ASTM D4293-22

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation: D4293 − 15 D4293 − 22
Standard Specification for
Phosphate Ester Based Ester-Based Fluids for Turbine
Lubrication and Steam Turbine Electro-Hydraulic Control
(EHC) Applications
This standard is issued under the fixed designation D4293; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—Corrected the spacing/formatting of a row in Table 4 editorially in March 2018.
1. Scope*
1.1 This specification covers the minimum requirements for phosphate ester based ester-based fluids for turbine lubricants and
electro-hydraulic control fluids, as delivered.
1.2 The use of this type of fluid is restricted to turbine systems that have been designed or modified to accommodate phosphate
ester fluids.
1.3 This standard does not cover the minimum requirements for in-service phosphate ester fluids for the turbine electro-hydraulic
control (EHC) fluid. These requirements are provided in Guide D8323.
1.4 The values stated in SI units are to be regarded as standard. No For convenience, other units of measurement are
includedprovided in this standard.brackets.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D92 Test Method for Flash and Fire Points by Cleveland Open Cup Tester
D97 Test Method for Pour Point of Petroleum Products
D130 Test Method for Corrosiveness to Copper from Petroleum Products by Copper Strip Test
D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
D664 Test Method for Acid Number of Petroleum Products by Potentiometric Titration
This specification is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.C0.01 on Turbine Oil Monitoring, Problems and Systems.
Current edition approved June 1, 2015Dec. 1, 2022. Published July 2015January 2023. Originally approved in 1983. Last previous edition approved in 20082015 as
ɛ1
D4293 – 83D4293 – 15 (2008). DOI: 10.1520/D4293-15E01.10.1520/D4293-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4293 − 22
D892 Test Method for Foaming Characteristics of Lubricating Oils
D974 Test Method for Acid and Base Number by Color-Indicator Titration
D1169 Test Method for Specific Resistance (Resistivity) of Electrical Insulating Liquids
D1298 Test Method for Density, Relative Density, or API Gravity of Crude Petroleum and Liquid Petroleum Products by
Hydrometer Method
D1401 Test Method for Water Separability of Petroleum Oils and Synthetic Fluids
D2422 Classification of Industrial Fluid Lubricants by Viscosity System
D3427 Test Method for Air Release Properties of Hydrocarbon Based Oils
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
D6304 Test Method for Determination of Water in Petroleum Products, Lubricating Oils, and Additives by Coulometric Karl
Fischer Titration
D7546 Test Method for Determination of Moisture in New and In-Service Lubricating Oils and Additives by Relative Humidity
Sensor
D8112 Guide for Obtaining In-Service Samples of Turbine Operation Related Lubricating Fluid
D8323 Guide for Management of In-Service Phosphate Ester-based Fluids for Steam Turbine Electro-Hydraulic Control (EHC)
Systems
2.2 EN Standards:
EN 14832 Petroleum and Related Products—Determination of the Oxidation Stability and Corrosivity of Fire-resistant
Phosphate Ester Fluids
EN 14833 Petroleum and Related Products—Determination of the Hydraulic Stability of Fire Resistant Phosphate Ester Fluids
2.3 IEC Standard:
IEC 60247 Insulating Liquids—Measurement of Relative Permittivity, Dielectric Dissipation Factor (tan d) and d.c. Resistivity
2.4 Energy Institute Standard:
IP 510 Energy Institute Standard—Petroleum Products—Determination of Organic Halogen Content—Oxidative Microcoulo-
metric Method
2.5 ISO Standards:
ISO 760 Determination of Water—Karl Fischer Method (General Method)
ISO 2160 Petroleum Products—Corrosiveness to Copper—Copper Strip Test
ISO 2592 Determination of Flash and Fire Points—Cleveland Open Cup Method
ISO 3016 Petroleum Products—Determination of Pour Point
ISO 3104 Petroleum Products—Transparent and Opaque Liquids—Determination of Kinematic Viscosity and Calculation of
Dynamic Viscosity
ISO 3170 Petroleum Liquids—Manual Sampling
ISO 3448 Industrial Liquid Lubricants—ISO Viscosity Classification
ISO 3675 Crude Petroleum and Liquid Petroleum Products—Laboratory Determination of Density—Hydrometer Method
ISO 4259 Petroleum Products—Determination and Application of Precision Data in Relation to Methods of Test
ISO 4406 Hydraulic Fluid Power—Fluids—Method for Coding the Level of Contamination by Solid Particles
ISO 6072 Rubber—Compatibility Between Hydraulic Fluids and Standard Elastomeric Materials
ISO 6247 Petroleum Products—Determination of Foaming Characteristics of Lubricating Oils
