Compared with the dry spraying, the wet spraying process of the mine wet shotcrete machine has added a quick setting agent addition system and a feeding and stirring system in addition to the spraying system, and the volume and weight of the mine wet shotcrete machine have increased. The underground coal mine has a small cross section, is paved with tracks, and is also equipped with other equipment, which is very inconvenient to work. This is a problem that needs to be solved in the promotion and use of the mine wet shotcrete machine. There are many problems that need to be solved in the promotion and application of the mine wet shotcrete machine.
The mine dry shotcrete machine needs to be connected with the spraying pipeline, gas circuit, circuit, and water circuit, while the mine wet shotcrete machine needs another circuit and quick-setting agent pipeline. The weight of dry shotcrete machine for mining is about 600 kg, and the weight of wet shotcrete machine for mining is 1500 kg. The workload of transferring wet shotcrete machine for mine is obviously larger. After the spraying, the dry shotcrete machine for mine only needs to be cleaned with wind. The wet shotcrete machine for mine must be cleaned with water; the residual concrete and accelerating agent in the machine must be added to the speed in the system. The coagulant is flushed with water, otherwise the machine will be unusable the next time. The mine dry shotcrete machine is to use the mine truck and other equipment to send the dry mixed concrete to the working face, and manually feed the concrete shotcrete machine to spray the slurry.
After the introduction of the mine wet shotcrete machine, the traditional concrete mixing and transportation technology can no longer meet the requirements. The underground project has the characteristics of small demand for concrete in a single operation, wide working points and constantly changing construction sites, which requires long-distance transportation. Therefore, solving the long-distance transportation has become the key to the popularization and application of mining wet shotcrete machine. There are two ways of conveying concrete by the mine wet shotcrete machine. One is to use compressed air to form a thin dilute flow in the conveying pipeline. The conveying distance is up to 30 meters. Many coal mines require more than 30 meters. The other is to use pumping to form dense and dense flow transmission in the transmission pipeline, the transmission distance is long, but it needs to be connected to the steel pipe for a long distance, and finally connected with the spray pipe, the operation is complicated. After the spraying is completed, the residual concrete needs to be cleared out with water, so the requirements for conveying materials are more strict, and once the pipe is blocked, safety accidents are easy to occur.
Because the structure of mine wet shotcrete machine is more complicated than that of dry shotcrete machine, the difficulty of maintenance is higher than that of dry shotcrete machine. In addition, when the workers operate the mine wet shotcrete machine, improper use may cause personal injury. Because the coal mine chamber is small, the pungent odor generated by the liquid accelerator cannot be emitted. The liquid accelerator is strongly alkaline and splashes. If you touch it, it will cause personal injury. China Coal Group will do its utmost to improve the innovation and promotion of mining wet shotcrete machine, we will actively promote the difficulties encountered in the actual construction of mining wet shotcrete machine!
