av永久免费观看,日韩在线精品视频,在线观看国产视频,国产精品久久片,国产毛片av网站,国产又粗又硬又黄又刺激,国产黄色片视频

Casus Products>> Casus

  The Q10B21 produced by XINGTAI STEEL has stable composition, low harmful elements, small decarburization layer, few surface defects, and excellent hardenability. it can directly reduce production costs because of its non annealing processing. A customer of XINGTAI STEEL used this steel grade to produce 8.8 grade bolts. The customer reported that the product has stable drawing performance, no cracking during cold heading, and stable performance after heat treatment.