ISO 6614 Petroleum Products—Determination of Water Separability of Petroleum Oils and Synthetic Fluids
ISO 6618 Petroleum Products and Lubricants—Determination of Acid or Base Number—Colour Indicator Titration Method
ISO 6619 Petroleum Products and Lubricants—Neutralization Number—Potentiometric Titration Method
ISO 7537 Petroleum Products—Determination of Acid Number—Semi-micro Colour-indicator Titration Method
ISO 8068 Lubricants, Industrial Oils and Related Products (Class L)—Family T (Turbines)—Specification for Lubricating Oils
for Turbines
ISO 9001 Quality Management Systems
ISO 9120 Petroleum Products—Determination of Air-release Properties of Steam Turbine and Other Oils—Impinger Method
ISO 10050 Lubricants, Industrial Oils and Related Products (Class L)—Family T (Turbines)—Specifications of Triaryl
Phosphate Ester Turbine Control Fluids (Category ISO-L-TCD)
ISO 11500 Hydraulic Fluid Power—Determination of the Particulate Contamination Level of a Liquid Sample by Automatic
Particle Counting Using the Light-extinction Principle
ISO 12185 Crude Petroleum and Petroleum Products—Determination of Density—Oscillating U-tube Method
Available from British Standards Institution (BSI), 389 Chiswick High Rd., London W4 4AL, U.K., http://www.bsigroup.com or from Deutsches Institut für Normung
e.V.(DIN), Am DIN-Platz, Burggrafenstrasse 6, 10787 Berlin, Germany, http://www.din.de.
Available from International Electrotechnical Commission (IEC), 3, rue de Varembé, P.O. Box 131, CH-1211 Geneva 20, Switzerland, http://www.iec.ch.
Available from Energy Institute, 61 New Cavendish St., London, W1G 7AR, U.K., http://www.energyinst.org.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
D4293 − 22
ISO 14935 Petroleum Products—Determination of Wick Flame Persistence of Fire-resistant Fluids
ISO 15597 Petroleum Products—Determination of Chlorine and Bromine Content—Wavelength X-ray Fluorescence Spectrom-
etry
ISO 20764 Petroleum and Related Products—Preparation of a Test Portion of High-boiling Liquids for the Determination of
Water Content—Nitrogen Purge Method
ISO 20823 Petroleum and Related Products—Determination of the Flammability Characteristics of Fluids in Contact with Hot
Surfaces—Manifold Ignition Test
2.6 General Electric Turbine Manufacturing Standards:
GEK 46357H Steam Turbine-Generator EHC Fluid Specification and Maintenance
2.7 Siemens Turbine Manufacturing Technical Purchasing Specification:
TLV 9012 03 Fire-resistant triaryl phosphate ester hydraulic fluids (TXP-free)
3. Terminology
3.1 Definitions:
3.1.1 For definitions and terms relating to this specification, refer to Terminology D4175.
4. Significance and Use
4.1 Over the last six decades, increasing demand for greater power supply stability forced the steam-turbine manufacturers to
provide a more efficient turbine control system. To accomplish this increased grid stability, faster response to a changing load on
the electric grid, and to provide more precise control, a new system, called Electro-Hydraulic Control (EHC), was developed. This
EHC system is a complex design consisting of two major systems: electronic control systems and a dedicated high-pressure
(typically between 6895 kPa to 13790 kPa (1000 psi to 2000 psi) hydraulic fluid system. In addition, it also has an emergency trip
system, valve controllers, and a monitoring system.
4.2 Triaryl phosphate ester hydraulic fluids have been selected by the turbine manufacturers for the EHC systems primarily due
to their excellent fire-resistance characteristics.
4.3 This is a specification to define specification defines the minimum requirements of phosphate ester fire-resistant fluids for
satisfactory performance in turbine applications. Fire-resistant fluids are more difficult to ignite and show little tendency to
propagate a flame. The term “fire-resistant fluid” does not mean that the fluid will not burn if enough energy is supplied.turbine
applications. Users should be aware that system design differences will result in different rates of fluid degradation and, therefore,
different levels of performance.
4.4 It is critical for the end user to understand that the initial fill or subsequent addition of the high-quality triaryl phosphate ester
fluids to the EHC system will not ensure safe and reliable system performance if the EHC fluid is not adequately prepared and
maintained. For more details, see Guide D8323.
4.5 Before the initial fill, it is essential that the user properly cleans and flushes the EHC system prior to adding the fluid. Refer
to the Guide D8323 standard for more information on flushing.
