At the construction site of Metro Line 4 in Chang'an District, Shijiazhuang, four Xieyan Machinery 90-type concrete spraying wet spraying machines performed brilliantly. They are equipped with an efficient concrete mixing and conveying system, which can quickly and evenly spray concrete onto the inner wall of the tunnel. Under complex geological conditions, the equipment operates accurately and greatly improves construction efficiency. Compared with traditional construction methods, Xieyan Machinery's concrete spraying equipment not only speeds up the progress, but also reduces material waste, which has effectively promoted the construction progress of Metro Line 4 and helped Shijiazhuang's transportation network to continue to improve.