GB/T 16555-2025Chemical analysis of refractories containing carbon, silicon carbide or nitride (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part

1.Structure and Drafting Rules of Standardization Documents". Drafting. This document replaces GB/T 16555-2017 "Chemical Analysis Methods for Carbon-Containing, Silicon Carbide, and Nitride Refractory Materials", and is consistent with GB/T 16555- Compared to.2017, aside from structural adjustments and editorial changes, the main technical changes are as follows:

a) An electric furnace and a pH meter were added (see 4.5, 4.12);

b) The regulations for pure water have been changed (see 6.1.1, see

6.1.1 in the.2017 version);

c) The holding time for determining the loss on ignition at 850°C using the box furnace oxidation method was modified, and the determination of loss on ignition at 1050°C was added. Method (see 8.2);

d) The reaction equation was modified (see 14.1.1,

15.1.1 in the.2017 version);

e) Added specifications for the volume of gas measuring tubes and reference tubes (see 14.1.2.10);

f) The determination of hafnium oxide and yttrium oxide has been added (see Chapter 17);

g) The analysis items and test personnel in the test report have been added (see Chapter 18). Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents. This document was proposed and is under the jurisdiction of the National Technical Committee on Standardization of Refractory Materials (SAC/TC193). This document was drafted by: China Steel Group Luoyang Refractory Materials Research Institute Co., Ltd., and Shanghai Xintaishan High Temperature Engineering Materials Co., Ltd. Yixing Refractory Materials Co., Ltd., Luoyang Lier Functional Materials Co., Ltd., and Changxing Xingying New Refractory Building Materials Co., Ltd. The main drafters of this document are. Xu Xiaoying, Cao Haijie, Lei Xiaoyu, Li Hongbo, Yuan Biao, Zhao Wei, Xu Gao, Ao Ping, Li Yongwei, Sun Xudong, and Yan Hao. Wang Qiang, Wang Xiaoli, Ma Sikai, Liu Lei. The document replaced by this document has been released in the following versions.

---First published in.1996 as GB/T 16555.1~16555.6-1996;

---First revision in.2008, amending GB/T 16555.1~16555.6-1996, GB/T 13245-1991 and GB/T 13246- Content merged in.1991;

---The second revision in.2017 resulted in GB/T 16555-2017, "Chemical Analysis of Carbon-Containing, Silicon Carbide- and Nitride-Containing Refractory Materials". method";

1 Scope

GB/T 16555-2025 is the Chinese national standard on chemical analysis of refractories containing carbon, silicon carbide or nitride, in the field of glass and ceramics industries. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 29 August 2025 by the State Administration for Market Regulation; Standardization Administration of China, and has been in force since 1 March 2026. Classification: ICS 81.080, CCS Q40. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This document describes the heat treatment loss on ignition, volatile matter, total carbon content, free carbon content, and carbon content of carbon-containing, silicon carbide, and nitride refractories. Chemical content of silicon nitride, total nitrogen, total oxygen, silicon nitride, free silicon, free aluminum, iron oxide, aluminum oxide, and other oxides Analytical methods. This document applies to carbon-, silicon carbide-, and silicon nitride-containing refractory materials, such as magnesia-carbon bricks, semi-graphite carbon bricks, alumina-zirconium-carbon bricks, and silicon carbide-containing castables. Chemical analysis of silicon nitride-bonded silicon carbide bricks, etc.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included. For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies. This document.

GB/T 223.69-2008 Determination of Carbon Content in Iron and Steel and Alloys - Volumetric Method of Gas After Combustion in Tubular Furnace

GB/T 4513.2 Unshaped refractories - Part

3 Terms and Definitions

The terms and definitions defined in GB/T 18930 apply to this document.

5 Sample Preparation

5.1 Sampling Laboratory samples shall be drawn in accordance with GB/T 10325, GB/T 17617 or GB/T 4513.2.