MT/T 962-2019 in English

Background of Standard Revision and Technological Evolution

MT/T 962-2019 replaces the 2005 version of the standard and systematically upgrades the roller coating technology for belt conveyors in underground coal mines. The main technical evolution includes:

Analysis of key technical requirements

4.1 Appearance quality

New standard for class=instrument>Ceramic rubber composite coating layer increases the requirements for uniform distribution of ceramic tiles:
- Corner notch depth ≤2mm and ≤1 for each tile
- Ceramic tile position offset ≤1.5mm and ≤6 tiles for each tile

4.2 Physical and mechanical properties

Innovative technical requirements

4.3 Ceramic sheet performance

The core indicators of the ceramic composite layer are specified for the first time:
- Wear volume ≤0.06cm³ (GB/T 27979)
- Rockwell hardness ≥82HRA
- Compressive strength ≥850MPa

4.5 Bonding strength

The new requirement of bonding strength ≥4.0MPa of ceramic-rubber interface is added to solve the problem of traditional composite layer peeling.

Upgraded safety performance

4.6 Flame retardant performance

Dual standard test:
- Alcohol lamp burning: Flameless burning ≤60 seconds
- Blowtorch burning: Flame burning ≤10 seconds

4.7 Electrical conductivity

Surface resistance ≤3×10⁸Ω (MT 113 test method), exempt when the bonding surface thickness ≤1.5mm.

Implementation suggestions

Production process control

1. The ceramic composite layer should adopt the pre-vulcanization + hot pressing process
2. The polyurethane pouring temperature is controlled at 110±5℃
3. The surface of the metal drum needs to be sandblasted (Sa2.5 grade)

Key points of quality inspection

- Random inspection for every 2000kg batch
- Peel strength test pieces need to be cured for 72 hours before testing
- Type inspection requires 5kg sample + metal substrate