GB/T 41633.3-2022Insulating liquids - Determination of acidity - Part 3: Test methods for non-mineral insulating oils (English PDF)

Foreword

This document was issued on 8 November 2022 by the State Administration for Market Regulation; Standardization Administration of the PRC and takes effect on 1 June 2023.

It is a GB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

It is classified under ICS 29.040.10, Chinese classification K15.

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1.Structure and Drafting Rules for Standardization Documents"

drafting.

This document is part 3 of GB/T 41633 "Determination of Acid Value of Insulating Liquids". GB/T 41633 has issued the following parts.

--- Part 2.Colorimetric titration;

--- Part 3.Test methods for non-mineral insulating oils.

This document is identical to IEC 62021-3.2014 "Determination of Acid Value of Insulating Liquids Part 3.Test Method for Non-Mineral Insulating Oils"

Law".

Please note that some contents of this document may refer to patents. The issuing agency of this document assumes no responsibility for identifying patents.

This document is proposed by China Electrical Equipment Industry Association.

This document is under the jurisdiction of the National Standardization Technical Committee of Insulation Materials (SAC/TC51).

This document was drafted by. State Grid Henan Electric Power Company Electric Power Research Institute, Guilin Saimeng Testing Technology Co., Ltd., State Grid Zhejiang Province

Electric Power Research Institute of Electric Power Company, Shenzhen Jinghao Capacitor Co., Ltd., Guilin Electrical Appliance Science Research Institute Co., Ltd., Guangdong Power Grid Co., Ltd.

Ren company Electric Power Research Institute, Guangdong Yisheng Testing Co., Ltd., Zhejiang Huiri Environmental Testing Co., Ltd., Zaozhuang Huitian Meiya Insulation Festival

Energy Building Materials Co., Ltd., Xi'an Kaijinzhe Testing Co., Ltd., Dongguan Ruijing Electric Technology Co., Ltd., Guangdong Tehua Technology Co., Ltd., Guangdong

Chengxin Technology Co., Ltd., Zhejiang Anya Intelligent Technology Co., Ltd., Shaanxi Runzheng Testing Technology Co., Ltd., Guangdong Yidu Technology Co., Ltd.,

Yiwu Quanyi Mold Industry Development Co., Ltd., Shaanxi Jinyoubang Technology Co., Ltd., Jiangsu Meixida Technology Co., Ltd.

The main drafters of this document. Kou Xiaoshi, Yang Tao, Shao Xianjun, Zhao Jie, Liao Zhifei, He Yuping, Li Chen, Wu Zhuoting, Xiong Xuemei, Luo Chuanyong,

Qian Yihua, Fu Qiang, Xiang Xiaoyun, Wang Cuilin, Song Guangsheng, Wu Caichun, Lin Jinli, Zhang Yuanlin, Huang Jianwei, Nan Shaowei, Deng Daicong, Li Shouying,

Jin Chenggao, Su Shiqiao, Pi Kunlan.

Introduction

health and safety

This document is not intended to address all safety issues related to its use, and it is the user's responsibility to establish appropriate health

and safety rules to ensure the applicability of this document.

The mineral oil involved in this document should be protected by personal protection. If it comes into direct contact with the eyes, it may cause slight pain. If it comes into contact with the eyes, use

Flush eyes with plenty of clean running water and seek medical attention.

Some of the tests covered in this document may result in hazardous conditions. Please refer to the relevant guidance documents.

environment

This document will refer to mineral oil, chemicals and used sample containers. Relevant disposal should avoid impact on the environment, and various measures should be taken.

This preventive measure prevents minerals from polluting the environment.

The acid value measurement standard of insulating liquid is widely used in the research and development, production, quality inspection, sales, acceptance and technical exchange of insulating liquid products.

This series of standards can guide the industry to more effectively carry out the detection and evaluation of the acid value of insulating liquids, and can improve the quality and quality of insulating liquid products.

Application reliability.

The standards for the determination of the acid value of insulating liquids are written in different parts. In order to maintain the same writing method as the corresponding IEC standards,

When compiling this series of documents, different parts need to be compiled separately.

GB/T 41633 describes the standard method for the determination of the acid value of insulating liquids, which is proposed to consist of the following parts.

--- Part 1.Automatic potentiometric titration. The purpose is to determine the method and procedure for measuring the acid value of insulating liquid by automatic potentiometric titration.

--- Part 2.Colorimetric titration. The purpose is to determine the method and procedure for measuring the acid value of insulating liquid by colorimetric titration.

--- Part 3.Test methods for non-mineral insulating oils. The purpose is to identify unused and used non-mineral insulating oleic acid for electrical purposes

There are two test methods for the value. automatic potentiometric titration and colorimetric titration.

Determination of acid value of insulating liquid

Part 3.Test methods for non-mineral insulating oils

1 Scope

GB/T 41633.3-2022 is the part of the GB/T 41633 series that covers the measurement of acidity in unused and used non-mineral insulating oils for electrical purposes, setting out two routes to the same figure. Method A is automatic potentiometric titration, taken from its principle through the reagents and auxiliary materials, the instrument, the sampling, the preparation and maintenance of the electrode, the calibration, the titration steps, the calculation of the result, the precision and the report. Method B is colorimetric titration, with its own principle, reagents, instruments, sampling, procedure, calculation, precision and report, for laboratories working without an automatic titrator. An informative annex adds determination by photometric titration. Acidity is what oxidation leaves behind: organic acids, phenolic compounds and other oxidation products accumulate as a fluid ages in service, attack the cellulose insulation and the metal parts around it, and give early notice that a charge of fluid is reaching the end of its useful life. Esters and other non-mineral fluids do not behave like mineral oil in a titration cell, so the electrode conditioning and the end-point judgement carried over from mineral-oil practice can drift or settle on a false end point. Written for insulating fluid laboratories, utility condition-monitoring teams, and the producers and reclaimers of non-mineral fluids.

This document describes two test methods for the acid value of unused and used non-mineral insulating oils for electrical purposes. potentiometric titration and colorimetry

titration.

Note 1.In unused and used electrical non-mineral insulating oils, acidic components include organic acids, phenolic compounds, oxidation products, resins, organic gold

Salt and additives etc.

This document may be used to indicate the relative change that occurs during service of non-mineral insulating oils for electrical purposes under oxidizing conditions, regardless of their color

Whether the degree or other characteristics have changed.

Acid value can be used for quality control of unused non-mineral insulating oils for electrical purposes. Oxygen present in used electrical non-mineral insulating oils

Oxidation products will affect its acid value, and these oxidation products have large differences in corrosion characteristics, so this document cannot be used to predict

Corrosiveness of electrical non-mineral insulating oils in use.

Note 2.The acid value results measured by potentiometric titration and the acid value results measured by colorimetric titration may be the same or different in value, but they are usually

are in the same order of magnitude.

2 Normative references

The contents of the following documents constitute the essential provisions of this document through normative references in the text. Among them, dated references

For documents, only the version corresponding to the date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to

this document.

Note. GB/T 6379 (all parts) Accuracy (trueness and precision) of measurement methods and results [ISO 5725 (all parts)]

Note. GB/T 41146-2021 insulating liquid sampling method (IEC 60475.2011, IDT)

3 Terms and Definitions

The following terms and definitions apply to this document.

3.1

acidity

After the sample is dissolved in the specified solvent by potentiometric titration or colorimetric titration, the amount of alkali required for titration to the end point is calculated as the sample

expressed as the mass fraction of potassium hydroxide.

Note. See Appendix A for the determination of the acid value of non-mineral insulating oil by photometric titration.