GB/T 5686.7-2022 (English Version)

Standard No.: GB/T 5686.7-2022
Language: Chinese, English version preview
Release Date: 2022
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 5686.7-2022
Replace: GB/T 5686.7-2008

Scope: This document describes a method for the determination of sulfur in ferromanganese, manganese-silicon alloys, ferromanganese nitride and manganese metal by infrared absorption and combustion neutralization titration. This document is applicable to the determination of sulfur content in ferromanganese, manganese-silicon alloy, ferromanganese nitride and metallic manganese. Method 1 Determination range (mass fraction): 0.003%~0.120%; Method 2 Determination range (mass fraction): 0.015%~0.120%. Method 2 is not applicable to the determination of sulfur content in ferromanganese nitride.

Introduction

1. Background and significance of the standard

Ferromanganese, silicon manganese alloy, ferromanganese nitride and metallic manganese are important industrial materials, widely used in steel smelting and alloy production. Sulfur content, as a key indicator of these materials, directly affects their performance and application effects. The formulation of GB/T5686.7-2022 standard aims to unify the determination method and improve the accuracy of detection.

2. Comparative analysis of determination methods

Determination method	Scope of application	Sensitivity	Operation complexity
Infrared absorption method	Applicable to ferromanganese, manganese silicon alloy and ferromanganese nitride, with a determination range of 0.003%~0.120%	High sensitivity (up to 0.0001%)	Easy to operate and high degree of automation
Combustion neutralization titration method	Applicable to ferromanganese, manganese silicon alloy and metallic manganese, not applicable to ferromanganese nitride	Slightly less sensitive than infrared absorption method	Complicated operation, requires professionals

Application example: Determination of sulfur content in manganese silicon alloy

A steel plant used infrared absorption method to test manganese silicon alloy, and the result showed that its sulfur content was 0.015%, which met the industrial standard. Another enterprise used combustion neutralization titration method and measured the sulfur content of the same sample to be 0.016%, which was within the allowable range.

3. Background of standard formulation and technological evolution

The GB/T5686 series of standards originated in 1988. This revision mainly optimized the accuracy and scope of application of the determination method. Technical improvements include:

Introduction of highly sensitive instruments (such as high-frequency infrared carbon and sulfur analyzers)
Increase blank value requirements for calibration tests
Optimization of the analysis result acceptance procedure

4. Implementation recommendations and precautions

To ensure the accuracy of the measurement, it is recommended to:

Choose instruments that meet the accuracy requirements (such as high-frequency infrared carbon and sulfur analyzers)
Strictly control blank tests and standard material calibration
Operators need to receive professional training

For different materials, the appropriate method should be selected according to their characteristics. For example, ferromanganese nitride is only suitable for infrared absorption method.

GB/T 5686.7-2022 Referenced Document

GB/T 4010 Ferroallys sampling and preparation of samples for chemical analysis
GB/T 6379.1 Accuracy(trueness and precision)of measurement methods and results Part 1:General principles and definitions
GB/T 6379.2 Accuracy(trueness and precision)of measurement methods and results-Part 2:Basic method for the determination of repeatability and reproducibility of a standard measurement method
GB/T 6682 Water for analytical laboratory use.Specification and test methods
GB/T 8170 Rules of rounding off for numerical values & expression and judgement of limiting values

GB/T 5686.7-2022 history

2022 GB/T 5686.7-2022 Ferromanganese，ferromanganese-silicon，nitrogen-bearing ferromanganese and manganese metal—Determination of sulfur content—Infrared absorption method and combustion-neutralization method
2008 GB/T 5686.7-2008 Ferromanganese, ferromanganese-silicon, nitrogen-bearing ferromanganese and manganese metal. Determination of sulfur content. Infrared absorption method and combustion-neutralization method
1988 GB/T 5686.7-1988 Methods for chemical analysis of silicomanganese alloy--The infrared absorption method for the determination of sulfur content

GB/T 5686.7-2022