CEN/TC 19/WG 28 - Fire-resistant hydraulic fluids

This document specifies procedures for the measurement of the extreme pressure (EP) and antiwear
properties of liquid lubricants (categories C, D, F, G, H, M, P of ISO 6743-99), lubricating greases
(ISO 6743-9, category X) and other consistent lubricants. The test conditions are not intended to
simulate particular service conditions, but to provide information over a range of standard conditions
for the purpose of research, development, quality control and fluid ranking. The output is used in
lubricant specifications.

ISO 4404-1:2012 specifies a test method to determine the influence on metals of fire-resistant fluids in categories HFA, HFB and HFC, as classified in ISO 6743-4. ISO 4404-1:2012 evaluates the corrosion protection provided by these fluids towards metal components used in hydraulic systems and installations.

ISO 20783‑1:2011 specifies a test method to assess the stability of emulsions within the category HFAE, as defined in ISO 6743-4, made up with waters having clearly-defined concentrations of salts. This method is applicable only to HFAE fluids and not to HFAS fluids.

This European Standard specifies a method to assess the resistance to oxidation of a phosphate ester fluid under accelerated oxidizing conditions, together with the corrosive effect on copper and steel during ageing. The means of assessment is the change in acidity of the fluid plus absorbent water and the change in mass of test pieces of copper and steel. The precision of the test method applies to changes in acid number up to 3,0 mg KOH/g and changes in mass of up to 3 mg per test piece.
NOTE   Accelerated oxidation of fire-resistant fluids based on phosphate esters is characterized by the formation of acid constituents.
WARNING - The use of this European Standard may involve hazardous materials, operations and equipment. This European Standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this European Standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

This European Standard specifies a method for the determination of the hydrolytic stability of phosphate ester fire-resistant hydraulic fluids. These fluids fall under category HFDR of EN ISO 6743 4 [2] and categories TSD, TGD and TCD of ISO 6743 5 [3].
Hydrolysis results in the formation of acid, measurement of which is effected by using one of the test methods ISO 6618, ISO 6619 or ISO 7537.Results from two different test methods are not necessarily compatible and direct comparison needs caution.
The method is applicable to hydrolytic stability results of up to 0,50 mg KOH/g.
NOTE   This test may also be applied to other non-aqueous fire-resistant fluids, such as those falling into category HFDU of EN ISO 6743 4 [2].
WARNING - The use of this European Standard may involve hazardous materials, operations and equipment. This document does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this document to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

This Technical Report gives guidance on the achievement of compliance with Essential Health and Safety Requirements (EHSR) by the selection of fire-resistant fluids or by other means. It includes consideration of the selection of fluids with lower levels of fire resistance and of mineral oil, with appropriate additional safety measures, where this option may be considered to be most satisfactory during operation.
This Technical Report is concerned with assessing the fire resistance, health properties and effects on the environment, but does not cover requirements for their general physical and chemical properties, which are detailed in EN ISO 12922.

ISO 4263-1:2003 specifies a method for the determination of the ageing behaviour of rust- and oxidation- inhibited mineral oils having a density less than that of water, used as turbine oils (categories TSA, TGA, TSE, TGE of ISO 6743-5, hydraulic oils (categories HL, HM, HR, HV, HG of ISO 6743-4), and circulating oils (category CKB of ISO 6743-6). Oils containing synthetic components can be tested by this procedure, but no precision statement is available yet for such fluids.
This test method is widely used in specifications and is considered of value in comparing the oxidation stability of oils that are 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.

ISO 20763:2004 specifies procedures for the determination of steel-on-steel anti-wear properties of hydraulic fluids by means of performance in a vane-type hydraulic pump. ISO 20763:2004 covers a range of hydraulic fluids, both anhydrous and aqueous, intended for applications where high-speed sliding contacts, such as those found in a vane pump, are encountered.
For mineral oils of categories HM and HV, and fire-resistant fluids of category HFD, the method is applicable to viscosity classes ISO VG 32, ISO VG 46 and ISO VG 68, as specified in ISO 3448. Under different specified conditions, the method is applicable to aqueous fire-resistant hydraulic fluids in categories HFA, HFB and HFC, as specified in ISO 12922, within the same viscosity classes.

ISO 20783-2:2003 specifies three test methods to assess the stability of emulsions within the category HFB, as defined in ISO 6743-4.
Method A describes a method for the determination of stability during storage at ambient temperature [(20 ± 2) °C] and is applicable to HFB and HFB.LT fluids.
Method B describes a method for the determination of stability during storage at medium temperature [(70 ± 2) °C] and is again applicable to HFB and HFB.LT fluids.
Method C describes a method for the determination of stability during storage at low temperature [(-10 ± 2) °C] and is applicable only to HFB.LT fluids.

