久久综合九色综合97婷婷-亚洲熟妇天堂一区二区三区-国产高清不卡在线观看-可以在线观看的亚洲视频

The role of light has the four aspects:
1, the pressing strip surface, make the zinc layer better stick to the strip surface;
2, control panel, improve product quality;
3, improve the strip steel mechanical properties, eliminate the yield platform;
4, roughness, make it easier for steel strip after finishing antirust processing.