISO 15380 . The ageing is accelerated by the presence of oxygen and metal catalysts at elevated
temperature, and the degradation of the fluid is followed by changes in acid number. Other parts of
ISO 4263 specify similar procedures for the determination of ageing behaviour of mineral oils and
specified categories of fire-resistant fluids used in hydraulic and other applications.
NOTE Other signs of fluid deterioration, such as the formation of insoluble sludge, catalyst coil corrosion
or change in viscosity, can occur which indicate oxidation of the fluid, but are not reflected in the calculated
oxidation lifetime. The correlation of these occurrences with field service is under investigation. This test
method may be used to compare the oxidation stability of fluids that are not prone to contamination with water.
However, because of the large number of individual field-service applications, the correlation between the results
of this test and actual service performance can vary markedly, and is best judged on experience. The precision of
this test method for synthetic hydraulic fluids is not known because interlaboratory data are not available. This
method might not be suitable for use in specifications or in the event of disputed results as long as these data are
not available.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 3170, Petroleum liquids — Manual sampling
ISO 3696:1987, Water for analytical laboratory use — Specification and test methods
ISO 7537, Petroleum products — Determination of acid number — Semi-micro colour-indicator
titration method
EN 10130:2007, Cold rolled low carbon steel flat products for cold forming — Technical delivery conditions
3 Principle
A test portion is reacted, in the absence of light, at 95 °C with oxygen and a steel and copper catalyst coil.
Small aliquots of the fluid are withdrawn at regular intervals and the acid number is measured (see the
Note in Clause 1). The test is continued until either an acid number of 2,0 mg of potassium hydroxide
ISO 4263-3:2015(E)
(KOH) per gram is reached or until an increase of 2,0 mg of potassium hydroxide (KOH) per gram of test
portion is reached and the number of hours is recorded as the oxidation lifetime. For some requirements,
the test may be discontinued at a fixed number of hours (e.g. 500 h or 1 000 h) when the value of the acid
number has still not either reached or increased by 2,0 mg of KOH per gram of test portion.
4 Reagents and materials
4.1 Water, unless otherwise specified, in accordance with the requirements of grade 2 of ISO 3696.
Potable water means tap water, unless normal piped supplies are contaminated with particulate or high
levels of soluble mineral content.
4.2 Heptane, (C H ) of minimum purity 99,75 %.
7 16 ,
4.3 Acetone, (CH COCH ), of general purpose reagent grade (GPR).
3 3
4.4 Propan-2-ol, (CH CHOHCH ), of general purpose reagent grade (GPR).
3 3
4.5 Oxygen, of minimum purity 99,5 %, supplied through a pressure regulation system adequate to
maintain the specified flow rate throughout the test duration.
Supply from an oxygen cylinder should be via a two-stage regulation system and a needle valve to
improve the consistency of gas-flow regulation.
WARNING — Use oxygen only with equipment validated for oxygen service. Do not allow oil or
grease to come into contact with oxygen and clean and inspect all regulators, gauges and control
equipment. Check the oxygen-supply system regularly for leaks. If a leak is suspected, turn off
immediately and seek qualified assistance.
4.6 Cleaning solutions.
4.6.1 Strong oxidizing acid solution.
The reference strong oxidizing cleaning solution on which precision was based, is chromosulfuric acid
(see the following warning), but alternative non-chromium containing solutions, such as ammonium
persulfate in concentrated sulfuric acid (8 g/l), have been found to give satisfactory cleanliness. A 10 %
solution of three parts of hydrochloric acid (1 mol/l) and one part of orthophosphoric acid (concentrated
GPR grade) removes iron oxide deposits.
WARNING — Chromosulfuric acid is a health hazard. It is toxic, a recognized carcinogen as it
contains Cr (VI) compounds, highly corrosive and potentially hazardous in contact with organic
materials. When using a chromosulfuric acid cleaning solution, eye protection and protective
clothing are essential. Never pipette the cleaning solution by mouth. After use, do not pour
cleaning solution down the drain, but neutralize it with great care owing to the concentrated
sulfuric acid present, and dispose of it in accordance with standard procedures for toxic
laboratory waste (chromium is highly dangerous to the environment).
Strongly oxidizing acid cleaning solutions that are chromium-free are also highly corrosive and
potentially hazardous in contact with organic materials, but do not contain chromium which has special
disposal problems.
4.6.2 Surfactant cleaning fluid.
A proprietary strong surfactant cleaning fluid is a preferred alternative for example a combination of
non-ionic with anionic detergent pH of 9,5 to 11,0.
2 © ISO 2015 – All rights reserved