ISO 20764:2003 specifies two procedures for the preparation of test portions from petroleum and related products boiling above 200 degrees Celsius, which can then be used for the determination of total water content within the range of 3 mg/kg to 1 000 mg/kg. The method is applicable to unused and used lubricating oils, non-aqueous hydraulic fluids and high-boiling solvents. The test portions generated by these procedures are suitable for standard Karl Fischer water-content determinations, such as those described in ISO 6296 and ISO 12937.

ISO 20823:2003 specifies a test method to determine the relative flammability of fluids when contacted with a hot metal surface at a fixed temperature, but it is also possible to gauge fluid ignition temperatures by adjustment of the manifold temperature.
It is primarily used is to assess the resistance to ignition of fire-resistant hydraulic fluids which are, by definition, difficult to ignite.
It may be used with other types of more flammable fluids at lower surface temperatures, but this could significantly increase the hazards of this procedure.

ISO 4263-2:2003 specifies a method for the determination of the ageing behaviour of hydraulic fluids of category HFC as defined in ISO 6743-4 and specified in ISO 12922. The ageing is accelerated by the presence of oxygen, water and metal catalysts at elevated temperature, and the degradation of the fluid is followed by changes in pH value and insolubles content. Other parts of ISO 4263 specify similar procedures for the determination of the ageing behaviour of mineral oils and specified categories of fire-resistant fluids used in hydraulic and other applications.

2010-10-15 EMA: No new information about this project, still cancelled in ISO. WI deleted.
2009-10-27 EMA: WI deleted at ISO, waiting for TC secretary 's reply (see e-mail in WI folder, under Current).
Migrated from Progress Sheet (TC Comment) (2000-07-10): WIs 174 and 189 are the result of the splitting of WI 174 ++ new Tc forecast in BP Bli (991022) ++  New TC forecasts in rev BP (NT/01-01-02)

ISO 20623:2003 specifies procedures for the measurement of the extreme-pressure (EP) and anti-wear properties of lubricating oils and fluids by means of the four ball machine. The conditions of test are those that apply in Europe and other areas that have similar electrical supply characteristics (200 V to 250 V, 50 Hz). In North America, the conditions of test are slightly different, but provide a similar ranking of the lubricating properties of fluids. The test conditions are not intended to simulate particular service conditions, but to provide information over a range of standard conditions for the purpose of research, development, quality control and fluid ranking. The output is used in lubricant specifications.

ISO 20844:2004 specifies a method to assess the resistance to shear stresses applied to mineral oils, synthetic oils and other fluids containing polymers, when passed through a specified diesel injector nozzle. The shear stability is measured by the change in viscosity of the fluid under test, brought about by the polymer degradation during stress. Under normal circumstances, ISO 20844:2004 is applied to hydraulic fluids of categories HR and HV as defined in ISO 6743-4 and specified in ISO 11158, but it may also be applied to fire-resistant hydraulic fluids within categories HFA, HFB, HFC and HFD, with modified conditions as specified in ISO 12922.
No formal correlation has been established between the viscosity loss, or the absence of viscosity loss, obtained using the procedures described in ISO 20844:2004 and that of oils and fluids in actual service. However, ISO 20844:2004 provides standardized conditions for the evaluation of polymer stability under minimized thermal and oxidative stresses. It is normally used by manufacturers of fluids and additives, and users, as a means of ranking existing and potential formulations.
Changes to properties other than viscosity are specified in some specifications, but these are not covered by the procedures specified in ISO 20844:2004.

Migrated from Progress Sheet (TC Comment) (2000-07-10): BTC235/1998: UAP on ISO 6743-4 when available (TA/990104) ++ new TC forecast in BP Bli 991022 ++  New TC forecasts in rev BP (NT/01-01-02)

Migrated from Progress Sheet (TC Comment) (2000-07-10): BTC235/1998: UAP on ISO 12922 when available (TA/990104) ++ new TC forecast in BP Bli 991022 ++  New TC forecasts in rev BP (NT/01-01-02)

ISO 20783-1:2003 specifies a test method to assess the stability of emulsions within the category HFAE, as defined in ISO 6743-4, made up with waters having clearly-defined concentrations of salts. This method is applicable only to HFAE fluids and not to HFAS fluids.

ISO 20843:2003 specifies a test method to determine the pH value of non-flammable fluids within categories HFAE, HFAS and HFC, as classified in ISO 6743-4:1999.

ISO 4404-2:2003 specifies a procedure for the determination of the corrosion-inhibiting properties of non-aqueous hydraulic fluids within the category HFD, as classified in ISO 6743-4.
It provides a qualitative assessment of corrosion of five of the most common metals used in the construction of hydraulic systems, but other metals and/or alloys could be added or substituted for these metals for particular installations.

This part of ISO 4404 specifies a test method to determine the influence on metals of fire-resistant fluids in categories HFA, HFB and HFC, as classified in ISO 6743-4. It evaluates the corrosion protection provided by these fluids towards metal components used in hydraulic systems and installations. A similar technique for fluids in category HFD is described in ISO 4404-2.