For a long time, roadway excavation has been mostly boring. This type of excavation method has many complicated and complicated processes, high labor intensity, low work efficiency and low speed of excavation. Therefore, researchers have been trying to replace the law with other methods for a long time, so there is a roadway boring machine.
In 1965 our country made the first of SJ-34 3.5m diameter tunnel boring machine type, then converted into a diameter of 5.3m of SJG53-12 type, before and after the 1970s, China's metallurgy, coal, iron road, water and electricity The national defense system has successively developed various types of roadheaders with a minimum diameter of 2.5m and a maximum of 6.8m, generally about 3m.
Coffee Grinder,Coffee Bean Grinder,Electric Coffee Grinder,Portable Coffee Grinder
Zhongshan Lianwei Electrical Technology Co., Ltd. , https://www.zslwwaterpump.com