GB/T 15344-2020 in English

Core changes in the standard revision

Analysis of Key Detection Methods

4.1 Comparison of Two Methods for Moisture Determination

The standard provides two methods: oven method (Method A) and moisture meter method (Method B):

• Oven method: Dry at 105-110℃ for 1.5-2h, and weigh repeatedly until constant weight
• Instrument method: Direct measurement using moisture meter, completed within 25min, temperature control accuracy ±0.5℃

The allowable difference of parallel tests is controlled according to the moisture content, with the minimum requirement of ≤0.1% (when X_i≤0.5%)

4.9 Technological innovation of laser particle size method

The new standard adopts the laser particle size analyzer specified in GB/T 19077:

1. Pretreatment: ultrasonic dispersion + sodium hexametaphosphate solution (2g/L)
2. The measurement range covers fine (0.1μm) to ultrafine (1000μm) particles
3. Compared with the traditional sedimentation method, the efficiency is improved by 80%, avoiding human errors

Implementation and application suggestions

Background of standard evolution

This standard is under the jurisdiction of the National Non-metallic Mineral Products Standardization Committee (SAC/TC406). The main technical changes reflect:

• Modernization of detection technology: 6 methods quote GB/T 8170 data rounding rules
• Response to industry needs: Added firing whiteness index to meet the requirements of the ceramic industry
• International integration: Adopt ISO 13320 Particle size analysis based on laser diffraction principle