不卡视频一区二区三区,婷婷成人av,国产精品一区视频,久久夜色精品国产噜噜av小说,国产精品性夜天天视频,亚洲日产永久经典,九九国产精品入口麻豆

Xingtai Steel 35VB belongs to the high strength alloy structural steel, with the advantages ofstable composition, low harmful element, high steel purity, small decarburization layer, less surface defects, etc.While it has high strength, high impact toughness, high fatigue strength and high strength of the gap and good Cutting and welding. It is usually used in hot rolled annealed conditions, for producing high strength of connecting rod, bolts, etc.