ISO 4263-3:2015(E)
4.7 Catalyst wires.
4.7.1 Low-metalloid steel wire, of diameter 1,60 mm ± 0,05 mm, made of low carbon steel to
EN 10130 DC04, soft bright annealed and free from rust.
4.7.2 Copper wire, of diameter 1,63 mm ± 0,05 mm, made of electrolytic copper wire of 99,9 %
[3]
minimum purity, conforming to EN 13601 . Soft copper wire of an equivalent grade may also be used.
4.8 Abrasive cloth, made of silicon carbide of 150 µm (100 grit) with cloth backing, or an equivalent
grade of abrasive cloth.
4.9 Absorbent cotton.
5 Apparatus
5.1 Oxidation cell, consisting of a large test tube of borosilicate glass. A mushroom condenser and
oxygen-delivery tube, also of borosilicate glass, fit into the test tube. The design and dimensions shall be
as illustrated in Figure 1. The stages of preparation of the oxygen-delivery tube are illustrated in Figure 2.
5.2 Heating bath, consisting of a thermostatically controlled bath capable of maintaining the hydraulic
fluid test portion in the oxidation cell at 95,0 °C ± 0,2 °C. It shall be large enough to hold the required
number of oxidation cells (5.1) immersed in the heat transfer medium to a depth of 355 mm ± 10 mm. It
shall be constructed to ensure that light is excluded from the test portions during the test. If a fluid bath
is used, it shall be fitted with a suitable stirring system to provide a uniform temperature throughout
the bath. If the fluid bath is fitted with a top, the total length of the oxidation cell within the bath shall
be 390 mm ± 10 mm. If a metal-block bath is used, the heaters shall be distributed so as to produce a
uniform temperature throughout the bath, and the holes in the block shall have a minimum diameter of
50 mm and a depth, including any insulating cover, of 390 mm ± 10 mm.
5.3 Flowmeter, capable of measuring 3,0 l/h with an accuracy of ± 0,1 l/h.
ISO 4263-3:2015(E)
Dimensions in millimetres (unless otherwise indicated)
Key
1 glass condenser
2 oxygen delivery tube
3 fluid sample
4 catalyst coil
5 radius of bottom cell
Figure 1 — Oxidation cell
4 © ISO 2015 – All rights reserved

ISO 4263-3:2015(E)
Dimensions in millimetres
a) First stage — Delivery tube base preparation
b) Second stage — Delivery tube middle section preparation
Figure 2 — Construction of the oxygen delivery lead-in tube (continued on the next page)

ISO 4263-3:2015(E)
Dimensions in millimetres
c) Third stage — Delivery tube final assembly
Key
a
Bend over mandrel of diameter 26 mm.
b
Grind end of tube flat.
c
Refers to the outer diameter.
Figure 2 — Construction of the oxygen delivery lead-in tube
5.4 Temperature-measurement devices.
5.4.1 Heating bath, the temperature in liquid heating baths shall be measured by either a liquid-in-
glass thermometer meeting the requirements of the specification given in Annex A, or an equivalent
temperature-measurement system readable to ± 0,1 °C and graduated in 0,1 °C increments. For metal-
block heating baths, a temperature-measurement system, with possibly more than one device of the
same readability and accuracy, is required.
5.4.2 Oxidation cell, the temperature in the oxidation cell shall be measured by either a liquid-in-
glass thermometer meeting the requirements of the specification given in Annex A, or an equivalent
temperature-measurement system readable to ± 0,1 °C and calibrated to better than ± 0,1 °C.
5.4.3 Thermometer bracket, if a liquid-in-glass thermometer is used in the oxidation cell, it shall be
suspended by means of a bracket as illustrated in Figure 3. The thermometer is held in the bracket by either
two fluoro-elastomer O-rings of approximately 5 mm diameter, or by the use of thin, stainless steel wire.
6 © ISO 2015 – All rights reserved

ISO 4263-3:2015(E)
Dimensions in millimetres
a) Bracket (finished) b) Development of bracket
Material: Thickness 0,792 mm, stainless steel
Figure 3 — Thermometer bracket
5.5 Wire-coiling mandrel, as illustrated in Figure 4, is used to produce the double spiral of copper
and steel wire. The mandrel is included in a suitable winding device.
Dimensions in millimetres
ISO 4263-3:2015(E)
Figure 4 — Catalyst coil mandrel (continued on the next page)
Dimensions in millimetres
8 © ISO 2015 – All rights reserved

ISO 4263-3:2015(E)
Figure 4 — Catalyst coil mandrel (continued on the next page)
ISO 4263-3:2015(E)
Dimensions in millimetres
Key
c
1 M6 × 1,0 × 12,7 hexagon head steel screw Material: bronze.
(or equivalent)
d
2 M8 × 1,25 × 12,7 hexagon head steel screw Holes (2) tap M8 × 1,25 (or equivalent).
(or equivalent)
e
3 vice jaws Hole tap M5 × 0,8 (or equivalent).
f
4 M5 × 0,8 × 5 steel grub screw (or equivalent) Pitch.
g
5 catalyst wires Pitch height.
a h
Material: steel. Hole tap M6 × 1,0 (or equivalent).
b i
Material: brass. 6 TPI double thread.
Figure 4 — Catalyst coil mandrel
5.6 Oxygen-supply tube, flexible polyvinylchloride (PVC) tubing of approximately 6,4 mm inside
diameter and 1,5 mm wall thickness, is required to deliver oxygen to the oxidation cell.
5.7 Aliquot-removal devices, depending upon the size and frequency of removal of aliquots of the
test portion for analysis, a selection of devices is required. Glass syringes, fitted with Luer connectors
and stainless steel needles, or long pipettes fitted with suitable pipette fillers, are suitable. These may be
inserted via a sampling tube (5.9) fitted through the condenser. Aliquot sizes are generally in the range of
2 ml to 10 ml, and the devices shall be capable of removing the required aliquot ± 0,2 ml.
5.8 Aliquot containers, small, dark glass vials of 5 ml to 10 ml capacity, fitted with close-fitting
polyethylene caps.
5.9 Sampling tube, stainless steel tubing, 2,11 mm outside diameter, 1,60 mm inside diameter,
610 mm ± 2 mm long, with one end finished at 90° and the other end fitted with an optional female Luer
c
...