Device development and experimental study on the methane explosion ignited by sparks of cable bolt slippage (breakage)

Abstract

The first experimental device in the world was designed for studying methane explosion ignited by sparks of cable bolt slippage (breakage), which was designed with the same size as underground and the length of cable bolt can be tested as long as 7.0 m. It can also carry out shock loading and preload of cable bolt which represent underground cable bolt slippage (breakage). The system pressure and impact velocity of the device is adjustable, also can conduct a series of experiments under methane environment. A series of experiments were conducted to study the possibility of spark generation during Ф15.24×6500 mm cable bolt slippage (breakage) and the probability of methane explosion caused by the spark. The results show that, when the exposed length of cable bolt is less than 200 mm, the maximum temperature of the spark generated by cable bolt slippage (breakage) is far less than the required ignition temperature for a methane explosion of 650℃ , and the duration of spark is less than 0.12 second, The spark generated by the slippage (breakage) of cable bolt couldn't ignite a methane explosion.