5. Composition
5.1 In general, phosphate esters are a class of organophosphorus compounds with the general structure O=P(OR) , where R is
alkyl, aryl, or substituted aryl groups. However, in EHC systems and industrial turbine lubrication applications, only triaryl
phosphate fluids, where R is a substituted or unsubstituted phenyl group, are used.
5.2 When approved for use in the above applications, the fluid substituents on the aromatic ring are currently either methyl (-CH )
or tertiary butyl (-C H ) groups.
4 9
5.3 Trixylyl phosphate (TXP) has been designated a Substance of Very High Concern and added to REACH Annex XIV, so its
use is prohibited in the EU as of 2023 unless the end user can obtain an exemption from ECHA for their particular use.
Available from General Electric, 5 Necco St., Boston, MA 02210, https://www.ge.com
Available from Siemens Energy, 4400 N Alafaya Trail, Orlando, FL 32826, https://www.siemens-energy.com.
D4293 − 22
6. Safety Precautions
4.1 The fire safety tests are used to measure and describe the properties of phosphate esters in response to heat and flame under
controlled laboratory conditions and should not be considered or used for the description or appraisal of the fire hazard of the fluids
under actual fire conditions.
6.1 Fires that have occurred in operating turbines have usually been caused by fluid or vapors contacting hot surfaces. For
example, fluid that may leak, spill and be absorbed absorb into unprotected thermal insulation can experience an exothermic
reaction with resultant,resultant potential, rapid temperature increase. The ignition of the absorbed fluid can occur at temperatures
below the fluid auto-ignition temperature.
6.2 Phosphate ester fire-resistant fluids are difficult to ignite and show little tendency to propagate a flame but are not
non-flammable.
6.3 The fire safety tests are used to measure and describe the properties of fire-resistant fluids under controlled laboratory
conditions and should not be considered an exact simulation of the behavior of the fluids under actual fire conditions.
7. Delivery and Storage
7.1 When delivered in originally sealed and properly labeled compatible drums, triaryl phosphate ester fluids should be stored in
temperature-controlled warehouses with adequate protection against airborne contaminants (that is, moisture, dust) and in
accordance with the local safety requirements.
7.2 The fluid should be transported in a manner that will ensure the container’s integrity (that is, drums) and prevent contamination
of the fluid prior to delivery to the user site.
7.3 The manufacturer/supplier shall provide the end user with a document (that is, Certificate of Analysis (COA)) confirming
agreed upon fluid batch performance.
7.4 The fluid manufacturer shall also provide guidance for the supplier and users on the shelf life of the triaryl phosphate ester
fluids stored indoors in original, unopened containers at room temperature.
7.5 Typically, the shelf life of triaryl phosphate ester fluid for EHC systems is at least two (2) years.
7.6 The user may test new triaryl phosphate ester fluids as delivered to ensure that the fluid meets the product technical
requirements. Precautions must be taken to avoid fluid contamination during sampling, and the drums must be properly resealed.
8. Sampling
8.1 Sampling shall be in accordance with the applicable clauses of Practice D4057, ISO 3170, or ISO 3170.Guide D8112Drum
shipments shall be represented by an . If drum sampling is required, use a representative “all-levels sample” obtained by weighted
tube sampling.sampling (Guide D8112).
8.2 Clean, dry, and Use a clean, dry and contamination free sampling apparatus from any substance that might contaminate the
fluid during the sampling process.
8.3 Care shall be taken to ensure that the fluid is adequately mixed properly before samples are withdrawn for the test testing and
that the samples are representative of the whole.whole drum.
8.4 The fluid shall normally meet the specification requirements at the point where when it passes from the supplier to the user
unless other contractual arrangements have been made.
8.5 When testing a fluid against specification requirements, the laboratory should be accredited against the latest version of
ISO 9001 to ensure that the product meets the requirements specified in this standard.
D4293 − 22
9. Elastomer Compatibility Requirements
9.1 This specification follows descriptions and recommendations on elastomer compatibility provided in ISO 6072.
9.2 The limits on elastomer performance given in ISO 6072 are based on the performance of reference elastomers that, while of
similar polymer type, may differ in their chemical composition from their commercial equivalents. It may, therefore, be necessary
to separately check (and approve) the use of specific commercial products before use. This process should be agreed upon by the
turbine builder, the elastomer and the fluid manufacturers and performed at an independent laboratory under ISO 6072 test
conditions.
9.2.1 The elastomer manufacturer should agree to give advanced notice of any change in the elastomer composition to allow time
for testing the new elastomer formulation.
9.3 Caution should be given when performing a compatibility test at elevated temperatures (significantly over 100 °C) as this may
cause t
...