Standard No.:	GB 23971-2025
English Name:	Organic heat transfer fluids
Chinese Name:	有机热载体
Chinese Classification:	E34    Lubricating oil
Professional Classification:	GB    National Standard
Source Content Issued by:	SAMR; SAC
Issued on:	2025-10-05
Implemented on:	2026-11-1
Status:	to be valid
Superseding:	GB 23971-2009 Heat transfer fluids
Target Language:	English
File Format:	PDF
Word Count:	14500 words
Translation Price(USD):	435.0
Delivery:	via email in 1 business day

GB 23971-2025 Organic heat transfer fluids +English, Anglais, Englisch, Inglés, えいご WARNING: The production, storage, transportation, and use of products as specified in this document may be hazardous, if suitable precautions are not observed. This document does not purport to address all of the safety problems associated with the product. It is the responsibility of the users of this document to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 1 Scope This document specifies the classification and designation, requirements and test methods, inspection rules, marking, packaging, transportation, storage, and safety of unused mineral and synthetic organic heat transfer fluids. This document is applicable to organic heat transfer fluids for various types of indirect heat transfer systems. This document is not applicable to organic heat transfer fluids directly used for heating or cooling chemicals with oxidizing properties. This document is not applicable to organic heat transfer fluids produced from reclaimed oils. Note: Products classified as L-QA according to GB/T 7631.12 are not suitable for organic heat transfer fluid boilers. This document is not applicable to products classified as L-QA according to GB/T 7631.12. 2 Normative references The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 259 Petroleum products - Determination of water soluble acids and alkalis GB/T 261 Determination of flash point - Pensky-Martens closed cup method GB/T 265 Petroleum products - Determination of kinematic viscosity and calculation of dynamic viscosity GB/T 268 Petroleum products - Determination of carbon residue - Conradson method GB/T 508 Petroleum products - Determination of ash GB/T 1884 Crude petroleum and liquid petroleum products - Laboratory determination of density - Hydrometer method GB/T 1885 Petroleum measurement tables GB/T 3078 Quality structural steel cold drawn bars GB/T 3535 Petroleum products - Determination of pour point GB/T 3536 Petroleum products - Determination of flash and fire points - Cleveland open cup method GB/T 4756 Method for manual sampling of petroleum liquids GB/T 4945 Standard test method for acid and base number of petroleum products and lubricants by colour-indicator titration GB/T 5096 Test method for corrosiveness to copper from petroleum products by copper strip test GB/T 6536 Standard test method for distillation of petroleum products at atmospheric pressure GB/T 7304 Standard test method for acid number of petroleum products by potentiometric titration GB/T 7534 Volatile organic liquids for industrial use--Determination of boiling range GB/T 7631.12 Lubricants, industrial oils and related products (class L) - Classification - Part 12: Family Q (Heat transfer fluids) GB/T 11133 Standard test method for determination of water in petroleum products, lubricating oils and additives - Coulometric Karl Fischer titration method GB/T 11140 Standard test method for sulfur in petroleum products by wavelength dispersive X-ray fluorescence spectrometry GB/T 16483 Safety data sheet for chemical products - Content and order of sections GB/T 17040 Determination of sulfur in petroleum and petroleum products - Energy dispersive X-ray fluorescence spectrometry GB/T 17144 Petroleum products - Determination of carbon residue - Micro method GB/T 21860 Liquid chemicals - Test method for the autoignition temperature GB/T 23800 Heat transfer fluids - Determination of thermal stability NB/SH/T 0164 Petroleum and related products packaging, storage, transportation and acceptance of delivery rules NB/SH/T 0558 Standard test method for boiling range distribution of petroleum fractions by gas chromatography NB/SH/T 0870 Standard test method for dynamic viscosity and density of liquids by Stabinger viscometer (and the calculation of kinematic viscosity) NB/SH/T 0956 Standard test method for kinematic viscosity of transparent and opaque liquids by automated houillon viscometer SH/T 0246 Determination of water content in light petroleum products (Coulometric method) SH/T 0604 Crude petroleum and petroleum products - Determination of density - Oscillating U-tube method SH/T 0689 Standard test method for determination of total sulfur in light hydrocarbons, motor fuels and oils by ultraviolet fluorescence TSG 11 Regulation on safety technology for boiler 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 organic heat transfer fluids general term for organic substances used as the heat transfer carrier Note 1: Organic heat transfer fluids include heat transfer fluids, hot oils, organic heat transfer carriers, heating media, and all other organic carriers used for indirect heat transfer purposes. Note 2: Based on chemical composition, organic heat transfer fluids can be classified into synthetic organic heat transfer fluids and mineral organic heat transfer fluids; based on boiling range, they can be classified into vapor phase organic heat transfer fluids and liquid phase organic heat transfer fluids. 3.2 unused organic heat transfer fluids organic heat transfer fluids that have not been injected into a heat transfer system for use Note: Products produced from reclaimed oils are excluded. 3.3 synthetic organic heat transfer fluids products produced by chemical synthesis processes, with specific chemical structures and definite chemical names Note: Based on the maximum permitted bulk temperature, synthetic organic heat transfer fluids are classified into ordinary synthetic type and those with special high thermal stability. 3.4 mineral organic heat transfer fluids products produced from appropriate fractions obtained through distillation and refining (including solvent refining and hydrorefining) processes using petroleum as raw material Note: The main components are hydrocarbon mixtures. 3.5 vapor phase organic heat transfer fluids synthetic organic heat transfer fluids with a boiling point or azeotropic point that can be used in the vapor phase Note: vapor phase organic heat transfer fluids can be used in the liquid phase by pressurization, also referred to as vapor phase/liquid phase organic heat transfer fluids. 3.6 liquid phase organic heat transfer fluids synthetic organic heat transfer fluids and mineral organic heat transfer fluids with a certain boiling range that can only be used in the liquid phase 3.7 thermal stability ability of organic heat transfer fluids to resist chemical decomposition at high temperatures Note: As the temperature increases, organic heat transfer fluids will undergo chemical reactions or molecular rearrangements, and the generated gaseous decomposition products, components with low boiling point, components with high boiling point, and nonvolatile decomposition products will affect the service performance of organic heat transfer fluids. 3.8 maximum permitted bulk temperature maximum test temperature at which the deterioration rate of the tested organic heat transfer fluid does not exceed 10% (mass fraction) as determined by the test specified in GB/T 23800 3.9 maximum working temperature

Contents Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Classification and designation 4.1 Product classification 4.2 Product designation 5 Requirements and test methods 6 Inspection rules 6.1 Inspection classification and items 6.2 Batching 6.3 Sampling 6.4 Judgment rules 6.5 Re-inspection rules 7 Marking, packaging, transportation and storage 8 Safety Annex A (Normative) Determination of total chlorine content in organic heat transfer fluids - Coulometric method A.1 Principle A.2 Apparatus A.3 Reagents and materials A.4 Test preparation A.5 Calibration A.6 Test procedures A.7 Calculation A.8 Precision Annex B (Normative) Test method for thermal oxidation stability of organic heat transfer fluids B.1 Principle B.2 Instruments and materials B.3 Reagents B.4 Preparation B.5 Instrument temperature calibration requirements B.6 Test procedures B.7 Calculation B.8 Precision B.9 Test report Annex C (Informative) Characteristics of organic heat transfer fluids C.1 General C.2 Properties C.3 Physical property parameters C.4 Safety data sheet